low-energy building design guidelines

Internet: http://www.eren.doe.gov/femp/

IntroductionIncorporating energy efficiency, renewable energy,and sustainable green design features into allFederal buildings has become a top priority inrecent years for facilities managers, designers, contracting officers, and others in governmentbuildings procurement. These progressive designstrategies have been formalized through ExecutiveOrder 13123 (known as Greening the Governmentthrough Efficient Energy Management), which wasissued on June 3, 1999. There are significant oppor-tunities to accomplish the goals set forth in the executive order, whether in new building design or in the context of renovations. This guidebookaddresses the first category—the design process for new Federal facilities. Because energy-efficientbuildings reduce both resource depletion and theadverse environmental impacts of pollution gener-ated by energy production, it is often considered to be the cornerstone of sustainable design. In thispublication, we will be looking at what low-energydesign means, specific strategies to be considered,when and where to apply these strategies, and howto evaluate their cost effectiveness.

Low-energy building design is not just the result ofapplying one or more isolated technologies. Rather,it is an integrated whole-building process thatrequires advocacy and action on the part of thedesign team throughout the entire project devel-opment process. The whole-building approach is easily worth the time and effort, as it can save 30%or more in energy costs over a conventional build-ing designed in accordance with Federal Standard10 CFR 435. Moreover, low-energy design does notnecessarily have to result in increased constructioncosts. Indeed, one of the key approaches to low-energy design is to invest in the building’s form andenclosure (e.g., windows, walls) so that the heating,cooling, and lighting loads are reduced, and in turn,smaller, less costly heating, ventilating, and air conditioning systems are needed.

In designing low-energy buildings, it is important toappreciate that the underlying purpose of the build-ing is neither to save—nor use—energy. Rather, thebuilding is there to serve the occupants and their

activities. An understanding of building occu-pancy and activities can lead to buildingdesigns that not only save energy and reducecosts, but also improve occupant comfort andworkplace performance. As such, low-energy build-ing design is a vital component of sustainable, greendesign that also helps Federal property managersmeet the requirements of the Energy Policy Act of1992, Executive Order 13123, and other climatechange goals.

The low-energy design process begins when theoccupants’ needs are assessed and a project budget is established. The proposed building is carefullysited and its programmed spaces are carefullyarranged to reduce energy use for heating, cooling,and lighting. Its heating and cooling loads are mini-mized by designing standard building elements—windows, walls, and roofs—so that they control,collect, and store the sun’s energy to optimumadvantage. These passive solar design strategiesalso require that particular attention be paid tobuilding orientation and glazing. Taken together,they form the basis of integrated, whole-buildingdesign. Rounding out the whole-building picture is the efficient use of mechanical systems, equip-ment, and controls. Finally, by incorporating build-ing-integrated photovoltaics into the facility, someconventional building envelope materials can bereplaced by energy-producing technologies. Forexample, photovoltaics can be integrated into window, wall, or roof assemblies, and spandrelglass, skylights, and roof become both part of thebuilding skin and a source of power generation.

This guidebook has been prepared primarily forFederal energy managers to provide practical infor-mation for applying the principles of low-energy,whole-building design in new Federal buildings. An important objective of this guidebook is to teachenergy managers how to be advocates for renewableenergy and energy-efficient technologies, and howto apply specific strategies during each phase of agiven project’s time line. These key action items arebroken out by phase and appear in abbreviatedform in this guidebook.

Low-Energy Building Design GuidelinesEnergy-efficient design for new Federal facilities

F E D E R A L E N E R G Y M A N A G E M E N T P R O G R A M

A guidebook of practicalinformation on design-ing energy-efficientFederal buildings.

Prepared by the New Technology Demonstration Program

No portion of this publi-cation may be altered inany form without priorwritten consent from the U.S. Department ofEnergy and the author-ing national laboratory.

DOE/EE-0249


Disclaimer

This report was sponsored by the United States Department of Energy, Office of Federal Energy ManagementPrograms. Neither the United States Government, nor any agency or contractor thereof, nor any of their employees,makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, complete-ness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use wouldnot infringe privately owned rights. Reference herein to any specific commercial product, process, or service by tradename, mark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommenda-tion, or favoring by the United States Government or any agency or contractor thereof. The views and opinions of theauthors expressed herein do not necessarily state or reflect those of the United States Government or any agency orcontractor thereof.


ContentsIntroduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1

About the Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5

Application Domain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Energy-Saving Mechanisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Advantages of Low-Energy Building Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Applications Screening . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Building Types: Characteristics and Profiles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Integrating Low-Energy Concepts into the Design Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12

What to Avoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

Design Considerations and Computer Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

Strategy Interactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

The Benefits of Multiple Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30

Design and Analysis Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

Energy Savings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

Other Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

Case Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

The Technology in Perspective . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Technology Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Technology Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Product Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

Who is Using the Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

For Further Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Appendix A: Climate and Utility Data Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42

Appendix B: Federal Life-Cycle Costing Procedures and the Building Life Cycle Cost (BLCC) Software . . . . . . . . . .42

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About the TechnologyBuildings consume roughly 37% of theprimary energy and 67% of the totalelectricity used each year in the UnitedStates. They also produce 35% of U.S.and 9% of global carbon dioxide (CO2)emissions. Preliminary figures indicatethat in FY 1997, Federal governmentfacilities used nearly 350.3 trillion British thermal units (Btus) of energy in approximately 500,000 buildings at a total cost of $3.6 billion.

By following a careful design process, itis possible to produce buildings that usesubstantially less energy without com-promising occupant comfort or thebuilding’s functionality. Whole-buildingdesign considers the energy-relatedimpacts and interactions of all buildingcomponents, including the building site; its envelope (walls, windows,doors, and roof); its heating, ventilation,and air-conditioning (HVAC) system;and its lighting, controls, and equip-ment. This stands in marked contrast to the traditional design process, wherethere is generally no goal to minimizeenergy use and costs beyond what isrequired by codes and regulations.

Executive Order 13123 calls for a 30%reduction in energy use per gross squarefoot by 2005. To achieve this goal, theagency and design team must establishminimized energy use as a high prioritygoal at the inception of the design process.A balanced and appropriately fundedteam must be assembled that will workclosely together, maintain open lines ofcommunication, and remain responsiveto key action items throughout the delivery of the project.

Continuing advocacy of low-energydesign strategies is essential to realizingthe goal. Therefore, it is important that at least one technically astute member of the design team be designated as theenergy advocate. This team member performs many useful functions, such as:

• Introducing team members to designstrategies that are appropriate to build-ing type, size, and location.

• Maintaining enthusiasm for the inte-gration of low-energy design strategiesas central components of the overalldesign solution.

• Ensuring that these strategies are notabandoned or eliminated during thelater phases.

• Overseeing construction to ensure thatthe strategies are not thwarted or com-promised by field changes.

For most projects, it is also highly advis-able to retain an experienced low-energydesign consultant. Because low-energydesign is not entirely intuitive, experi-ence gained from a range of projects isvital. Indeed, the energy use and energycost of a building depend on the com-plex interaction of many parameters and variables that require detailedanalysis on a project-by-project basis.Some of the attributes that an energyconsultant should bring to the projectinclude:

• Sufficient background to identifypotential strategies based on experience.

• Knowledge of Federal informationsources (e.g., Federal Energy Manage-ment Program, national laboratories),

Federal requirements (e.g., 10 CFR 435and 436 Energy Star™ buildings andequipment, energy-savings perform-ance contracting), the Energy Policy Act of 1992 (EPAct), and other relevantexecutive orders.

• Technical expertise that generatesenthusiasm, cooperation, and respectamong team members.

• The capacity to efficiently use detailedcomputerized energy simulation pro-grams such as the latest version ofEnergy 10 or DOE 2.

• The ability to make informed designrecommendations based on computerresults and life-cycle economic analyses.

• A breadth of experience sufficient toconsider design options that not onlysave energy, but are also integrated withother project needs, including aestheticconsiderations.

In sum, the energy consultant shouldserve as a catalyst for eliciting innova-tive energy-conserving design ideasfrom the entire design team. In somecases, other members of the project team (such as the design architect andengineer) may, themselves, be quite pro-

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Estimated Costs for Low-Energy Design Consulting Services

Investment ($/ft2)

Small buildings Medium buildings Large buildings Energy Use Type (0 to 20,000 ft2) (20,000 to 100,000 ft2) (100,000 ft2 and above)

Moderate Energy UsersIncluding single family residences, housing,and warehouses $0.35 to $0.25 $0.25 to $0.15 $0.15 to $0.05

High Energy UsersIncluding offices, factories, and service centers $0.40 to $0.30 $0.30 to $0.20 $0.20 to $0.10

Very High Energy UsersIncluding laboratories and hospitals $0.45 to $0.35 $0.35 to $0.25 $0.25 to $0.15

Note:This table adjusts the rule of thumb for building size and energy use characteristics andprovides a more precise guideline. Note that as buildings get larger, there is an economy ofscale, so it is not necessary to expend as much on a square-foot basis.

U.S. Department of Energy (DOE) Federal Energy Management Program (FEMP), March 1999.Procuring Low-Energy Design and Consulting Services: A Guide for Federal Managers, Architects, andEngineers, available at www.nrel.gov or www.eren.doe.gov/femp.


ficient in low-energy building designand will respond well to the challenge.

The only thing that may hold them backfrom advocating low-energy design onany particular project is the lack of a com-mitment and appropriate funding by theowner or agency. Estimated costs for thisconsulting service can be obtained fromthe table on the previous page.

Application DomainThe application domain for low-energydesign is not so much a case of wherethe technology should be installed, butwhere it is integrated with the other elements of the project to produce anenergy-efficient building that servesboth the environmental and functionalneeds of its users. When thinking aboutwhole buildings, it is important to con-sider not only the discrete componentsand materials but how the various partscan best work together to achieve thedesired results. That is what is meant bythe phrase “integrated, whole-buildingdesign.” Low-energy design strategiesand renewable energy concepts can beapplied to almost any type of newFederal building.

Energy-Saving MechanismsIn Federal buildings, low-energy designmechanisms range from a few high-pro-file architectural features that are solarresponsive to the application of moreconventional, and often less conspicu-ous, energy conservation technologies.Many applications are reconfigurationsof typical building components, such asa change from flat façades and roofs tothose that are articulated and have sur-faces designed to bounce or block directsolar rays.

The low-energy design process describedin this guidebook combines a broad rangeof practical systems, devices, materials,and design concepts that should be con-sidered simultaneously whenever possi-ble to achieve significant reductions inenergy use. For most non-residentialbuildings, an energy-use reduction of30% below what is required by codesand standards can usually be achievedwith little, if any, increase in construc-

tion cost. The figure is closer to a 50%reduction in residences. Savings of 70%or more are possible for exemplary build-ings, although achieving such significantreductions can be challenging in light ofthe demands occasioned by budgetingconstraints and cost-effectiveness crite-ria. For example, daylighting, coupledwith dimmable lighting and light-levelcontrols, is increasingly commonplace.An effective and highly recommendedenergy conservation strategy, this tech-nology cluster is an important compo-nent of low-energy building design. (See Applications Screening and How to Apply)

Because energy-efficiency concepts andtechnologies must dovetail with all otherbuilding elements, one of the mostimportant energy-saving tools is the use of computer modeling and designsoftware. This strategy should be usedearly in the design process to analyze the efficiency and cost effectiveness ofcandidate strategies. Detailed computersimulation results are then referred tothroughout the design process, and often through the value engineering(VE) phase, to ensure that the buildingwill efficiently perform as intended, andthat subsequent changes to the design in the interest of cost-cutting do notadversely affect performance. By usingappropriate energy simulation tools inthe context of a whole-buildingapproach that emphasizes solar tech-nologies and energy efficiency, designteams can achieve significant operatingcost savings while still staying on bud-get. A list of design and analysis tools isprovided later.

Advantages of Low-Energy BuildingDesign While basic techniques and concepts areimportant, of greater relevance to a givenbuilding project are the specific low-energy building design techniquesthemselves. One key element of low-energy building design is the inventiveuse of the basic form and enclosure of abuilding to save energy while enhancingoccupant comfort. The section titled Howto Apply describes a wide range of low-energy building design strategies thatcan be commonly applied to new Federalbuildings. Low-energy building designcombines energy-conservation strategiesand energy-efficient technologies. Someof these are described in FEMP FederalTechnology Alerts (FTAs), includinghigh-efficiency lighting and lightingcontrols, spectrally selective glazing,and geothermal heat pumps.

Low-energy design represents both aload-reduction strategy and the incor-poration of renewable energy sources.Many low-energy building design strat-egies result in an absolute reduction inthe use of power produced from fossilfuels. Together these innovations cansave energy, reduce costs, and preservenatural resources while reducing envi-ronmental pollution. Low-energy build-ing design strategies (including variousdaylighting techniques) can also providea renewed sense of connection with theoutdoors for occupants of Federal facili-ties. Low-energy design can also inspireplanning concepts, such as interior pri-vate offices that borrow light from openoffice spaces at the building’s perimeter.

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Basic energy-saving techniques should be used to reduce building energy use.

• Siting and organizing the building configuration and massing to reduce loads.

• Reducing cooling loads by eliminating undesirable solar heat gain.

• Reducing heating loads by using desirable solar heat gain.

• Using natural light as a substitute for (or complement to) electrical lighting.

• Using natural ventilation whenever possible.

• Using more efficient heating and cooling equipment to satisfy reduced loads.

• Using computerized building control systems.


More difficult to measure are the increasesin workplace performance and produc-tivity that are often achieved throughwhole-building design and its resultingeconomic value. Nonetheless, organiza-tions housed in low-energy buildingshave reported that their indoor environ-ments help retain employees, reducetension, promote health, encourage communication, reduce absenteeism,and, in general, improve the work envi-ronment. Another potentially significantbenefit is the public perception that, byits own example, the Federal govern-ment is helping to lead the constructionindustry toward a more responsible andsustainable future. Similarly, by usingpublic funds for cost-effective measuresthat reduce operating costs, Federalagencies are performing these tasks in a responsible and frugal manner.

ApplicationLow-energy building design techniquesare application specific. This section provides a practical method of deter-mining the potential use of design tech-niques in different types of Federalbuildings, in different climatic locations,and under various local energy cost scenarios. It also details the process and level of advocacy required to assuresuch strategies are considered and incor-porated into the design process, begin-ning with the earliest project phases (see Needs Assessment and Site Selec-tion) and continue through Construc-tion and Building Occupancy. Refer tothe time line on pages 22–23 for an illustration of the various phases andkey action items to be addressedthroughout the process.

For a particular project, the specific ener-gy-saving techniques, strategies, andmechanisms to be deployed will varygreatly, depending on building andspace type. Their selection and configu-ration will also be influenced by:

• Climate

• Internal heat gains from occupants andtheir activities, lights, and electricalequipment

• Building size and massing

• Illumination (lighting) requirements

• Hours of operation

• Costs for electricity and other energysources.

In reviewing this list, one can quicklygrasp that strategies specific to a partic-ular building or space may not worknearly as well (or at all) in another appli-cation. Therefore, some general guid-ance about building and space types(provided in Applications Screening)will prove useful in understanding thefactors that lead to significant energy usein buildings and in identifying the strat-egies that can yield optimum savings.

It is essential that the team appreciate thata successful design solution under oneset of circumstances may not be appro-priate or cost effective for a differentbuilding type, size, or configuration; thesame building type constructed in a dif-ferent climate; or where variable energycosts apply.

Applications ScreeningThe use characteristics discussed beloware representative of the majority ofFederal building projects. The first steptoward assuring low-energy buildingdesign for a particular project is tounderstand the energy implications ofthe structure’s basic form, organization,and internal operations. These criteriawill dictate the relative importance ofstrategies to be deployed for heating,heat rejection, lighting, and, in somecases, hot water. The term heat rejection is used (as opposed to cooling) based onthe idea that a fundamental goal of low-energy building design is to greatly mini-mize the need for, and dependence on,mechanical cooling.

It is important for those involved in Fed-eral design projects to know how andwhy office buildings, courthouses, labo-ratories, hospitals, visitor centers, borderstations, warehouses, and various resi-dential building types use energy. Eachof these will be summarized later, butfirst, some background informationshould prove useful in forming a basis of understanding.

Perhaps the most basic division is that ofhouses and larger, non-residential build-ings. Houses are the most commonexample of skin-load-dominated build-ings, because their energy use is predi-cated by heat gain and loss through thebuilding enclosure or skin (also knownas the envelope, e.g., walls, windows,roof, floor). Houses and other skin-load-dominated buildings primarily requireheat in cold climates, cooling in hot cli-mates, and very little energy of any type(except hot water) in benign climateslike San Diego. For low-energy perform-ance, it is common for houses and otherskin-load-dominated buildings to bewell-insulated and to invite the low win-ter sun in while keeping it out (throughshading and proper building orienta-tion) during the summer.

Simplistically, larger non-residential orcommercial buildings are often referredto as internal-load-dominated buildingsbecause a large portion of their energyuse is in response to the heat gains frombuilding occupants, lights, and electricalequipment (e.g., plug loads for computers,copiers). As a result of these internal heatsources, internal-load-dominated build-ings are often designed to turn theirbacks on the sun, and further reducesolar gain through the use of tinted andreflective glass. There is some logic tothis, but such an approach is too univer-sal and precludes some of the most ben-eficial low-energy design strategies.Moreover, it often is too simplistic tothink of a building with offices as simplyan office building. The structure is alsolikely to have a lobby and circulationspaces, a cafeteria, a computer room,meeting rooms, and other spaces thathave environmental needs and thermalcharacteristics that are very differentfrom those of offices. Ideally, designstrategies should first satisfy the needsof each individual space or zone. Thisrequires careful attention during theprogramming phase of the project.

Evaluating a specific project for selectingand integrating low-energy designstrategies starts with an understandingof the following factors:

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Climate

Not just is it hot or cold, but how humidis it? Is it predominantly clear or cloudy,and during what times of the year? Clearwinter climates are well matched withspaces that incorporate passive solarheating strategies. In contrast, spaces(and buildings) in clear summer climatesgenerally require a high degree of suncontrol. Clear climates also make thebest use of light shelves—horizontalsurfaces that bounce daylight deeperinto buildings. Even the site-specific and seasonal nature of the wind needs to be understood if natural ventilationstrategies are to be incorporated into abuilding design.

Internal Heat Gains

The heat gains from building occupants,lights, and electrical equipment can bethought of as the interior climate andshould not be generalized. Instead, dur-ing the early programming of the proj-ect, the heat gains anticipated from thesesources should be quantified for the var-ious spaces where they apply. In somecases, such as in storage buildings andother areas with relatively few occu-pants and limited electrical equipment,these heat gains will be minor. In otherinstances, the presence of intensive andenduring internal heat gains may be adetermining factor in HVAC systemdesign. Examples of intensive andenduring influences include activity-based gains, such as those produced bycafeterias and laundry facilities (whereincreased humidity is also a factor), andtechnological or industrial gains, such as the heat produced by mainframecomputers or heavy machinery. Thesefactors should be identified early on,and appropriate design strategies inves-tigated (such as heat recovery or using a closed-loop heat pump system).

Building Size and Massing

In a low-energy building, both theindoor and outdoor climates exert apowerful influence on all aspects ofbuilding design. Sometimes, they com-plement one another, such as the case of a building with a lot of internal heatgains sited in a very cold climate. At

other times, however, the two climatesare antagonistic, such as when there area lot of internal heat gains in a very hotclimate. Understanding the implicationsof these factors is fundamental to deter-mining appropriate low-energy designstrategies for a particular building proj-ect. Under hot/hot conditions, buildingswith large footprints and a large amountof floor space far from the exterior of thebuilding will require heat removal in theinterior zones (generally by mechanicalcooling) all or much of year.

The other basic planning approach is toposition all spaces that can benefit fromconnection to the outdoors in proximityto exterior walls. To achieve this, build-ings become much narrower, with amaximum width of about 70 feet. Suchan approach to building massing must,by necessity, be introduced very early in the design process. Also, recognizethat not all spaces need or want to beexposed to the exterior, including manyareas of complex building types like hospitals and courthouses. These spacesoften function better as interior place-ments within a wider and more compactbuilding form.

Lighting Requirements

The lighting needs of a building’s variousspaces need to be identified, both quan-titatively and qualitatively, as part of theenvironmental programming conductedearly in the project. Many spaces, includ-ing lobbies and circulation areas, requiregeneral ambient lighting at relativelylow foot-candle levels (10 foot-candlesor less). Such spaces are ideal candidatesfor daylighting. In contrast, some spacesare used for demanding tasks that requirehigh light levels (50 foot-candles or more)and a glare-free environment. Here thedesign team’s attention may shift fromdaylighting to a very efficient electricallighting system with integrated occu-pancy sensors and other controls.

Hours of Operation

Typically, on a per-square-foot basis, themost energy-intensive Federal buildingtypes are those in continuous use, such as hospitals and border stations. In thesebuildings, the balance of heating and

heat removal (cooling) may be altereddramatically from that of an office build-ing with typical work hours. For exam-ple, the around-the-clock generation ofheat by lights, people, and equipmentwill greatly reduce the amount of heat-ing energy used and may even warrant a change in the heating system. Intensivebuilding use also increases the need forwell-controlled, high-efficiency lightingsystems. Hours of use can also enhancethe cost effectiveness of low-energydesign strategies, such as daylightingin a border station or weather station. In contrast, buildings scheduled foroperations during abbreviated hours(including seasonal occupancy facilities,like some visitor centers), should bedesigned with limited use clearly inmind.

Energy Costs

The cost for energy, particularly electricalenergy, for most non-residential build-ings is a critical factor in determiningwhich design strategies will not onlyconserve energy, but will also be costeffective. In most locations in the UnitedStates, electricity is three to four timesmore expensive than natural gas per Btu. This disparity can, at times, be capi-talized upon by introducing designstrategies that effect a trade-off in energyuse. For example, increasing the glassarea and the commensurate daylightentry can save expensive electrical usebut, at the same time, occasion the pur-chase of additional (but relatively low-cost) heating energy. However, such anexample should not be misconstrued asindicating that daylighting requires anexcessive amount of glass, as that is justnot the case. Daylighting primarilyrequires placing the glass carefully and selecting the appropriate glazing.

In many locations, utility deregulationimposes an uncertainty on future electri-cal and other energy prices. To the great-est extent possible, the life-cycle benefitsof various design strategies should beinvestigated for the range of energy-costscenarios deemed plausible. For somestrategies—particularly those that affectthe amount of heating energy used—

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deregulation may be of lesser importance.In other cases, however, rate structures,particularly those based on peak electri-cal demand, may significantly affect theeconomic impact of strategies such asdaylighting.

As part of a whole-building design strat-egy, purchasing bulk green powerresources complements many building-specific design measures. Through aholistic approach to building design andoperation, incorporating green powerresources can further decrease the envi-ronmental impacts already minimizedthrough the specification of energy effi-ciency and renewable energy measuresin the design process. Minimizing elec-trical load requirements, and then meet-ing these requirements with clean elec-tricity resources, is at the core of awhole-building design strategy.

Green power refers to utility-scale elec-tricity resources that are in some wayenvironmentally preferable to conven-tional system power. The terms greenand clean are often used interchangeablyto describe this type of electricity. Greenpower supplied from the utility gridmay be comprised of electricity from one or more types of renewable sources.

The term renewable power refers to elec-tricity generated from one or more of the following types of resources:

•Wind—generated from wind-poweredturbines, often grouped together intowind farms

• Solar—typically generated from pho-tovoltaic (solar cell) arrays, often placedon rooftops

• Geothermal—generated from steamcaptured from below the earth’s surfacewhen water contacts hot, undergroundrock

• Biomass—burning of agricultural,forestry, and other byproducts (includ-ing landfill gas, digester gas, and munic-ipal solid waste)

• Small hydroelectric—generated fromdams with a peak capacity of less than30 megawatts (MW).

Building Types: Characteristics andProfilesThe following brief descriptions givebroad categories of building types andsome likely successful strategies for consideration.

Residential Buildings

In cold climates, the classic, skin-load-dominated building type really benefitsfrom using high-performance, low emis-sivity (low-e) windows and high levelsof insulation. In many cold climates, residential buildings can also signifi-cantly benefit from passive solar heat-ing, so long as a reasonable amount ofheat-absorbing thermal mass is incorpo-rated into the design. In hot climates,solar control is paramount, based on theneed to keep cooling loads and costsunder control. It is also important to take advantage of the opportunity forpassive or active solar water preheating.For remote structures that do not haveeasy access to the utility grid, photo-voltaic systems should be considered asthe primary, or sole, source of electricity.

Small Non-Residential Buildings

This profile describes buildings in whichlighting and internal gains play a rela-tively small role in the building’s energybalance. Such buildings are the heartand soul of low-energy building design,as a multitude of low-energy buildingdesign strategies can be successfullyapplied to their construction. One com-mon Federal building type that falls into this category is the visitor center.

Visitor centers are among the mostadvanced energy-conserving structures.They generally have a robust budget,allowing the purchase of durable mate-rials. They are normally located in severe

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Natural Gas:Typical Cost for One Million Btu

1,000,000 Btu

100,000 Btu/Therm* x 0.75 (Heating System Eff.)

Electricity:Typical Cost for One Million Btu

1,000,000 Btu

3413 Btu/kWh x 1.00 (Site Eff.)

kWh = kilowatt-hour

X $0.60/Therm = $8 per million Btu

X $0.08/kWh = $23 per million Btu

An example of an energy-efficient home in a cold climate using direct-gain passive solar heating.

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(either hot or cold) climates inaccessibleto utilities; they have a natural connec-tion with the outdoors; and the struc-tures present an opportunity to interpretthe resource-conservation mission of the agency to the visiting public. Thesestructures typically combine a need forwindow area, massive construction, anda tolerance for temperature swings—allof which are highly compatible withlow-energy building design. Daylight-ing is another key strategy for deploy-ment in these building types.

Urban Office Buildings

This building type evinces characteristicscommonly found in major urban centers,where Federal office buildings are oftenlocated. Land is often expensive andmust be used at a high density. Thebuilding is typically dominated by onerepetitive use—office space—although it may also contain a number of otheruses, such as support facilities. Thesebuildings are often landmarks or show-pieces. In highly controlled areas likeWashington, D.C., this translates intoheight limits and tight controls overfaçade treatment. In most cities, how-ever, there are few controls on the styleor height of downtown office buildings.

As a result, many of these buildingsinclude or consist of towers that shadeand are shaded by neighboring build-ings, a factor that may significantly

affect the design and sizing of themechanical cooling system.

Curtain walls are, by far, the most com-mon enclosures for downtown officebuildings, but most curtain walls areclassic examples of a “building as afortress against the environment” philosophy. The low-energy buildingdesign strategy for flat curtain walls istypically defensive in nature, limitingthe boring and often unattractive resultfrom the overuse of glass and by a lackof orientation-specific façades. Fortu-nately, there has been somewhat of a stylistic revolt against all-glass build-ings, which has led to more articulatedfaçades, variation in building façadetreatments, and a resurgence in the useof masonry. All of these factors greatlyenhance low-energy building designpossibilities by creating opportunities to tune façades to suit their orientationand the activities taking place behindthem. In most cases, thoughtful strate-gies will be needed to reduce solar gain.Exterior sunscreens or new glazingtypes (fritted, shaded) can both enliventhe façade and provide substantial cool-ing load reduction.

An excellent way to take advantage oflow-energy building design is to moveas many private offices away from thefaçade as possible. In this way, morelight can be directed further into thebuilding, and more of the building’susers can enjoy access to views and natural lighting. This scenario oftenyields increases in productivity andenables the adoption of more energy-efficient HVAC strategies.

If an atrium serves the program’s needs,it should be located and designed tosubstitute natural lighting for artificiallighting, to minimize cooling loads, andto take advantage of solar heating, if it is needed. The location and shape of theatrium will be highly building-specific.In general, taking full advantage of theunique opportunities of each urban siterequires considerable expertise, particu-larly because of shading from surround-ing buildings and the complex inter-actions among lighting, HVAC, façadedesign, orientation, and climate.

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The Zion Visitor Center is designed to use 70% less energy than a typical building withoutcosting more to build.

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Boston Edison joined Northwestern Univer-sity to use solar electricity to power the EllStudent Center on the University’s Bostoncampus. The rooftop PV system incorpo-rates 90 285-Wp modules installed on inno-vative ballasted mounting trays that requireno roof penetration.

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Courthouses

This building type typically entails high-ly complex and interrelated space pro-gramming. Many diverse functions mustbe accommodated, sites are often con-stricted, and the professional occupantsare demanding. In addition, courthousesoften serve a ceremonial function. Inmany cities, they are the most presti-gious and conspicuous of Federal build-ings. Their typically urban location oftenrequires a sensitivity to surroundingbuildings with historical styles and valueand most certainly will require carefulintegration into the existing urban plan.Oftentimes, the functional needs ofcourthouses (i.e., security requirements)must be fully satisfied before energy-based programming concerns can beaddressed, and solar design strategiesmay not always apply to this buildingtype. Still, low-energy design opportuni-ties abound, especially in terms of effi-cient lighting, HVAC systems, equip-ment, and controls. It is also worthwhileto note that many of the design issuesdescribed for urban office buildings will also apply to courthouses.

Hospitals

These facilities tend to have a lot of smallspaces, many of which need to be win-dowless. Offices and patient rooms canbe thought of as small, mixed-use areasthat incorporate both residential andcommercial features. Cafeterias and pub-lic lobbies present special opportunitiesfor daylighting. Overall, this buildingtype has many spaces that require large

quantities of outside ventilation air. There-fore, ventilation-air heat-recovery systemsthat are not prone to cross-contaminationare particularly useful in these applica-tions— especially in very cold climates.The around-the-clock nature of hospitalsis a perfect opportunity to incorporatevery efficient and well-controlled light-ing and power systems.

Laboratories

Laboratories are an energy-intensivebuilding type that often consumes morethan 200,000 Btu per square foot, due tolarge ventilation requirements and inpart to the long operating hours (two orthree shifts) that are typical. The labora-tory working environment normallyrequires enormous amounts of ventila-tion air to ensure good indoor-air qual-ity, often making heat recovery systemscost effective.

If there is a considerable demand for hotwater, preheating the water using solarenergy is recommended, particularly for

facilities located in clear climates. Thisbuilding type can often benefit from day-lighting, but because the walls tend to beoccupied with equipment, it is appropri-ate to consider either high windows ortoplighting by roof monitors on theupper floor. Either way, avoiding glare is crucial. Circulation corridors alongsouthern façades can function as solar-heated sunspaces. Sunlight on southfaçades can be “bounced” through highglazing by way of light shelves. Depend-ing on the regional climates, thermalmass walls for heat storage between labsand corridors may also make sense. Thecorridors can double as pleasant meetingand lounge spaces, while serving as abuffer to the south sun, thus permittingwider temperature swings than wouldbe permissible in the main labs. Onnorth-facing walls, small, well-spacedview windows can double as a source of diffuse daylight.

Incorporating atriums into laboratorybuildings also makes sense, both as ameans of bringing natural light into the labs and providing casual meetingspaces adjacent to the labs. West façadesmay serve as good locations for window-less lecture halls. Cafeterias can usedirect gain, or in some temperate cli-mates, might even have a fabric roof.

Warehousing/Shipping/Repairing

These activities are typically carried out in one-story buildings with high ceilings.Offices, supervisory booths, employeeservices, restrooms, and loading docksoften complement a main unpartitionedspace. For roof and wall assemblies,steps must be taken to counteract heat

A courthouse in St. Paul, Minnesota.

The National Renewable Energy Laboratory’s Solar Energy Research Facility.

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loss due to continuous metal contactsthroughout the construction. Thoughnot limited to metal components, thisprocess is known as thermal bridging,which can significantly compromise the resistance value of insulation. In climates with hot summers, a white or reflective roof is advisable.

If lighting can be controlled electronicallythrough light sensors and other devices,natural lighting strategies can be veryuseful. If the budget does not allow forproper roof monitors with vertical glassfacing south or north, consider usinghigh windows along the south and northwalls with south-facing glass shaded byproperly designed overhangs. Exercisecare in using scattered skylights, as theycan create glare and let in excessiveamounts of solar heat.

If the building is subject to around-the-clock use, large high-intensity discharge(HID) lamps are appropriate whenarranged in such a way as to lightbetween inventory stacks when daylightis unavailable. Interior surfaces shouldbe light-colored to reflect light. If thebuilding is used intermittently, moreand smaller HID or fluorescent lampsthat easily switch on and off should beused. HVAC should be localized to work areas, with the overall buildingmaintained at the maximum tempera-ture range needed for its contents andthe proper operation of machinery.

Campus Layout

This profile describes a wide variety ofbuilding types where space adjacencyrequirements are not crucial, and there is ample site area availability. Possiblebuilding types include rural or suburbanoffice buildings, training and classroomfacilities, some laboratories, barracks,and other multi-family housing.

If the buildings can be spread out, moreof the interior space will be close to anoutside wall. A campus plan makes themost sense in designing buildings forhousing and classroom use, where deep interior spaces are inappropriate.Compared to a compact building form,the campus plan generally costs more at the outset, based on the need for alarger site, the cost of added buildingenclosures, and added lengths for serviceconnections. When life-cycle economicsare taken into account, these additionalcosts can be justified if the additionalexposure is used to optimum advantageand daylighting and natural ventilationare brought into play.

For spaces that can benefit from passivesolar heating, it is essential that south-facing solar glazing be clear of any shade during the heating season, evendeciduous trees. The bare branches oftrees can change a sunspace from onethat provides useful heat into one thatdoes not. In very cold climates, it isworth considering a partially earth-sheltered building, especially in the context of a sloping site.

Renovations

Renovating and reusing a building makesit low energy and sustainable in anothervery important way. Much less energy isneeded to produce construction materi-als and deliver them to the site when thebuilding’s basic shell is being reused.Older buildings, in particular, oftenmake excellent candidates for low-energydesign that utilizes their mass, higherceilings, and narrower building form.Many aspects of low-energy buildingdesign are applicable to many large-scale renovation projects. The onlystrategies that are clearly precluded arethose based on siting, building form, ororientation. While these established fea-tures can limit a building’s low-energyperformance potential, renovations canstill reduce energy costs by 20% to 30%.

Integrating Low-Energy Conceptsinto the Design Process

Feasibility Phase

The feasibility phase is normally whenFederal building managers or other deci-sion makers in the Federal sector deter-mine that a project will be built to addressa particular need. At this stage, the enabling premises of low-energy designand construction need to be defined andestablished. Think of this as the timewhen the seeds of the overall sustainabledesign and construction strategies aresown, and the framework is establishedfor decisions to be made and actions tobe taken throughout the design and construction process. Defining param-eters; establishing general goals; andidentifying policies, directives, andenabling legislation will guide and propel the process.

During the feasibility phase, architectsand engineers develop a capital projectscope and planning document that pro-vides a design program, an implementa-tion strategy, and a budget assessment.Identifying these elements early is essen-tial to establish project feasibility, sup-port project selection, and coordinateproject execution. Community plans formajor cities and surrounding areas iden-tify long-term space needs for Federal

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An example of a multi-use building.

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agencies and propose appropriate actionsto address those needs. Major projectsinvolving renovation or construction ofFederal buildings must be developed inaccordance with applicable communityplans. Agencies often conduct studies tosupport project planning or assess build-ing conditions, some of which may takeinto account coordination with state andlocal authorities, community groups,and others who may have a stake in thedevelopment process.

Because Federal policy calls for coopera-tion with state and local authoritieswhen planning Federal facilities, localgovernment officials must be contactedto ensure that all documents impactingthe project are discussed. These docu-ments may include master plans, currentand future land-use plans, zoning maps,traffic studies, and other documents thataddress the availability of essential sup-port services (e.g., fire, police, utilities,telecommunications). Helpful informa-tion can also be obtained from youragency’s local office, including docu-mentation of current building condi-tions, maintenance concerns, site access,communication with other agencies, andother potential impacts on project scopeand implementation.

Action Items

• Conduct all required feasibility analy-ses (including, but not limited, to thosedescribed above).

• Review all existing directives and poli-cies to be sure of what your agency cur-rently requires in the way of energyperformance, materials usage (i.e., quality,durability, recycled content, energy sav-ing features, impact on indoor environ-mental quality [IEQ]), daylighting, useof renewable energy sources, contractingissues, and other relevant concerns.

• Select an energy champion and givethem the authority to make decisionsrelating to low-energy design and con-struction practices.

• Establish explicit energy-use targetsthat surpass those described in 10 CFR435; specifically, reference ExecutiveOrder 13123. Factor in any additional

criteria that may be specific to youragency or organization, facility location,or end use.

• Identify and list your agency’s goalsfor other sustainable issues, such as siteplanning, materials use, water use, orIEQ.

Budgeting Phase

Some projects may be constructed usingstandard designs (those completed forsimilar projects or off-the-shelf, prefabri-cated structures). Be certain that yourspecific low-energy goals have beenaccounted for.

Action Items

• Program any special requirements intoyour budget submission.

• Submit a budget that allows for anenergy champion (as well as the meet-ings and other resources required toaccommodate a team process), the addi-tional studies, analyses, and verifica-tions that will be needed, and slightlyhigher design fees (generally 2%–4%).

• Include the requirement for an energyexpert in your Request for Proposal/Architectural & Engineering (RFP/A&E)solicitation.

• Conduct a design charrette prior toconcept development to ensure thatlow-energy building components andstrategies will be adopted early in theplanning and design stages, when theseelements can be incorporated at the low-est possible cost.

• Identify the certification and testingmeasures required to ensure compliancewith energy targets and sustainabilitygoals.

Project Pre-Planning Phase

At inception, and during the early phasesof a low-energy project’s time line, a needsassessment is conducted (often with theassistance of a consultant). This processconsiders the long-term requirements ofthe building occupants and yields a pro-gram for the project that includes:

• User group needs and square footagerequirements

• Location and site options

• Estimated costs and schedule.

For many Federal agencies, it is essentialthat the budget established at this timebe based on all factors that will influencecosts, including the incorporation oflow-energy design strategies.

Action Items

• Select appropriate candidate low-energydesign strategies.

• Associate these strategies with the par-ticular project phase during which theymust be considered and evaluated.

• Identify the team members who willbe responsible for evaluating and incor-porating the strategies at each phase.

• Identify the appropriate evaluationtools to use at each phase and who willuse them.

• Identify the actions to be taken by var-ious team members at each phase andcarry them out.

• Establish low-energy design as a coreproject goal.

• Use case studies and passive solar per-formance maps to help determineappropriate strategies for the specificproject type at hand.

• Establish energy-use targets that sur-pass applicable codes and standards. Ingeneral, energy-use reductions in non-residential buildings should be targetedat 30% or better in comparison to a stan-dard, code-compliant building.

• Ensure that the planned building con-figuration takes maximum advantage of the site and climate.

• In selecting consultants, consider theirlevel of experience and expertise in low-energy design.

Strategies to Consider During ThisPhase

User Energy Needs Assessment

Description: This is a direct assessment of the energy-related needs of facilityusers. Whether it is in the form of anEnvironmental Programming Matrix

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or other, less formal, documentation, it isa fairly rigorous and thorough evaluationthat considers occupancy, operatinghours, and all aspects of the interior and exterior climates.

Goal: The needs assessment yields moreprecise energy use requirements, which,in turn, helps determine the applicabilityof low-energy building strategies.

Best Applied: The needs assessment isappropriate for use on all projects.

How to Do It: Classify users on the basisof specific needs that directly relate tospecific low-energy building strategies.In addition to temperature, humidity,and general lighting standards, focus on other user needs such as the desirefor exterior views and natural daylight;tolerance to moving air and temperatureswings; and the type of automatic light-ing control that is most appropriate for a given user.

Related Strategies: The needs assessmentis considered a prerequisite to almost allother strategies.

Comments: This document may be seenas an expansion of the typical needsassessment procedure, and as such, mayentail revision(s) to standard agencyassessment protocols. Coming up withuseful questions to ask in the needsassessment requires an understandingof the effects of various low-energydesign strategies on user comfort.

Building-Appropriate Site Selection

Description: This process involves choos-ing a site that fully supports the energyreduction strategies contemplated forthe project.

Goal: Proper siting increases the likeli-hood that many other low-energy build-ing strategies can be implemented.

Best Applied: This strategy is appropriatefor all new building projects.

How to Do It: During site selection, locatebuildings that do not require extensiveexterior exposure on shaded or confinedurban sites. Buildings that will benefitfrom a greater degree of exterior expo-sure should be located on open sites.

Related Strategies: See Extended Plan.

Comments: For many projects, the sitemay have been selected before the man-ager’s involvement.

Complementary Building Uses

Description: This process involves defin-ing the nature of the facility and thenmatching the end use with complementa-ry energy needs and minimizing theresulting wastes.

Goal: The design team takes advantageof the natural symbioses and commonal-ties that exist between building uses thatmight otherwise be overlooked.

Best Applied: When compatible projectsare at similar points in their development;ideally, from the planning stages forward.

How to Do It: At the earliest stages ofproject conception and site selection,consider co-locating any types of facili-ties where the waste products of one can be used to provide needed energyfor another, or where construction-based support services can be shared.

Related Strategies: Building-AppropriateSite Selection; User Energy NeedsAssessment

Comments: Currently used in designingco-generation facilities, ecological indus-trial parks, district heating, and commu-nity-scale energy storage facilities; otherapplications may be identified on a case-by-case basis. Opportunities may alsoexist for co-locating non-pollutingindustrial and residential facilities. In all circumstances, action is required atthe earliest stages of the project, beforedetailed plans for the various uses arefully developed.

Project Planning Phase

In close consultation with agency projectpersonnel, the design consultants (e.g.,architects and engineers) prepare initialand schematic design options. At thistime, options for placing the proposedbuilding(s) on the site and massing alter-natives are evaluated. Fundamental low-energy design strategies (as detailedbelow) are also assessed for applicabilityto a specific project. Design consultants

generally present their design options andanalyses to agency project personnel forreview and evaluation; this process isoften repeated several times until thebasic design is decided upon andapproved. At the conclusion of thisphase, the design should clearly indi-cate which low-energy design strategieshave been incorporated in sufficientdetail so that heating and cooling loadscan be estimated and so HVAC systemoptions can be examined.

Action Items

• Establish an interdisciplinary designteam, including an energy professional, as early in the process as possible.

• Develop a preliminary layout thatmaximizes or minimizes solar gain.Consider atrium spaces, direct or indi-rect passive solar heating, earth-protected spaces, and natural andconstructed shading.

• Develop landscape plans that con-tribute to the facility’s energy perform-ance. Consider shading options, windbreaks, and using existing site features.

• Develop a basic layout that maximizesthe use of daylighting. Consider buildingorientation, the size and placement ofwindows, and toplighting.

• Investigate using renewable powersources as part of the facility’s overallpower supply. Consider using solar(domestic) hot water on building typeswith high hot water usage (such as labo-ratories) and building-integrated photo-voltaics (BIPV) to reduce reliance onnon-renewable power.

• Conduct a preliminary energy analysis(analysis tools depend on scale of proj-ect). Use ENERGY-10 and other user-friendly tools for smaller, simpler projects(those with two or fewer zones, androughly 50,000 square feet or less). UseDOE 2.2 and other applicable tools forlarger and more complex projects.

Strategies to Consider During ThisPhase

The following strategies need to beassessed during the project planningphase of the time line. Their incorpora-

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tion will influence the overall siting andmassing of the building, as well as thebasic organization of spaces.

Perimeter Circulation Space

Description: This passive solar strategyuses circulation (corridors) and casualmeeting spaces as buffers between thefaçade and the interior conditionedspaces.

Goal: To support several low-energybuilding strategies that are not compati-ble with certain uses (e.g., direct-gainsunspaces and office space).

Best Applied: The strategy is appropriatein buildings needing large areas for cir-culation, waiting, and casual meetings,such as a visitors’ corridor in a hospitalor casual meeting sunspaces outside laboratories or offices.

How to Do It: Because perimeter circula-tion plans generally require slightlymore total floor area, it is necessary toexamine user needs and evaluate thestrategy in light of the overall budget. If the strategy is acceptable, look forbuffer spaces that can be located alongthe building’s exterior, particularly along the south façade.

Related Strategies: Atrium Spaces; OpenOffice Space at Perimeter; Direct-GainPassive Solar Heating; Daylightingthrough Windows; Light Shelves;Selective Glazing; Shading Devices;Window Geometry; Natural Ventilationthrough Windows.

Comments: An accurate energy needsassessment is key to the effective inte-gration of this strategy.

Extended Plan

Description: By extending the plan to pro-duce a longer, narrower footprint, youcan create more exterior wall surface. Inmost climates, elongating the building in an east-west direction makes the mostsense from the standpoint of daylightingand passive solar heating.

Goal: To increase the amount of usablespace that is close to an outside wall.

Best Applied: Building types that benefitmost from exterior exposure include

good candidates for daylighting anddirect-gain passive solar heating.

How to Do It: This is best accomplishedearly in the design process, as modifyingthe basic building form may occasion aslight increase in the construction budget.

Related Strategies: Atrium Spaces; OpenOffice Space at Perimeter; PerimeterCirculation Space; Daylighting throughWindows; all forms of Passive SolarHeating; Building-Appropriate SiteSelection; Landscape Shading; LightShelves; Shading Devices; NaturalVentilation through Windows.

Direct-Gain Passive Solar Heating

Description: Installing south-facing glaz-ing in an occupied space enables the col-lection of solar energy, which is partiallystored in the walls, floors, and/or ceilingof the space, and later released.

Goals: With direct-gain passive solarheating, the savings achieved in heatingenergy is augmented by the aestheticand productivity-enhancing benefits of daylighting, a valuable amenity for occupants. The functioning of the spaceshould not be compromised by directglare from glazed openings or by localoverheating.

Best Applied: This strategy works well incold, clear climates.

How to Do It: Glazing must face within 15 degrees of true (solar) south, and theaffected areas must be compatible withdaily temperature swings.

Examples: Some appropriate contexts fordirect-gain heating include corridorspaces, eating spaces, meeting spacesthat can be scheduled for use duringtimes when the temperature is mostcomfortable, sleeping spaces, and recre-ational sunspaces. Working with theenergy consultant, the designer can finetune the amount and type of glazingwith glare and temperature controls,materials in the affected space, auxiliaryheating, and cooling to address local climatic changes.

Related Strategies: Atrium Spaces; Differ-entiated Façades; Extended Plan; Perim-eter Circulation Space; Daylightingthrough Windows; Building-Appropri-ate Site Selection; Landscape Shading;Selective Glazing; Shading Devices;Window Geometry.

Comments: Because true north and mag-netic north are different, the design teamwill need to account for magnetic decli-

An example of direct-gain passive solar used in a residential building.

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nation. For optimum effect, floor andwall finish materials with high heat-storage capacity must be exposed todirect illumination by the low wintersun. Overall, this strategy is consideredcentral to low-energy building design.

Atrium Spaces

Description: Atrium spaces are multi-floor open areas appropriate for circula-tion, lobbies, dining, or other sharedspace. Atriums are typically covered by a glazed roof or one that incorpo-rates roof monitors.

Goal: Configure the atrium for minimumimpact on the building’s energy load.

Best Applied: Buildings with programmedspaces that can be well-served by one ormore atrium spaces.

How to Do It: Avoid configurations thatproduce heat losses or gains with nocompensatory benefits. The atriumshould bring daylight to the interior ofthe building while providing a “chim-ney” for natural ventilation during mildweather. In some cases, atriums can col-lect useful solar heat in cold climates—serving as a kind of transition zone, withlarger temperature swings than wouldotherwise be appropriate in the rest of

the building. The atrium’s configurationshould be defined at the earliest possiblestages of the design process, before anundesirable or arbitrary configuration is locked in.

Related Strategies: Building-AppropriateSite Selection; Extended Plan; PerimeterCirculation Space; Roof Monitors; GlazedRoofs; Fabric Roofs; Direct-Gain PassiveSolar Heating; Selective Glazing; ShadingDevices; Induced (Stack-Effect)Ventilation.

Comments: There is no hard and fast dis-tinction between atriums and glazedroofs over large open spaces (such asgallerias).

Induced (Stack-Effect) Ventilation

Description: Heated air rises within amid- or high-rise building to the top(often below a glazed roof in an atrium),where it exits through roof openings.This process induces ventilation of theadjoining spaces below.

Goals: This strategy removes heat andreduces mechanical cooling and fanenergy use requirements.

Best Applied: Spaces that are not adverselyaffected by increased air motion areappropriate targets for natural whole-building ventilation, which effectivelyconditions the space during fair weatherwithout using air conditioning.

How to Do It: Incorporate air inlets, gen-erally in the form of operable windows,at the building perimeter. For best results,use open-office space planning andavoid partitions that inhibit air move-ment. Consider complementing naturalventilation with controllable passiveventilators located in the upper portionsof the building. Carefully coordinate theimplementation of this strategy withbuilding HVAC system and controls.

Related Strategies: Atrium Spaces; GlazedRoofs; Roof Monitors; Natural Ventila-tion through Windows; Night-timeCooling Ventilation.

Comments: Natural ventilation worksbest in low-humidity climates. An atri-um often serves as an ideal chimney toexhaust hot air.

Open Office Space at Perimeter

Description: Locating private offices atinterior positions leaves the perimeteropen to general office space.

Goal: Program open spaces at the peri-meter to allow for more extensive use ofdaylighting deeper into interior sections.

Best Applied: Use this strategy in build-ings with large areas of office space.

How to Do It: Private, interior-locatedoffices need compensating amenities. Atminimum, install glazing that lets ontothe open office space or overlooks anatrium space. This strategy is especiallyappropriate for buildings with limitedfaçade glazing, such as earth-protectedbuildings.

Related Strategies: Atrium Spaces; Earth-Protected Space; Perimeter CirculationSpace; Daylighting through Windows;Light Shelves; Selective Glazing; ShadingDevices; Window Geometry; NaturalVentilation through Windows.

Comments: This is an effective strategythat requires a strong commitment bythe agency or organization to keepperimeter spaces open and not reservethem for high-ranking executives. (Thisis perhaps not as significant an issue inFederal buildings as compared to theprivate sector.)

Landscape Shading

Description: The use of existing orplanned trees and major landscapingelements to provide beneficial shading.

Goal: Locate trees and major landscapeelements to provide useful shading andreduce cooling loads.

Best Applied: Landscape shading worksbest when shading west and southfaçades.

How to Do It: Study planting plans ofexisting site landscaping to determinewhether existing trees can be retainedand incorporated into the planningprocess. Perform shading analyses ofplants in both immature and matureforms to estimate energy savings duringplants’ anticipated life span. Wheneverpossible, avoid or remove plantings thatwould compromise useful solar gain.

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An example of an atrium space.

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Related Strategies: Atrium Spaces; Day-lighting through Windows; all forms ofPassive Solar Heating; Building-Appro-priate Site Selection; Selective Glazing;Shading Devices; Natural Ventilationthrough Windows.

Comments: Trees and landscaping canreduce peak cooling loads through shad-ing and can cool the ventilation airentering a building. Even during thewinter, most deciduous trees and plantscast substantial shade on solar collectors(e.g., south-facing windows).

Earth-Protected Space

Description: Bermed, or partially buried,construction can moderate buildingtemperature, save energy, and preserveopen space and views above the building.

Goals: To minimize heating and coolingenergy use by protecting more of thebuilding from fluctuating outdoor airtemperatures.

Best Applied: Sites with a large naturalslope in cold climates are ideal candi-dates for incorporating earth-protectedspaces.

How to Do It: Berm against walls or earth-cover roofs (in severely hot or cold cli-mates) or combine high horizontal win-dows with light shelves located aboveearth-sheltered walls. In some cases,

using "invisible" earth-protected build-ings can help counter community resist-ance to bulky new construction.

Related Strategies: Open Office Space atPerimeter; Roof Monitors; Building-Appropriate Site Selection; LandscapeShading; Insulation.

Comments: Similar low-energy perform-ance can also be achieved by using addi-tional insulation.

Solar Water Heating

Description: Solar water heating usesflat-plate solar collectors to preheatdomestic hot water.

Goal: To be considered effective, thisstrategy should yield a significant por-tion (50% or more) of the domestic hotwater needed for day-to-day operations.

Best Applied: Look to building typeswhere hot water use is high year-round,such as hospitals and laboratories. Bestperformance will be achieved in hot cli-mates with high solar radiation levels.

How to Do It: Design an array of flat-platesolar collectors that include an absorberplate (usually metal), which heats whenexposed to solar radiation. Most commonamong these are indirect systems thatcirculate a freeze-protected fluid througha closed loop and then transfer heat topotable water through a heat exchanger.Typically roof-mounted, solar collectorsshould face south and tilt at an angleabove horizontal, approximately equal

to the latitude of the project location. Thisconfiguration will provide optimumyear-round performance. Provide a pipechase to a mechanical room. The roomneeds to be large enough for storagetanks.

Related Strategies: Roof Monitors; Non-Absorbing Roofing.

Comments: Collectors should be mountedin a location that is unshaded by sur-rounding buildings or trees during thehours of 8 a.m. to 4 p.m. (at minimum)throughout the year. As is the case withmany of the strategies described herein,an effective conservation program willhelp to minimize hot water demandand, in turn, reduce material and sys-temic requirements.

Building-Integrated PhotovoltaicSystems

Description: Photovoltaic (PV) arrays arenow available that take the place of ordi-nary building elements (such as shinglesand other roofing components), convert-ing sunlight into electrical energy with-out moving parts, noise, or harmfulemissions.

Goal: Reduce the first cost of the PVarray by using it in place of high-costbuilding elements and take into accountthe energy cost reductions over time.

Best Applied: Consider deployment insunny climates with high electrical utilitycharges.

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Landscaping and trees help minimize heatgain to the building and surrounding concrete.

An example of an earth-sheltered building in Tempe, Arizona.

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How to Do It: Commercially availablesystems include thick, crystal, circularcells assembled in panels and thin-filmproducts deposited on glass or metalsubstrates. At today’s prices, BIPV oftenprovides a good payback if it replaceshigh-cost glazing, such as fritted glass (the arrays can even resemble frittedglass). To be cost effective, BIPV must intercept nearly a full day’s sun, so it isoften most effective as a replacement forroof or atrium glazing. BIPV also workswell as spandrels that are fully exposedto the sun.

Related Strategies: Atrium Spaces;Differentiated Façades; Glazed Roofs;Roof Monitors; Building-AppropriateSite Selection; Shading Devices.

Comments: One of the benefits of grid-tied BIPV systems is that power produc-tion is typically greatest (on bright, sunnydays) at or near the time of the build-ing’s peak electrical and cooling loads.

Schematic Design (or PreliminaryDesign) Phase

During the previous phase of the timeline, Project Planning, basic decisionswere made regarding site placement,plan organization, and building mass-ing. Those determinations will nowinfluence the basic low-energy design

strategies (e.g., daylighting) that will be evaluated in detail during this phase,especially those relating to the buildingenclosure (or envelope).

Traditional building design has assigneda protective role to the walls, roofs, andfloors of buildings—protection againstcold, sun, rain, and unwanted intrusion.In low-energy building design, the pro-tective role still exists, but the buildingenvelope is also thought of as a mem-brane that manages or “mediates” inter-actions between the interior spaces andthe outside environment. During sche-matic design, the Envelope-RelatedStrategies discussed below will be evaluated and integrated into the overall building design.

Action Items

• As the preliminary layout is refined,ensure that access to daylight continuesto be optimized. Consider perimeteraccess to light and views, roof monitors,skylights and clerestory windows, andlight shelves.

• Develop material specifications and abuilding envelope configuration thatmaximizes energy performance. Considerwindow shape and placement, shadingdevices, differentiated façades, reflectiveroofing, fabric roofs, induced ventila-tion, nighttime cooling ventilation, andselective glazing.

• Continue energy analyses, includingmultiple runs of similar products (e.g.,various glazings and insulation levels)to determine best project-specific options.In addition to first cost, consider dura-bility and long-term energy performance.

Strategies to Consider During this Phase

Selective Glazing for Walls

Description: Glass products are nowavailable with a wide range of perform-ance attributes that allow designers tocarefully select the amount of solar gain,visible light, and heat that they allow topass through. Solar heat is measured bythe properties of shading coefficient (SC) and solar heat gain factor (SHGF).An SC of 1.0 applies to clear 1/8-inch-thick glass with other glasses that admit

a lesser amount of solar heat having alower SC (e.g., 0.50 for a tinted glass thatadmits 50% as much solar heat as 1/8-inch clear glass). The term SHGF, whichis now widely used by the glazing (fen-estration) industry because it takes intoaccount a range of angles of solar inci-dence, is considered to be equal to avalue of 0.86 times the SC. The degree of daylight, or visible light transmission,is expressed by the term “Tvis,” and theamount of heat loss is measured by theU-factor, which, expressed numerically,is the inverse of the total resistance ofthe glazing assembly.

Single-glazing is about R-1 or 1/1 for aU-factor of about 1.0. Double-glazing isabout R-2 for a U-factor of about 0.50.Commercially available low-e glass typically ranges in U-factor from about0.35 down to 0.10, depending on thetype and number of coatings and thefills (e.g., argon) used in the spacesbetween glazing layers.

Goal: Specify glazings with the best com-bination of performance characteristicsfor the specific application at hand.

Best Applied: The choice of glazing(s) isan essential consideration for all build-ing types.

How to Do It: Begin by incorporatingglass performance characteristics (e.g.,U-factor, shading coefficient) as requiredby the applicable codes or standards.Then, use computer analysis to investi-gate alternate glazings and narrow thefield to those most beneficial to admit-ting daylight and saving energy, whilestill remaining within the project budg-et. Glazing technology has nowadvanced to the point that alternativeglazings with very different perform-ance characteristics can physically lookvery much alike. This increases thepotential to use different glass types on different façades, although such anapproach may be considered a mainte-nance headache. The best glazing selec-tions are not merely those with thehighest numerical performance levels in a given area. For example, daylightinga space with a large expanse of glass,using glazing with the highest daylight

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An example of Building-Integrated PV is 4 Times Square in New York City.

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transmission may result in excessiveglare. Fritted glass should be consideredwhen glare reduction through othermeans is difficult to achieve.

Related Strategies: Atrium Spaces; GlazedRoofs; Roof Monitors; Scattered Sky-lights; Daylighting through Windows;Direct-Gain Passive Solar Heating;Landscape Shading; Light Shelves;Shading Devices; Window Geometry.

Comments: Of the various building enve-lope components, glazing almost alwayshas the most significant effect on heat-ing, cooling, and lighting energy use. Inthe last 20 years, glazing technology hasprogressed more dramatically than per-haps any other building product or sys-tem. By using high R-factor glazing(indicating substantial resistance to heatinflow), it is often possible to eliminateperimeter baseboard heaters.

Shading Devices

Description: Fixed or movable (manualor motorized) devices located inside oroutside the glazing are used to controldirect or indirect solar gain.

Goal: Shading should be used to providecost-effective, aesthetically acceptable,functionally effective solar control.

Best Applied: This strategy works well onsouth façades where overhangs provideeffective shading for work space and canalso serve as light shelves. Shading westfaçades is critical to reduce peak coolingloads.

How to Do It: A wide range of shadingdevices are available, including over-hangs (on south façades), fins (on eastand west façades), interior blinds andshades, louvers, and special glazing(such as fritted glass). Reflective shadingdevices can further control solar heatgain and glare.

Related Strategies: Atrium Spaces; BIPV;Differentiated Façades; Open OfficeSpace at Perimeter; Perimeter CirculationSpace; Glazed Roofs; Roof Monitors;Scattered Skylights; Daylightingthrough Windows; Direct-Gain PassiveSolar Heating; Light Shelves; SelectiveGlazing; Window Geometry.

Comments: Devices without moving partsare generally preferable. Movable deviceson the exterior are typically difficult tomaintain in corrosive environments orin climates with freezing temperatures.Other building elements, such as over-hanging roofs, can also serve as shadingdevices.

Daylighting through Windows

Description: Using daylighting throughbuilding windows can displace artificiallighting, reduce energy costs, and isassociated with improved occupanthealth, comfort, and productivity.

Goal: Reduce lighting and cooling energymore than the increase in heating energyoccasioned by reduced lighting loads. (In summer, cooling energy demand is less because the heat from artificial lighting sources is reduced. In winter,the heat that is not being produced byartificial lighting may need to be com-pensated for by the building’s heatingsystem).

Best Applied: Daylighting through win-dows is best accomplished on façades

that have a generally clear view of thesky, particularly the sky at angles of 30degrees or more above the horizon.

How to Do It: Place much of the façadeglazing high on the wall, so that day-light penetration is deeper. Consider the enhanced use of daylighting byinstalling light shelves on south façades. Recognize the interdependen-cies in glazing, light fixtures and con-trols, and HVAC systems. Wheneverpossible, electrical lighting should be considered a supplement to natural light.When the sun goes down on buildingswith long hours of operation, however,efficient electrical lighting design takeson added importance.

Related Strategies: Differentiated Façades;Extended Plan; Open Office Space atPerimeter; Perimeter Circulation Space;Direct-Gain Passive Solar Heating;Building-Appropriate Site Selection;Landscape Shading; Light Shelves;Selective Glazing; Shading Devices;Window Geometry.

Comments: Daylighting is a central com-ponent of the vast majority of low-energy

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Shade from trees is a simple but effective strategy to reduce costly cooling requirements.

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buildings and, as such, merits significanttime and attention.

Extended Daylighting throughWindows—Light Shelves

Description: A horizontal device or “shelf”that bounces direct sunlight off the ceil-ing and deeper into the interior spaces.Light shelves are also used to provideshading and suppress glare. Lightshelves are located above vision glazing(up to and slightly above eye level), butbelow high glazing above. They may bepositioned inside or outside (where theyalso provide shading), or both (this istypical).

Goal: Save lighting energy, reduce glare,and provide useful shading.

Best Applied: In clear climates, lightshelves are appropriate for integrationon façades facing within about 30 degreesof true (solar) south.

How to Do It: Integrate the light shelveswith façade design, office layout, light-ing design, lighting controls, glazing,and shading devices. They tend to workbest with moderately high ceilings(about 10 feet, minimum) and openplanning.

Related Strategies: Differentiated Façades;Open Office Space at Perimeter; Day-lighting through Windows; SelectiveGlazing; Window Geometry.

Comments: Transom windows can beused to allow light from the shelves toenter interior office spaces located farfrom exterior walls. Maintenance maybe an issue, and pigeons present a con-cern in some areas.

Natural Ventilation through Windows

Description: User-controlled operation ofwindows provides outdoor air for venti-lation and cooling, and should improveindoor air quality.

Goal: A balanced approach involves tak-ing advantage of users’ desire for envi-ronmental control without interferingwith efficient HVAC operation.

Best Applied: Particularly appropriate inbuilding types and locations wheresecurity concerns and exterior noise or

air quality is not an issue. Users must be tolerant of increased horizontal airmotion.

How to Do It: Locate windows that willserve as air inlets to face prevailingwinds. During the cooling season, thisstrategy can be enhanced by landscap-ing features and projecting building fea-tures (such as fins). This strategy tendsto work best in residential-type occu-pancies, where the user already has control over HVAC.

Related Strategies: Atrium Spaces; Differ-entiated Façade; Perimeter CirculationSpace; Window Daylighting; LandscapeShading; Window Geometry; Econo-mizer Cycle Ventilation; Induced Venti-lation; Nighttime Cooling Ventilation.

Comments: A well-considered controlstrategy (either mechanical or social) is required to prevent air conditioningfrom operating in a space with openwindows. If such a control strategy can-not be devised or is not effective or real-istic because of the building occupants,operable windows can increase buildingenergy use.

Window Geometry

Description: Windows should be shapedand located in a manner that minimizesglare and unwanted solar gain and max-imizes useful daylight and desirablesolar heating.

Goal: The design team should applyfunctional criteria to the size, propor-tion, and location of windows. It isimportant to avoid incorporating morewindow area than is beneficial to thebuilding occupants or that is needed to enhance low-energy performance.

Best Applied: Shape, size, and location ofwindows are important considerationsin all projects.

How to Do It: Make window decisionsbased on occupant activities and low-energy performance rather than simplyfor aesthetic purposes. Having said this,reduce glass area whenever possible. Tominimize glare and enhance daylightingbenefits, substitute horizontal strips ofhigh windows for “punched” windows,and scattered small windows in lieu of a few large ones.

Related Strategies: Atrium Spaces; Differ-entiated Façades; Extended Plan; Perim-eter Circulation Space; Light Shelves;Selective Glazing; Shading Devices;Natural Ventilation through Windows.

Comments: The best way to evaluate thelighting effects of window geometry and configuration is through computeranalysis, using programs such as RADIANCE.

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Daylighting retrofits for U.S. Army warehouse in Hawaii.

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Differentiated Façades

Description: In this strategy, the designercreates variations in the façade design in response to changes in orientation,the use of space behind the façade, andthe low-energy design strategies beingemployed.

Goal: Strive for seamless integration ofenergy-related design strategies with theoverall aesthetic and functional designcomponents of the project.

Best Applied: If each façade is to be opti-mized, this strategy will work on almostall projects.

How to Do It: Select a design consultantwho can work with the concept that the appearance of a building’s variousfaçades will likely differ in response tovariations in their environmental loads.To that end, pursue a building style thatis compatible with functionally variedfaçade elements.

Related Strategies: Atrium Spaces; BIPV;Perimeter Circulation Space; Daylightingthrough Windows; all forms of PassiveSolar Heating; Complementary BuildingUses; Landscape Shading; Light Shelves;

Selective Glazing; Shading Devices;Window Shape; Natural Ventilationthrough Windows.

Comments: Considered as one of the mostbasic and effective low-energy buildingstrategies, using different façades is really

an approach to design and style that isdriven by function. Different façades do not necessarily have to be radicallyunique; rather, they may simply be vari-ations on a theme. For the sake of unifor-mity, designers sometimes put over-hangs on all façades, even though theymay only provide significant energybenefits on the south side. Such anapproach can greatly compromise thebasic cost-effectiveness of the strategyand should generally be avoided.

Insulation

Description: A well-insulated buildingenvelope reduces energy use, controlsmoisture, enhances comfort, and pro-tects the energy-saving potential of pas-sive solar design.

Goal: Identify the optimum amount ofbuilding insulation to use in the walls,roof, and floor construction.

Best Applied: Residential building typesin cold climates benefit most from largeamounts of insulation.

How to Do It: Begin by incorporatinginsulation levels required by code orstandard, then use computer analysis to investigate optimum insulationamounts. For buildings with mass walls,use computer analysis to determine the

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This building has differentiated façades—broad overhangs for shading on the south side andno overhangs on the north side.

This building uses a light shelf on the south side for daylighting. It also has small squarewindows on the east and west to minimize glare.

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OPERATIONS & MAINTENANCEWARRANTY PERIOD

TURN OVER TO OCCUPANTS

CONSTRUCTION PHASE (CM)

BID SOLICITATION/CONTRACT AWARDMILESTONE (100%)

CONSTRUCTION DOCUMENTSMILESTONE (95%)

DESIGN DEVELOPMENT II

VALUE ENGINEERING PHASE

MILESTONE (50%–60%)

DESIGN DEVELOPMENT I

MILESTONE (35% DESIGN)

SCHEMATIC DESIGN PHASE(OR PRELIMINARY DESIGN)

MILESTONE (15% DESIGN)

PROJECT PLANNING PHASE

PROJECT PRE-PLANNING

BUDGETING PHASE

FEASIBILITY PHASE

Action Items:

· Program any special requirements into your budget submission;· Submit a budget that allows for an energy champion, the necessary meetings to

accommodate a team process, the extra studies, analyses and verifications that will be needed, and slightly higher design fees (2%–4%);

· Include the requirement for an energy expert in your RFP/A&E solicitation;· Conduct a design charrette BEFORE concept development;· Identify the certification and testing measures you will require.

See page 13 for details on these Action Items and the strategies to consider during this phase.

Action Items:

· Conduct all required feasibility analyses;· Review all existing directives and policies to be sure what your agency currently requires;· Select an ‘energy champion and give them the necessary authority;· Establish explicit energy use targets that surpass 10 CFR 435;· Identify your agency’s goals for the other sustainable issues such as site planning, materials use, water use, and IEQ.

See page 12 for details on Action Items and the strategies to consider during this phase.

Action Items:

· Establish low-energy as a core project goal;· Establish energy use targets;· In selecting consultants, consider their level of experience;· Classify the energy-related requirements of the users;· Identify the climate and utility costs at the project site;· Identify the characteristic space and building uses that apply to the

project.

See pages 13 for details on Action Items and the strategies to consider during this Phase.

Action Items:

· Establish interdisciplinary design team;· Develop a preliminary layout;· Develop landscape plans;· Develop a basic layout;· Investigate renewable power sources;· Conduct preliminary energy analysis.

See page 14 for details on Action Items and the strategies to consider during this phase.

Action Items:

· Ensure optimization of daylighting;· Develop material specs and envelope configuration that maximizes performance;

· Continue energy analyses; determine best project-specific options.

See page 18 for details on Action Items and which strategies to consider during this phase.

Action Items:

· Continue energy analysis; ensure that performance objectives are maintained.


Action Items:

· Ensure that VE is based on life-cycle considerations;· Incorporate energy analysis directly into VE;· Ensure that energy targets are maintained.


Action Items:

· Ensure that construction details and specifications are consistent;· Ensure that mechanical equipment meets design targets;· Lighting system;· Conduct a final design review.

See page 28 for details on Action Items and the strategies to consider at this phase.

HOW TO USE THE TIME LINE:

This time line is to be used by Federal project managers to remind them when they should be thinking about low-energy, sustainable design during the various phases of planning, design, construction, and turnover of a building. Without explicit actions throughout the process, the resulting buildings will often not meet the owner’s requirements and expectations. Because each agency has its own terms for these phases, the time line uses the traditional American Institute of Architects (AIA) terminology and notes the stages at which Federal agencies often demand milestone submissions (15%, 35%, 50%–60%, and 95%). During each of these stages, there are very different opportunities to ensure, or to lose, low-energy sustainable design. This guidebook is focused primarily on low-energy issues and recognizes that low-energy does not equal sustainability. Comprehensive sustainability includes many other issues such as water use, indoor environmental quality (IEQ), and green materials.

It is assumed that whatever agency you are in already has specific directives for facility managers that provide guidance for procuring low-energy, sustainable buildingsand facilities. These directives might range from general guiding principles to more specific energy and water use targets, foot-candle levels, requirements for using renewable energy sources, and even materials criteria for each building type. It is conceivable that there might be some existing policies that are contrary to your newly emerging low-energy, sustainable goals, and these should be recognized and eliminated if at all possible.

You will need a unique perspective, one that relies on a whole-building approach to the problem. The time line suggests potential steps that will help you realize your goal of a low-energy (and a sustainable) facility. The time line will show you some new steps you will incorporate into your thinking, planning, and budgeting steps that are not needed in the traditional design process. For example, you will see the requirement for an energy champion and several stages where you have to conduct some evaluations to really understand the consequences of some very complex tradeoffs. You must be clear about the costs to have “extra” people (like the energy champion) on the job or additional costs to perform the necessary evaluations and include them in your budgets from Day One.

There will be some new roles and responsibilities if you expect to deliver a low-energy, sustainable building: you will need to state your expectations clearly and give your team the resources and the authority they need to accomplish the goals on time and within budget.

Refer to the section called “How to Apply,” which follows the time line. This section provides the details about which low-energy strategies should be considered duringeach phase. Each one notes Description, Goal, Best Applied, How to Do It, Related Strategies, and Comments for that strategy.

Action Items:

· Ensure energy features are constructed/ installed as designed.


Action Items:

· Monitor energy performance;· Implement a full commissioning protocol.


Action Items:

· Ensure that construction details and specifications are consistent;· Ensure that mechanical equipment meets design targets;· Conduct a final design review.


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relative advantages of placing the insu-lation on the inside or on the outside ofthe mass. Detail assemblies containinginsulation to avoid thermal bridges,where conductive elements (e.g., metal studs) penetrate the insulation and short-circuit the system by conducting heat. Innon-residential construction, there aremany cases, particularly in hot climates,where using more insulation to enclose a sealed building will cause it to behavelike a Thermos bottle—trapping heatand using even more energy.

Related Strategies: High-Efficiency HVAC.

Comments: The law of diminishing returnsapplies to additional levels of insulation,whereby the first increment of insulationreduces heat loss dramatically, and eachadditional increment provides less andless of an improvement. The quality ofinsulation—and how well it is installed—is very important, especially when itcomes to batt insulation in walls.

Air Leakage Control

Description: Air retarder systems areused to reduce air leakage into or out of a building.

Goal: To deploy a system that reducesenergy use and serves to protect thebuilding’s envelope, structure, and finishes.

Best Applied: Air leakage control is considered to be standard low-energyprocedure in cold climates.

How to Do It: Install air-impermeablecomponents that are sealed at the joints

and penetrations to create a continuous,airtight membrane around the building.Note, however, that air retarders placedon the winter/cold side of the insulationmust be vapor-permeable to avoid trap-ping moisture within the walls.

Related Strategies: Insulation, High-Efficiency HVAC.

Comments: Designers of many non-resi-dential building types attempt to reduceair infiltration by maintaining the indoorspace at a higher pressure than the out-side ambient air. When an air retarder isinstalled, pressurization becomes easierto achieve, while at the same time, theneed for pressurization becomes lesscritical. In masonry construction, bitu-minous membranes are sprayed or trowel-applied to serve as air retarders,with bitumen-based sheets typicallyused in curtain-wall construction.Evaluate the benefits of an air retardernot only for improved energy use, butalso for reduced wall maintenance andrepair costs. Also evaluate the air leak-age characteristics of manufacturedcomponents such as windows, doors,and curtain walls.

Roof Monitors

Description: Roof monitors are windowsinstalled at roof level, typically verticalor steeply sloped.

Goal: To admit useful natural light andoften desirable solar heat gain duringthe heating season.

Best Applied: This approach works wellon many building types, particularlylow buildings with one or two stories.

How to Do It: South-facing roof monitorsshould use vertical glass and be shadedby overhangs to provide daylight anduseful solar heating (for many buildingtypes in many locations). By contrast,north-facing roof monitors need not beconcerned with glare or the unwantedentry of direct solar rays. North-facingglazing can be inclined (tilted) some-what to access the overhead sky better,which provides a much greater level ofdiffuse daylight than does the sky nearthe horizon. As a general rule of thumb,avoid east- and west-facing roof moni-

tors. Also avoid horizontal glazing, whichtypically overheats the building, therebydramatically increasing cooling loads.Minimize the amount of glass requiredto achieve desired illumination levels,and avoid narrow slots with glazing onopposite sides.

Related Strategies: Direct-Gain PassiveSolar Heating; Selective Shading;Shading Devices; Window Geometry;Induced Ventilation; Lighting andLighting Controls.

Comments: Design guidelines are avail-able for various geometries of roof mon-itors and other toplighting strategies. To fine tune monitor locations, providequality lighting environments, andquantify resulting energy benefits, computer analysis is advised.

Scattered Skylights

Description: Small, individual spot-locatedskylights.

Goal: To obtain useful daylighting.

Best Applied: Appropriate for use in one-story buildings, such as warehouses, andespecially useful in buildings where suncontrol is of secondary importance.

How to Do It: Generally achieved withprefabricated elements that have flat ordomed glazing, spot-located skylightsshould be used with care, except in caseswhere potential glare and direct sunpenetration is of little concern within the building. Use sparingly—large num-bers of separate skylights are expensivein comparison to glazed roofs.

Related Strategies: Extended Plan;Selective Glazing.

Comments: Even when mounted aboveprefabricated or site-built wells, it isvery difficult to entirely eliminate sunpenetration when solar altitude anglesare at their highest (around the summersolstice, June 21). Guidelines for spacingscattered skylights are available, andcomputer analysis to fine-tune sizingand spacing and quantify energy bene-fits is advised. Potential roof leaks are often a concern and should be addressedby proper detailing. Despite these draw-backs, scattered, spot-located skylights

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are widely applicable to warehouses,low-rise residential, and many othersmaller buildings.

Glazed Roofs

Description: Glazed roofs are large-areaskylights typically found over atriumspaces.

Goal: To provide daylighting in a man-ner that may increase the architecturalimpact of the space while providing amore direct connection between build-ing occupants and the outside world.

Best Applied: Glazed roofs work wellabove circulation areas and other high-occupancy spaces.

How to Do It: Consider installing a clear-span glazed roof between buildings orbuilding sections to create a covered“street.” Solar heat gain can be controlledthrough use of fritted glass or louvers.

Related Strategies: Atrium Spaces;Extended Plan; Selective Glazing;Shading Devices; Induced Ventilation.

Comments: Excessive cooling loads frequently accompany this designapproach. When used over high spaces(such as atriums), incorporate inducedventilation strategies whenever possible.As a secondary option, mechanical cool-

ing should be provided through a dis-placement ventilation approach, whereonly the air in the occupied zone of thespace near the floor is conditioned.

Non-Absorbing Roofing

Description: Roofs covered by light-colored or reflective membranes are aviable passive solar strategy, as theytend to absorb less heat.

Goal: To reduce cooling loads.

Best Applied: This is a common approachfor use on low buildings in hot climates.

How to Do It: Use roofing systems withlight-colored or reflective top layers.

Related Strategies: Extended Plan.

Comments: Reflected light may comple-ment other efforts aimed at daylighting“wedding cake”-type building forms.Early in the process, the designer needsto know the color of any roofing systemsthat will be visible to building occupants.

Fabric Roofs

Description: These are tension roofs con-structed of stretched, light-transmittingfabric—an increasingly popular archi-tectural element.

Goals: Provides a buffer from directexposure to solar heat gains occasionedby daylighting of space.

Best Applied: Deploy fabric roofs overlarge, clear-span spaces.

How to Do It: The overall approach mustbe decided early in the design process.Before committing to the design, care-fully evaluate the balance between light-ing, cooling, and heating loads for thespecific building use and climate.

Related Strategies: Extended Plan; Atrium.

Comments: Fabric roofs are useful astemporary or permanent coverings over outdoor spaces (i.e., tents). Theyhave been effectively used at the DenverInternational Airport and the San DiegoConvention Center.

Design Development I Phase

During the earlier phases of the project,basic decisions are made that affect building massing and determine whichlow-energy design strategies will be implemented. During those phases, theoverall thrust is to reduce the heatingand cooling loads as much as possible.During design development, the designteam’s attention should shift to identify-ing efficient lighting and HVAC systems.

Action Item

• Continue energy analysis and the“trade-off” process.

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A skylighted entryway that also demonstrates the integration of photovoltaics at the ThoreauCenter for Sustainability at Presidio National Park, California.

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Denver International Airport in Denver,Colorado, is an example of a fabric-covered roof.

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Strategies to Consider During this Phase

Energy-Efficient Lamps and Ballasts

Description: Identifying and using appli-cation-specific, high-efficiency lampsand ballasts.

Goal: Minimize the amount of electricalpower required by lighting systems,while still meeting the task-specificneeds of building occupants.

Best Applied: The savings will be greatestin buildings with long hours of occupancyor in areas with high electrical utility rates.

How to Do It: Use T-8 (tubular, 8/8th ofone inch in diameter) lamps and com-patible electronic ballasts for generalambient lighting. Compact fluorescentlamps should replace incandescent orhalogen lamps in downlights, as theyonly use about one-third the electricalpower. Determine what lamp/ballastcombinations work best with otherstrategies (i.e., daylighting, shading,lighting controls). Use light-emittingdiode (LED) exit lights with an estimatedlife of 30 years or more to enhance build-ing safety and all but eliminate requiredmaintenance.

Related Strategies: All daylight-relatedstrategies.

Comments: The color rendition of all fluo-rescent lamps has improved dramatically

in recent years, to the point where theyare now deemed acceptable for mostapplications. Compact fluorescent lampsalso provide maintenance savings, as thelamps last 10 to 20 times longer than theincandescents they replace.

Lighting Controls

Description: Lighting controls automati-cally adjust lighting levels in response to daylight availability. Other controlsautomatically turn lights off in responseto unoccupied space.

Goal: This strategy significantly reduceslighting-based electricity demand.

Best Applied: Dimming controls are usedin conjunction with building designsthat encourage entry of natural daylight.Occupancy sensors are best used inspaces that have intermittent occupancy,such as conference rooms and storageareas.

How to Do It: Automatic daylight dim-ming controls either provide light levels in discrete steps or through continuousdimming, based on light levels sensed.

Dimming systems can also be used to dimnewly installed lamps when their lightoutput is greater than it will be once they“burn in”and achieve their rated output.

Occupancy sensors are used to turn offlights and sometimes HVAC in unoccu-pied areas. They are made with multiple

activation technologies, including thosethat sense body heat (infrared) as well asthose that detect motion (ultrasound).Some sensors employ more than onetechnology as a means of eliminatingfalse signals. Manual switching andtimeclocks can also be used to controlcertain daylit spaces.

Related Strategies: HVAC Controls

Comments: Automatic lighting controlfunctions are often included in a com-puterized energy management systemthat also controls the HVAC, fire safety,and security systems.

High-Efficiency Heating, Ventilation,and Cooling Equipment

Description: This category of equipmentoffers operating efficiencies far greaterthan those afforded by systems designedto simply meet applicable codes or standards.

Goal: Integrate more efficient equipmentwhenever it can be shown to be costeffective.

Best Applied: These systems are appro-priate for use with large loads, longoperating hours, and high energy prices(particularly for electricity).

How to Do It: There are various types ofefficient heating and cooling equipmentthat can readily address the specificneeds and operating patterns of a givenbuilding. Many agencies require thatalternate systems be subjected to a life-cycle cost analysis. If such an exercise isconducted, it should involve detailedcomputer analysis (such as DOE 2.2)rather than a process that simply con-firms the selection of a preferred system.Ask the design team to prepare a list of performance criteria for equipmentrequired by applicable codes and stan-dards to be used as a basis for compar-ing more efficient equipment options. In some cases, the cost premium for more efficient equipment is small andcan be justified by hand calculations.More often, DOE 2.2 computer analysesare required along with some form of rigorous life-cycle cost analysis.Consider using modular equipment(e.g., three small boilers instead of one

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Some examples of energy-efficient lamps.

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large one or a dual compressor chiller)and variable-speed equipment (modu-lating burner or variable-speed chiller)for greater flexibility in achieving tar-geted reductions in energy use.

Related Strategies: All design decisionsthat affect heating and cooling loads.

Comments: Specifying systems that arelarger than necessary can be costly. Theenergy consultant should be carefulthroughout the design process to sizethe systems, components, and equip-ment appropriately. HVAC systemsshould also be designed to ensurehealthful indoor air quality in a mannerappropriate to individual spaces and the overall building type.

Exhaust Air Heat Recovery

Description: This process involves therecovery of useful heat from the airbeing dispelled from a building.

Goal: Transfer 50% to 70% of the heatthat would otherwise be lost to theincoming air stream.

Best Applied: Apply this strategy inbuildings with large populations or sig-nificant ventilation requirements, partic-ularly those located in cold climates.

How to Do It: Various types of heatexchangers are in use today, including

heat wheels, plate and fin air-to-air heatexchangers, and heat pipes. Heat pipesare very simple devices that consist of ahighly conductive tube filled with refrig-erant which, when vaporized, transfersheat from the outgoing to the incomingair stream. Because heat exchangersobstruct the air passage of both intakeand exhaust ducts, bypass dampersshould be installed to facilitate operationduring mild or warm weather.

Related Strategies: HVAC controls

Comments: Depending on the application,potential contamination of the incomingair stream may need to be monitored.For instance, recovery of heat from acombustion process is usually accom-panied by a carbon monoxide sensorlocated in the intake.

Economizer Cycle Ventilation

Description: Contributing to both energyreduction and good indoor air quality,this strategy introduces a varyingamount of ventilation air to cool thebuilding in combination with normal air conditioning (AC).

Goal: Avoid using the AC compressorsor other mechanical cooling methodwhen ambient air can provide some or all of the needed cooling.

Best Applied: Look to buildings in coolclimates where there is low relativehumidity.

How to Do It: Provide appropriate con-trols, along with 100% outside-air capa-bility. Consider including enthalpy (total heat, sensible plus latent) controls to maximize benefits.

Related Strategies: Induced Ventilation;Natural Ventilation through Windows;Nighttime Cooling Ventilation.

Comments: This should be considered astandard low-energy HVAC procedurein all but the most humid climates.

Nighttime Cooling Ventilation

Description: High-volume, fan-poweredventilation of large areas during cool,dry nights.

Goal: Cool the building (particularlyexposed massive structural elements)with outside air as a means of savingmore AC power than the sum of thepower drawn by the ventilating fan,plus what is needed to overcome anyexcessive humidity the following day.

Best Applied: This strategy is appropriatefor hot, dry climates where the diurnaltemperature difference (between dayand night) often exceeds 30°F to 35°F.

How to Do It: This strategy relies on mov-ing large quantities of air in an econom-ical manner and requires a secure sourceof intake ventilation that can be directedinto spaces to be cooled.

Related Strategies: Natural Ventilationthrough Windows; Economizer CycleVentilation

Comments: Large amounts of interiormass enhance the cooling effect in dryclimates that consistently experience significant temperature swings. In vari-able climates, lower mass is desirable.Relying on open windows for ventila-tion (in lieu of forced-air fan operation)may compromise security or lead towind or water damage.

HVAC Controls

Description: Specify controls that main-tain intended design conditions, includ-ing temperature, humidity, and airflow

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The Louis Stokes Laboratory at the National Institute of Health in Bethesda, Maryland, isusing desiccant heat wheels for exhaust air heat recovery.

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rate in terms of cubic feet per minute(cfm) throughout the building.

Goal: The proper use of controls andbuilding automation reduces energyconsumption and electrical peakdemand.

Best Applied: In all circumstances, strivefor a level of functional complexity thatis compatible with the skills and capabili-ties of the building’s operating personnel.

How to Do It: Keep control systems assimple as possible. Avoid controls thatoffer little in the way of improved opera-tions or energy savings, especially ifthey complicate the system and add features that require frequent mainte-nance or are subject to malfunction.Evaluate the use of variable-speed drives (VSD) on all large pumps andfans serving loads that only occasion-ally function at peak capacity. In large spaces with varying occupancies (auditoriums, large meeting rooms, cafeterias), investigate control strategies(e.g., the use of carbon dioxide monitors)that regulate the amount of outside airin accordance with actual occupancy.Consider using setback thermostats inall building types. However, avoid set-ting temperatures back in spaces wherea large amount of exposed thermal masswill make it difficult to reestablish com-fortable temperatures.

Related Strategies: Lighting Controls

Comments: HVAC control systems canoften be integrated into computerizedsystems that also control lighting, firesafety, and security.

Value Engineering (VE) Phase

Action Items

• Ensure that VE analysis is based onlife-cycle considerations rather thansolely on cutting initial constructioncosts.

• Incorporate energy analysis directlyinto the VE process.

• Be certain that energy targets for thefacility are maintained during VE.

• Meet the needs of the building occu-pants and the intended use throughdesign that is consistent with agency or organizational values and mission.

Design Development II Phase

Action Items

• Continue energy analysis as design isfinalized to ensure that desired energyperformance objectives are maintained.

• Review final working drawings, specs,and cost estimates.

Construction Documents Phase

Action Items

• Ensure that construction details andspecifications are consistent with energyuse targets and strategies.

• Be sure that mechanical system detailsand equipment sizing meet design targets.

• Reaffirm that lighting system detailsand equipment specifications are consistent with energy design intent.

• Before documents are sent out for bid,conduct a final energy design review.

Bid Solicitation/Contract Award Phase

Action Items

• If cutting costs is required due to highbids, advocate preserving vital energy-saving features in lieu of more easilyreplaceable or aesthetic components.

• Conduct additional energy analyses asnecessary to ensure that intended energyperformance targets are still intact.

Construction Phase

Action Item

• Ensure that energy features are con-structed or installed as designed.

Turn Over to Occupants Phase

Action Item

• Verify that occupants understand thebuilding systems and the proper use oflow-energy equipment and features ofthe building.

Warranty Period/Commissioning Phase

Action Items

• Verify occupant comfort and under-standing of building operation using aPost Occupancy Evaluation (POE).

• Monitor the energy performance of thefacility once per quarter during the war-ranty period and fine-tune the system asneeded.

• If feasible, develop and implement afull commissioning protocol.

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This building incorporates many features that lessen its impact on the environment.

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What to AvoidSome low-energy buildings fail to meetthe expected energy savings because theenergy-efficient technologies incorpo-rated into the design are not correctlyintegrated into the building. This maybe due to a lack of understanding on the part of some team members as to the relationships between the specificenergy technologies needed to reduce a given building’s energy use and theeffective integration of these technolo-gies into the design. Changing just oneof the recommended building compo-nents changes the total environmentand, thus, the effectiveness of the remain-ing technologies. To avoid this, it is cru-cial that all team members understandhow each of the technologies interactswith all other building components in a given environment.

When choosing energy-saving technolo-gies, team members should be skepticalof claims for unrealistically high levelsof performance and should avoid depen-dence on proprietary devices. It is notadvisable to have a design that relies ona particular technology for which onlyone product is available. In those fewcases where the use of such proprietaryproducts can be defended in the contextof competitive bidding requirements, acontingency design strategy should bein place. Claims of high-level perform-ance should be supported by objectivetests and case study results.

Design Considerations andComputer ModelingThe Base Case

A base-case design—a code-compliantbuilding design without low-energydesign features—is needed for compari-son purposes in analyzing the cost andeffectiveness of the low-energy designstrategies identified for consideration.Considerations other than low-energydesign often dictate the basic design of a building. In these instances, the base-case building is automatically createdthrough the normal design process. Tobe effective, some low-energy buildingdesign technologies need to be appliedduring the early stages of the project,

such as authorization, site selection,budgeting, and programming. In theseinstances, the base-case building mayalready include some low-energy design features.

For example, an atrium is a desirableamenity that, if incorporated early in the project, should influence decisionsabout site selection, building orientationon the site, and the number of buildingsrequired to satisfy the space needs of thefacility. But if the atrium is introducedafter the overall building configurationis set, the parallel use of the atrium as alow-energy design component will becompromised, and it may end up beingan energy liability. Similarly, in climateswhere a campus plan yields energy ben-efits, these benefits can be includedamong the criteria used to define thebasic site plan—especially if introducedin the early project stages.

Anticipating low-energy design strategiesearly in the project can also influence thechoice of a base case. One attraction ofmany low-energy building design strat-egies is that the occupants gain a closerconnection with the outdoors environ-ment. If this attraction is part of thedesign program, low-energy buildingdesign strategies may become more eco-nomical relative to the base-case design.For example, if the maximum allowabledistance between any office worker and a source of natural light is lowered fromthe 60 feet typically accepted in a stan-dard office buildings to 30 feet, a linearatrium between two 60-foot-wide build-ing segments may result in a moreattractive, compact, and, therefore,potentially more economical, designwhen compared to a 60-foot-wide base-case building.

Strategy InteractionsAn important low-energy designapproach involves rank-ordering a listof candidate technologies. At each stepin a series of computer-driven energysimulations, candidate strategies areranked in order of cost effectiveness relative to the base-case design. The top-ranked strategy would be the onethat yields the largest energy savings for the smallest investment—the one

with the shortest simple payback. [Note: according to the U.S. Departmentof Energy’s (DOE’s) A Guide to MakingEnergy-Smart Purchases, the simple payback period is the amount of timerequired for the investment to pay foritself in energy savings. You can obtainan estimate of the simple payback periodby dividing the total cost of the productby the yearly energy savings. For exam-ple, an energy-efficient dryer that costs$500 and saves $100 per year in energycosts has a simple payback period of 5 years.]

As each strategy is applied, the paybackfor all subsequent candidates maychange. Because there is less energy tobe saved, the savings potential is oftenreduced. If all the strategies were inde-pendent, the remaining ones wouldretain their order in the ranking as eachis applied in succession. In practice,however, low-energy building designstrategies do interact and change theirrelative order in the ranking as they areapplied. Presuming that the initial rank-ing will remain constant can lead to mis-judgments about which strategies topursue. After applying each strategy in a simulation, re-rank the remaining candidate strategies. Designing Low-Energy Buildings with ENERGY-10 can perform this task automatically (see Design Tools).

Another example of the interaction amongbuilding elements is in an office buildingwhere natural lighting displaces electricalenergy by reducing the use of auxiliarylighting. In this case, the need for auxil-iary heating increases in cold weather inresponse to the reduced heat contribu-tion previously supplied by electricallighting that is now dimmed or turnedoff. If this effect is not taken into accountin the simulation, exaggerated estimatesof energy savings will occur. Finally, it isimportant to remember that using onetechnology may preclude using certainothers. For example, in buildings whereheating or cooling loads have been sig-nificantly reduced, the benefits of usinghigh-efficiency equipment to meet thoseloads may also be reduced and theresulting simple paybacks lengthened.

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The Benefits of Multiple UseAs previously noted, BIPV—integratingPV into the building envelope—canreplace conventional building envelopematerials and their associated costs. PVis a solid-state, semiconductor-basedtechnology that converts light energydirectly into electricity. For example,spandrel glass, skylights, or roofingmaterials might be replaced with archi-tecturally equivalent PV modules thatserve the dual function of building skinand power generator. By avoiding thecost of conventional materials, the incre-mental cost of PV is reduced and its life-cycle cost is improved. BIPV systems caneither be tied to the available utility gridor they may be designed as stand-alone,off-grid systems. One of the benefits ofgrid-tied BIPV systems is that on-siteproduction of power is typically greatestat or near the time of a building’s peakloads. This provides energy cost savingsthrough peak load shaving and demand-side management capabilities.

MaintenanceA well-designed, low-energy buildingrequires less maintenance than one thatrelies on large mechanical systems.Unlike other technologies, well-inte-grated low-energy building design ismuch less dependent on hardware andequipment, so there is little to go wrong.The traditional building trades that useavailable construction materials are ableto make repairs as needed. The reliabilityand performance record of other technol-ogies (such as movable shading devices)should be investigated, and whendeployed, moving parts should be regu-larly maintained. Cleaning and protect-ing the surface of shading devices andglazing is important and should beincorporated as part of ongoing, scheduled maintenance.

When properly implemented, low-energybuilding design can reduce heating andcooling loads to allow for equipmentdownsizes and reductions in mainte-nance costs. Ideally, it also yields abuilding that can continue to functionon a basic level and remain habitableeven when systems experience unex-pected downtime.

CostsCost effectiveness is typically the primarycriterion for evaluating low-energy build-ing technologies. 10 CFR 435 and Execu-tive Order 13123 require that energy-related design decisions be evaluated ona life-cycle basis, rather than simply on a first-cost basis (e.g., construction costs)alone. It should be noted that the higherfirst costs of low-energy design can oftenbe avoided or greatly minimized byanticipating and incorporating thesestrategies at the outset of the planningprocess. Exceptions might include:

• Demonstration projects with supple-mental funds specifically earmarked for technology promotion.

• High-profile projects where publicityvalue adds to the payback.

• Cases where it is impractical to estab-lish cost effectiveness. For example, rela-tively small investments that cannotjustify a detailed simulation and seempractical based on prior experience.

• The amenity value of the technologyoutweighs its energy performance. Caremust be taken to ensure that the amenitydoes not increase energy demand.

Typically, a building’s cost effectivenessshould be measured using appropriatedesign and analysis tools, such as thosedescribed below. As previously noted,different forms of energy have differentcosts, with electricity costs approximatelythree times that of natural gas. Becausethe costs of various energy sources varygreatly by region, specific input isrequired in each case.

Except for residences, utility cost data isnot simply a matter of cents per kilo-watt-hour of electricity, or dollars pertherm of gas. Especially in larger build-ings, the various fixed costs, variablecosts, step rates, and demand chargesmust be accurately calculated. It issometimes appropriate to run separatesimulations, with and without demandrates, to see the extent to which the sav-ings offered by a low-energy feature isdependent on demand rates. Small-scaleco-generation may also be evaluatedalong with other energy sources appro-priate for larger projects.

To accurately model these costs, the moresophisticated design tools (such as DOE 2.2) accept all the details of utilityrate structure, whereas simpler tools rely on a simplification of the rates. It isimportant to realize, however, that sim-plified rates may mask a large demandcomponent and can be very misleading.It is also worth noting that when neces-sary energy-efficient technologies arewell balanced and function in a comple-mentary manner, they will significantlyreduce energy consumption during peak load periods.

This guidebook does not discuss utilityrates, assuming that one of the final cal-culations made in evaluating a giventechnology involves using actual, proj-ect-specific utility rates to determine the anticipated savings. Team memberswith experience in using a given tech-nology in a particular locality can oftenpredict probable outcomes based ontheir knowledge of the interactionbetween the climate and utility costs.For example, measures affecting elec-trical consumption (such as fan energyor reduced lighting demand) will have a better payback in New England, where electricity costs are high, than in the Northwest, where lower-costhydropower is available.

Financing Options

Energy savings performance contracting(ESPC) arrangements are a relativelynew method of helping Federal agenciesinvest in energy-efficient building meas-ures. ESPC is a contracting agreementthat enables agencies to implement ener-gy-saving projects without making cost-ly up-front investments. The contractoror other partner, such as a utility, ownsthe energy system and incurs all costs—design, installation, testing, operations,and maintenance—in exchange for ashare of any energy cost savings realized.

FEMP provides ESPC and utility financ-ing workshops, model solicitations, anda how-to manual. For more information,call FEMP at 703-243-8343. You may alsowish to contact the Energy Efficiencyand Renewable Energy Clearinghouse at 800-363-3732, or check their Web site at www.eren.doe.gov/femp.

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Design and Analysis ToolsTypically, a building’s cost-effectivenessneeds to be measured using an appro-priate design and analysis tool, such as those described below.

ADELINE (includes SUPERLITE andRADIANCE): A software tool for day-lighting design that links daylightingand thermal performance. Availablefrom Lawrence Berkeley NationalLaboratory, 510-486-4000.

BLAST: A detailed, annual energy per-formance software tool capable of mod-eling the interactive effects of low-energy building design strategies suchas daylighting, passive solar heating,and thermal mass. Available from theBLAST Support Office, 217-333-3977.

BLCC: A software tool to calculate lifecycle cost according to federal criteria.See http://www. eren.doe.gov/buildings/tools_directory/software/blcc.htm

CFD: An abbreviation for “computerizedfluid dynamics,” this highly sophisticatedtype of program can track the flow of airwithin a space or building componentand determine the temperature distribu-tion within that space during systemoperation. It requires considerable expe-rience to operate, but is invaluable forassessing the effectiveness of air dif-fusers. Available from several vendorsunder several names. See http://www.eren.doe.gov/buildings/tools_directory

DOE 2/DOE 2.2: An energy analysissoftware program that calculates thehour-by-hour energy use of a building,given detailed information on the build-ing’s location, construction, operation,and HVAC systems. Available fromLawrence Berkeley National Laboratory,510-486-4000.

Designing Low-Energy Buildings WithENERGY-10: An hour-by-hour, annualsimulation program designed to analyzeresidential and commercial buildings ofless than approximately 10,000 squarefeet (one or two zones). Specifically con-ceived for use during the earliest phasesof design when low-energy buildingstrategies can be incorporated at thelowest possible cost. Available from the

Sustainable Buildings Industry Council(SBIC), 202-628-7400, ext. 209.

FRAME: A powerful thermal analysisprogram that accurately tracks the flowof heat through assemblies. A basic toolfor analyzing thermal bridging throughfaçade elements, such as windowframes. Requires some experience foroptimum use. See http://www.eren. doe.gov/buildings/tools_directory/software/framepls.htm

POWERDOE: Windows-based versionof DOE 2 with user-friendly interface.Available from Fred Winkleman, 510-486-4925.

SERI-RES: (also SUNREL, which is anupgraded version of SERI-RES that fea-tures enhanced algorithms): Analyzespassive solar design and thermal per-formance in residential and small com-mercial buildings. Available from RonJudkoff, National Renewable EnergyLaboratory (NREL), 303-275-3000.

TRNSYS: Modular FORTRAN-basedtransient simulation code that allowssimulation of any thermal energy sys-tem, particularly solar thermal, building,and HVAC systems. Available from theSolar Energy Laboratory, University ofWisconsin, TRNSYS Coordinator, 608-263-1589

Energy SavingsEnergy savings will vary, depending onclimate, building type, and strategiesselected. In new office buildings, it iseconomically realistic to reduce energy costs by 30% or more below nationalaverages if an optimum mix of low-energy design strategies is applied.According to the Building Owners andManagers Association (BOMA), theaverage energy cost (taking into accountindicative samples of both public andprivate buildings) is $1.85 per rentablesquare foot. As previously noted, theFederal government maintains approxi-mately 2.9 billion square feet of rentablespace. Thus, a 30% reduction in energyuse would yield annual taxpayer sav-ings of 55.5¢ per square foot, or a $1.6billion reduction in the nation’s annualenergy bill. This figure does not take into account the additional savings

realized through pollution prevention,resource conservation, and related cost-reduction measures. Although a 30%reduction may seem ambitious, build-ings monitored by NREL’s Low-EnergyBuilding Program show energy con-sumption reductions as high as 75% inresidential buildings and 70% in somenon-residential buildings.

Other ImpactsBetter design techniques and superiortechnologies have largely eliminatedany negative impacts associated withlow-energy building design, such asoverheating due to uncontrolled solargain. The environmental benefits of low-energy building design can be sig-nificant, depending on how many ener-gy-efficient or sustainable products areused. For example, a building that incor-porates green materials (such as paintswith low or no volatile organic com-pounds [VOCs] and recycled buildingmaterials) has less of an impact on natu-ral resources than does a conventionalbuilding. HVAC systems that use non-chlorofluorocarbon (CFC) refrigerantsare less harmful to the earth’s ozonelayer, and passive solar buildings thatuse significantly less energy from fossilfuels contribute less to the greenhousegas effect than conventional buildings.Taken together, these low-energy, sus-tainable buildings not only reduce theburden on American taxpayers, but alsocontribute to the health, well-being, andproductivity of their occupants.

Case Studies

The United States Courthouse Expansion,Denver, Colorado

The United States Courthouse expansionin Denver, Colorado, consists of 17 newcourtrooms and associated supportspaces, totaling 383,000 square feet. TheGeneral Services Administration (GSA)designed this project to serve as a show-case for sustainable design and devotedconsiderable attention to the building’senergy and environmental design fea-tures. Sustainable design strategies integrated into the building include:

• High-performance glazing system

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• Daylighting complemented by energy-efficient electric lighting

• Energy-efficient HVAC systems andcontrols (e.g., displacement ventilationand evaporative cooling)

• Building-integrated photovoltaic system

• Recycled and low-VOC materials usedthroughout

• Integrated building automation system

• Low-impact landscaping

• Water-saving faucets and toilets.

Based on computer analysis using DOE 2.2, the building is expected to consume approximately 50% less energy than a minimally compliantbuilding designed in conformance withthe Federal Energy Standard 10 CFR 435.As such, its annual energy costs will bereduced from just under $300,000 peryear to just over $150,000. Much of theenergy savings achieved in the DenverCourthouse expansion will be the resultof reduced energy demand associatedwith lighting, heating, and cooling.

Beyond its energy- and resource-efficientdesign features, the building will also provide an improved indoor environ-ment that is expected to increase work-place performance while improving staff health, safety, and satisfaction.

In keeping with its sustainable designapproach, the Denver Courthouseexpansion will also reduce operationsand maintenance costs and will rely, inpart, on non-polluting renewable energysources. Descriptions of the facility’sspecific low-energy, high-performancefeatures follow.

High-Performance Glazing

Taking full advantage of Denver’s sunny,dry climate, a high-performance, triple-glazed curtain wall system is used onthe court tower to minimize HVAC heat-ing and cooling loads, while affordingdramatic views and a source of naturallight for adjacent courtroom and confer-ence spaces. A series of PV cells are inte-grated into the curtain wall system, pro-viding a clean, renewable source ofpower, as well as a visible representa-tion of the government’s commitment to climate-responsive, sustainable architecture.

Daylighting

The daylighting design for the DenverCourthouse expansion is based on a conscious separation of view glass fromdaylighting-specific glass. The systemprovides for maximum daylight har-vesting and usage to reduce electriclighting loads during the day, as well asoccupant satisfaction based on a strongsense of connection with the outdoors.

Perimeter light shelves are incorporatedthroughout the high-rise section of thebuilding and are positioned at the junc-tion between the view and the daylightglazing. The shelves diffuse daylightonto the ceiling plane and adjacent sur-faces, thus minimizing contrast ratiosbetween interior surfaces and elementsviewed through the glazing. This, inturn, serves to increase visual comfortand improves the quality of the view to the outside.

Energy-Efficient Electric Lighting

The facility’s artificial lighting system isdesigned to supplement daylight andwill use a combination of direct andindirect luminaries with T-5 fluorescentlamps and dimmable electronic ballasts,together with compact fluorescent andmetal halide downlights and wall washers. Illumination levels aredesigned to work in tandem with day-lighting and high-performance glazingsystems to provide a balanced luminousenvironment with low energy consump-tion. Photocell controls will be used inconjunction with electronic fluorescent dimming ballasts to save energy in areas receiving daylight, while low-level ambient lighting enhanced byoccupant-controlled task lighting willilluminate areas not served by daylight-ing. Occupancy sensors will controllighting in private offices.

Displacement Ventilation

The ventilation systems that serve thecourtrooms, various offices, and publiccorridor spaces incorporate displace-ment ventilation air distribution. Thissystem features low-velocity air intro-duced at floor level to efficiently condi-tion the space and remove indoor airpollutants.

Evaporative Cooling System

Much of the building’s cooling andhumidification loads are met using anindirect and direct evaporative coolingsystem, which provides a cooling effectthrough water evaporation. This processgreatly reduces the need to run an elec-tric-powered chiller. Denver’s dry cli-mate makes this system ideal for much

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The U.S. Courthouse Expansion in Denver, Colorado, will be a showcase for sustainablebuilding design.

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of the cooling season; indeed, computersimulations show less than 100 full loadhours of chiller operation per year. Thesystem is also used to add humidity tothe building during the winter toimprove occupant comfort.

Variable Air Volume Systems (VAV)Using Variable-Speed Drives (VSD)

The heating and cooling needs are fur-ther addressed by a VAV air-handlingsystem, which adjusts supply air vol-umes in response to the heating andcooling needs of the various zones.VSDs are installed on all fans andpumps to reduce the energy consump-tion of these devices during part-loadoperation. The main air handler incor-porates four separate supply fans thatcan be individually staged, allowing for efficient operation of the systemdown to 5% of design air flow. The use of VSDs is especially important incourthouse facilities, due to their vari-able occupancy characteristics and occasional nighttime use.

Building Automation System

A full direct-digital-control system isused to control the HVAC and lightingsystems. The system is designed to shutdown the HVAC and lighting systems inunoccupied spaces and, in tandem withthe VAV air handling and pumping sys-tems, provides efficient operation underpartial occupancy.

Building-Integrated Photovoltaics

PV is integrated into the southeast cur-tain-wall system adjacent to the publiccorridor areas of the tower, and a sky-light is located over the security drumelement in the Special Proceedingspavilion. Translucent, thin-film cells are applied to the skylight and selectedpanels in the curtain wall system, andadditional polycrystalline PV panels areused as spandrel panels in the curtainwall system. The PV panels provideelectricity during sunlight hours, reduc-ing peak electric demand. Battery stor-age is not necessary, because systemoutput is greater than building demand.

Landscaping

A variety of measures can be implementedto optimize the landscape surrounding abuilding. Among these, preservation ofexisting landscape features should bethe designer’s first course of action.Mature trees and vegetation are valu-able resources that take many years toreplace. Preserving them not onlyallows for their use in natural shading(and in some climates, as a wind breakor shelter belt), it also maintains existingwildlife habitats, existing drainage pat-terns, and soil conditions. Tree preserva-tion reduces the need for excavation,transportation, and relocation of soil. In addition, it reduces the need for sup-ply and transportation of fill and land-scape materials. When adding newvegetation to a site, use regionally con-sistent landscaping strategies, composedof locally grown, native plants.

Water Efficiency

One of the most overlooked areas indeveloping a whole-building designstrategy is the efficient use of waterresources. To process and use water, the Federal government expends 59.2 billion Btu of energy on an annualbasis; more than 98% of this energy isused to heat water. Thus, significantenergy and dollar savings can be real-ized by implementing water-efficientmeasures. Water efficiency is theplanned management of water to pre-vent waste, overuse, and exploitation of the resource. Effective water-effi-ciency planning seeks to “do more withless,” without sacrificing comfort or performance. Water-efficiency planning is a relatively new management practicethat involves analyzing cost and waterusage, specifying water-saving solu-tions, installing water-saving measures,and verifying the savings to quantifyresults.

A variety of water conservation technol-ogies and techniques can be used to savewater and associated energy costs,including:

• Water-efficient plumbing fixtures (e.g., ultra-low-flow toilets and urinals,waterless urinals, low-flow and sen-

sored sinks, low-flow showerheads, andwater-efficient dishwashers and wash-ing machines)

• Reducing water use associated withirrigation and landscaping (water-effi-cient irrigation systems, irrigation-con-trol systems, low-flow sprinkler heads,water-efficient scheduling practices, and xeriscaping)

• Graywater and process recycling sys-tems that recycle or reuse water

• Reducing water use in HVAC systems.

Demand-side management methodsreduce the amount of water consumedon-site at a facility and include systemoptimization, water conservation meas-ures, and water reuse and recycling sys-tems. Other efficiency options includeleak detection and repair, industrialprocess improvements, and changingthe way fixtures and equipment areoperated and maintained.

National Renewable Energy Laboratory’sThermal Testing Facility, Golden, Colorado

NREL’s Thermal Testing Facility (TTF) isan open-space laboratory building com-prised of high-bay laboratory areas,offices, and conference rooms. Design of the 10,000-square-foot building began early in 1994, and constructionwas completed in the summer of 1996.Performance monitoring has beenunderway since occupancy. Althoughthe TTF was designed to serve as a laboratory, the technologies discussed in this case study are appropriate to awide range of commercial buildings,offices, warehouses, and institutionalfacilities. Sustainable design strategiesintegrated into the building include:

• Passive solar features

• Efficient electric lighting

• Daylighting features

• Occupancy sensors

• Efficient HVAC design

• Energy management system withdirect digital control (DDC).

The TTF’s design team included an arch-itect, mechanical engineer, electrical

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engineer, structural engineer, building-owner facilities staff, and an energy consultant. From the outset, the teamfocused on optimizing the interactionsamong the building’s various systems,taking into account the influence ofbuilding occupants, their daily activities,and climatic conditions in the surround-ing area. Energy-related design deci-sions were based in part on the results of computer simulations using DOE 2(1994). The building’s owner (U.S. DOE)and eventual occupants (NREL staff)determined necessary building criteriaat the outset of the design phase. Thetype of spaces required included flexiblegeneric laboratory space, assorted open-area support offices, a conference room,washrooms, and a kitchenette area.

Once the building’s use was established,the design team and NREL researchengineers set a building energy costreduction goal of 70%, and a strategicdesign and construction plan was devel-oped to serve as a “road map” to guidethe process. The plan included integrat-ing passive solar features, low building load coefficient, efficient electric lighting,daylighting features, occupancy sensors,efficient HVAC design, and an energymanagement system with DDC.

With a Congressional budget of $1.5 mil-lion to cover all design, construction, andcommissioning costs, a code-compliantbase case was created for the TTF’sdesign, using 10 CFR 435 (1995) as thereference. (The base-case design is a useful benchmark for gauging the rela-tive cost effectiveness of both individualand collective performance improve-ments.) The base case was simulatedusing SERI-RES to study the thermalaspects of the building, and DOE 2.2 for HVAC and lighting studies.

Initial base-case results showed that elec-trical lighting loads accounted for a largeportion of the energy use—roughly 73%,not including plug loads. Cooling loadswere next, at 15% of the building’s totalenergy consumption. Based on thisinformation, the NREL research staffbelieved that internal heat gains couldbe minimized by reducing the electriclighting load and by minimizingunwanted solar gains. This was accom-plished by integrating daylighting andefficient artificial lighting strategies,specifying high-performance windows,and by engineering the dimensions ofoverhangs. By minimizing the coolingload, the design team was also able todownsize the HVAC system in compari-

son to what would have been requiredin the base-case scenario.

Computer modeling indicated that thelargest energy savings could be achievedby reducing the electric lighting load.Reducing plug loads had a similar effect,but plug loads are not related to thebuilding envelope design. Reducinginfiltration, controlling ventilation andunwanted solar gains, and improvingthe building’s opaque envelope all pro-duced similar energy-saving results. In addition, the facility’s interior wasarranged to free up additional floor area.By moving the mechanical room fromthe exterior east wall to a location abovethe central core (where the restrooms,storage, and kitchen areas are located),an additional 800 square feet of labora-tory floor space was created without aconcomitant increase in energy use. TheTTF’s final low-energy design achievedits energy reduction goal by appliedenergy-efficient design strategies asdescribed below.

Passive Solar Design

To take advantage of Colorado’s sunnyclimate, the TTF integrates many passivesolar features, including appropriate siting and building orientation. Thedesign also incorporates a small amountof thermal mass in the slab floor andnorth wall of the building, and the north wall also acts as a retaining wallfor a mesa, providing the thermal bene-fits of earth berming. Among the facili-ty’s most important features, however,are the proper selection, orientation, and placement of windows and clerestories.

The building was carefully engineeredto provide passive solar gain in the win-ter months, while minimizing this gainduring the summer. The final designincorporates 88% of its total fenestrationas a single row of view glass and tworows of clerestories along the southernfaçade. An additional 8% of view glass is divided equally between the east andwest façades, while the remaining 4% ispositioned on the north wall. South-fac-ing clerestory windows were designedwith a high SC of 0.76 (SHGC of 0.68),

34

The National Renewable Energy Laboratory’s Thermal Testing Facility shows how sustainabledesign strategies can be integrated into a variety of commercial buildings, offices, warehouses,and institutional facilities.

War

ren

Gre

tz/P

IX04

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while all others have a lower SC of 0.51(SHGC of 0.45). The higher SCs allowmore solar gain to enter the building. In addition, all windows have a low-ecoating, which prevents the transmis-sion of most non-visible spectrum lightand unwanted solar gain. The carefuldesign and placement of overhangsrounds out the picture by blocking direct solar radiation during the sum-mer when sun angles are high, whileallowing direct solar radiation in winter,when sun angles are much lower.

Overall, the TTF’s envelope and its pas-sive solar features were designed to heatthe building during the day and into theevening hours, such that the only heatload on the building will take place during the morning hours. Bear in mindthat the glazing configurations and otherpassive solar strategies described aboveare very much site- and application-specific and will not necessarily applyto different building types in other locales.

Thermal Envelope

The TTF’s floor is constructed of a 6-inchconcrete slab with 4-foot perimeter insu-lation. The north wall is constructed ofan 8-inch concrete slab with 2 inches ofrigid polystyrene, while the east, west,and south walls use 6-inch steel studswith batt insulation positioned betweenthe studs. Expanded polystyrene isplaced over the entire exterior surface,which is finished with Exterior Insu-lation and Finish System (EIFS) stucco.The roof is constructed using metaldecking atop steel supports with a 3-inch polyisocianurate covering. Thethermal insulation positioned on thewall exterior creates an energy sinkwithin the building, which dampens thebuilding’s natural temperature swings.For example, during cold winter nights,when outdoor temperatures drop wellbelow freezing, the TTF’s indoor tem-perature drops by only 10ºF.

Lighting

The TTF is illuminated by a dynamiccombination of electric lighting and daylighting, depending on real-timeoccupancy status and daylight lumi-nance values. A stair-stepped design

is integral to the daylighting plan; day-light enters the building through a rowof view glass and two additional rows of clerestories lining the south façades of the open office areas, mid-bays, andhigh-bays, respectively. Additional windows exist along the east, west, and north walls to balance incomingdaylight. Again, all windows are engi-neered to take full advantage of day-lighting opportunities.

A sensor that measures illumination levelscontrols the building’s supplementalelectric lighting system, and the build-ing’s energy management system (EMS)uses this information to control electriclighting status, depending on the amountof natural light available in each lightingzone. In terms of lighting systems, thefacility uses T-8 and compact fluorescentlighting, 72% of which provides supple-mental lighting to daylit zones, whilethe remaining 28% provides primarylighting to the building’s central core.The EMS-integrated occupancy controlprotocol uses passive infrared and ultra-sonic occupancy sensors to disengagelighting when not required. Together,these features have significantly reducedthe building’s (lighting-based) electricaluse as well as its cooling load, whileheating loads increased only slightlyduring the winter months.

Heating, Ventilation, and AirConditioning

Because the TTF minimizes HVACrequirements, a smaller, more efficient,and less expensive HVAC system wasinstalled. Actually, the TTF uses two separate HVAC systems: a VAV air handling unit (AHU) to serve the mainbuilding, and a packaged single-zoneAHU to serve the conference room. The VAV unit relies on direct and indi-rect evaporative cooling as its primarycooling source, supplemented by ceilingfans, which help reduce the temperaturestratification that is common in spaceswith large ceiling heights.

The TTF’s efficient HVAC design limitedthe total amount of ductwork through-out the building, which, in turn, reducesmaterial costs during construction, aswell as maintenance thereafter. All duct-

work is insulated and located indoors to reduce losses to the outside environ-ment and bordering zones.

Energy Management System

The TTF uses a digital building controlsystem for most mechanical buildingoperations. This EMS allows for easymonitoring, tuning, and diagnosis, helping to keep the building operatingas designed. The EMS operates each ofthe HVAC units and the electrical light-ing system and also collects diagnosticand performance data. Two tanklessheat-on-demand water heaters providethe facility with domestic hot water(DHW): one serving the kitchen and theother dedicated to the washrooms. Bothunits are natural gas-fired and provide80% thermal efficiency.

The Technology inPerspectiveTechnology DevelopmentSince ancient times, people have designedbuildings for the local climate, takingadvantage of natural daylight and pre-vailing winds. Today, these same princi-ples apply to low-energy buildingdesign but are combined with what wehave learned about energy conservation;advanced materials, products, andmechanical systems; renewable energy;and energy performance design tools.When designed in tandem, technologyclusters, such as energy-efficient lighting,occupancy sensors, and daylightingstrategies, can reduce a building’s energyload and improve occupant comfort.

Federal energy managers can be assuredthat sound, climate-responsive designwill yield long-term energy savingsregardless of fluctuations in energyprices and will serve as the basis fordurable, comfortable, environmentallysound buildings. Advances in other keytechnologies will further transform thebuilding industry. New design andanalysis tools have greatly improved the designer’s ability to predict buildingenergy performance, while giving ener-gy managers better control over opera-tions and maintenance costs. As thesetools continue to be refined and their

35


use becomes more commonplace, low-energy building design will emerge asthe only logical approach to new con-struction and renovation.

Technology OutlookThe technologies, systems, and designstrategies discussed in this guidebookare helping to ensure a bright future forlow-energy buildings. As consumerscontinue to demand more sustainabledevelopment and wise environmentalstewardship from their elected leaders,the Federal government is uniquelypositioned to take the lead in making its own buildings as energy efficient as possible, and at the same time making them more comfortable andattractive than their conventional coun-terparts. It is likely, however, that insti-tutional barriers (e.g., restrictive codes,procedures, budget processes) will haveto be revised or removed before the Fed-eral sector can fully meet this challenge.

This guidebook is a tangible step towardachieving more widespread use of whole-building energy design and analysisbecause it makes the process more com-prehensible for all project team mem-bers. There is also an important role forthose who develop new Federal guide-lines and requirements that encouragethe use of low energy and renewableenergy strategies. Though often unsung,these individuals are laying the corner-stone for meaningful, enduring change.

When starting your next project, remem-ber that an accurate assessment of low-energy design features and technologiescomes from a clear understanding—notjust of how the many components of abuilding work—but of how they worktogether. This often begins with anawareness that the current, highly frag-mented building process is not produc-ing the best results, and that a new viewof the building as a system of interde-pendent components is required.

Product ResourcesA vast array of products for low-energybuildings are available from suppliers of traditional building materials as wellas from manufacturers of specialized

technologies, such as PV systems.Because passive solar buildings aredesign intensive, it also is useful toknow how to locate design professionalswith special expertise in low-energybuilding design. For information onproducts and professional services,please refer to the following resources,as well as building product suppliers.

Air-Conditioning and RefrigerationInstituteArlington, VirginiaPhone: 703-524-8800, 800-AT-ARIESWeb site: http://www.ari.com

American Institute of ArchitectsCommittee on the EnvironmentWashington, D.C.Phone: 202-626-7515Web site: http://www.e-architect.com

Architects’ First Source for ProductsWeb site: http://www.afsonl.com

APA—The Engineered WoodAssociationTacoma, WashingtonPhone: 206-565-6600Web site: http://www.apawood.org

Association of Home ApplianceManufacturersChicago, IllinoisPhone: 312-984-5800

Building Design Assistance CenterFlorida Solar Energy CenterE-mail: [email protected] site: http://www.fsec.ucf.edu/~bdac/Manufactures and supplies controls (i.e.,dimming systems, motion/occupancysensors, power reducers, switching sys-tems), energy management systems,glazing (e.g., glass, windows, windowfilms, skylights), insulation systems andradiant barriers, lighting (e.g., energyefficient ballasts, lamps, luminaries, exitlighting, specular reflectors), and roof-ing (e.g., energy-efficient reflective coat-ings, paints, tiles, shingles).

Center for Renewable Energy andSustainable Technology (CREST)Web site: http://www.crest.org

Gas Appliance Manufacturers AssociationArlington, VirginiaPhone: 703-525-9565

Greening Federal Facilities: An Energy,Environmental, and Economic ResourceGuide for Federal Facility Managers(1997). U.S. DOE/FEMPPhone: 800-DOE-ERECWeb site: http://www.eren.doe.gov/ femp/techassist/greening.html

Primary Glass Manufacturers CouncilTopeka, KansasPhone: 785-271-0208

Structural Insulated Panel AssociationPhone: 253-858-SIPA (7472)Web site: http://www.sips.org

Sustainable Buildings Industry Council(formerly Passive Solar IndustriesCouncil)Washington, D.C.Phone: 202-628-7400E-mail: [email protected] site: http://www.sbicouncil.org

Sustainable Building SourcebookGreen Building ProgramAustin, TexasWeb site: http://www.greenbuilder. com/sourcebook

Sustainable Building Technical Manual:Green Building Design, Construction andOperations (1996). Public Technology, Inc.U.S. Green Building CouncilU.S. DOE/U.S. EPA.U.S. Green Building CouncilSan Francisco, CaliforniaPhone: 415-543-3001E-mail: [email protected] site: http://www.usgbc.org

Who is Using the TechnologyThousands of low-energy buildings andhomes have been constructed through-out the United States, many by theFederal government. The GSA has usedlow-energy approaches for some of itsbuildings. Several Federal facilities thatfeature low-energy design strategies arein the design phase, under construction,or recently completed, including anenvironmental learning center on theNational Mall in Washington, D.C., anda 570,000-square-foot Federal courthousein Phoenix, Arizona. The National ParkService (NPS) has integrated passive

36


solar strategies into new employee hous-ing units. NPS houses in Grand Canyonand Yosemite National Parks are includedin the DOE Exemplary Buildings pro-gram. Projects have been completed orare in progress at Grand Teton NationalPark, Hovenweep National Monument,and Capitol Reef National Park. TheDepartment of Defense is also usingthese low-energy strategies.

Federal Sites

Excellence in Facility Management, FiveFederal Case Studies (1998). National Institute of Building SciencesPhone: 202-289-7800E-mail: [email protected] site: http://www.nibs.org/fmochome.htm

The case studies included in this docu-ment are: (1) U.S. Department of Agri-culture Headquarters, (2) CarbondaleFederal Building, (3) Merritt IslandLaunch Annex, (4) Naval StationEverett, and (5) Defense LogisticsAgency.

National Park Service EmployeeHousing at Capitol Reef National Park

National Renewable Energy LaboratoryHigh-Performance Buildings ProgramGolden, ColoradoPhone: 303-275-3000Web site: http://www.nrel.gov/buildings/highperformanceDetailed case studies of state-of-the-art,low-energy buildings; pictures are avail-able for download.

The Naval Facilities Engineering Com-mand has completed several projectsthat demonstrate low-energy designprinciples. A physical fitness center atCamp Pendleton, California; a $7.8 mil-lion project in Sugar Grove, WestVirginia; and a restoration project at the Washington Navy Yard.

Brown, Linda R. “SERF: A Landmark inEnergy Efficiency.” (May/June 1994).Solar Today, American Solar EnergySociety.

U.S. Fish and Wildlife Service NationalEducation and Training Center, Shep-erdstown, West Virginia. A FEMP case

study will soon be available. Among ahost of energy-efficient features, the center incorporates passive solar designstrategies. In winter, large southern win-dows capture solar gain, and brick floorsbehind windows store heat. Windowsare made of high-performance glass. In summer, extended rooflines (over-hangs) and landscaping provide opti-mum shading. Some windows are fittedwith sunscreens, which also help reducesummer cooling loads.

Non-Federal Sites

Besser Company manufacturing facility,Alpena, Michigan. By Innovative Design.Energy conservation, daylighting.

Blue Cross/Blue Shield building in NewHaven, Connecticut. The 21,000-square-foot building has deep overhangs on the south façade to protect it from directsolar radiation in summer and to reducecooling loads. An atrium divides thebuilding into two sectors. Light shelveson façades and in the atrium project nat-ural light deep into the space. The proj-ect was completed in 1990; EllenzweigAssociates, Inc., were the architects.

Brown Summit Youth Dormitory cabins,North Carolina. By Cooper-LeckyCUH2A, LLP. Natural ventilation.

Buildings for a Sustainable America CaseStudies, American Solar Energy Society,303-443-3130, [email protected], http://www.ases.org/solar and Sustainable BuildingsIndustry Council (formerly PassiveSolar Industries Council), 202-628-7400,[email protected], http://www.sbicouncil.org, with funding from U.S.Department of Energy. A collection of 18 case studies, with easy-to-read sum-maries, thorough project details, andphotographs.

The Florida Solar Energy Center (FSEC)is building a state-of-the-art complex(office building, visitor’s center, and laboratories) for its new facility inCocoa, Florida. The objective is to design and construct the most energy-efficient facility possible within the limitsof Florida’s hot and humid climate. For a detailed analysis of the low-energydesign strategies used, check the FSEC

Web site: http://www.fsec.ucf.edu/About/TOUR/Tourhome.htm

Illinois Department of Energy andNatural ResourcesContact: R. Forrest LupoPhone: 217-785-3484

Massachusetts State TransportationBuilding, Boston, MassachusettsA solar water-heating system installed in1982 cost $250,000 but saves $26,280 peryear in avoided electricity costs. At thisrate, the system will pay for itself in 9.5years. Four thousand square feet ofclosed-loop propylene glycol solar col-lectors enable the solar water heaters to operate year-round, even though theoutside temperature is below freezingfor extended periods of time. The collec-tors supply 83% of the building’s annualdomestic hot water needs, offsettingroughly 5,800 gallons of oil annually.

Contact: Martha Goldsmith, Director,Office of LeasingCommonwealth of MassachusettsPhone: 617-727-8000

Sacramento Department of Transpor-tation BuildingUses nighttime flushing and passivesolar cooling with atrium. Contact: Craig HoellwarthPhone: 916-683-8378

Union of Concerned Scientists buildingCambridge, MassachusettsPhone: 617-547-5552E-mail: [email protected] site: http://www.ucsusa.org

Utah Department of Natural Resources(profiled in Solar Today, American SolarEnergy Society, July/August 1997)

For Further InformationTrade/Professional Organizations

American Council for an EnergyEfficiency Economy (ACEEE)

Alliance to Save Energy

American Institute of ArchitectsCommittee on the EnvironmentWashington, D.C.Phone: 202-626-7515Web site: http://www.e-architect.com

37


American Portland Cement AllianceWashington, D.C.Phone: 202-408-9494Web site: http://www.portcement.org

American Solar Energy SocietyPhone: 303-443-3130E-mail: [email protected] site: http://www.ases.org

American Society of Heating,Refrigeration, and Air-ConditioningEngineers (ASHRAE)Atlanta, GeorgiaPhone: 404-636-4800Web site: http://www.ashrae.org

American Society for Testing andMaterialsWest Conshocken, PennsylvaniaPhone: 610-832-9500Web site: http://www.astm.org

Association of Energy EngineersAtlanta, GeorgiaPhone: 770-447-5083Web site: http://www.aeecenter.org

Building Owners and Managers Association InternationalWashington, D.C.Web site: http://www.boma.org

Brick Institute of America, Mid East RegionNorth Canton, OhioPhone: 330-499-3001

Brick Industry AssociationReston, VirginiaPhone: 703-620-0010Web site: http://www.bia.org

Ceilings and Interior Systems Construc-tion AssociationSt. Charles, IllinoisPhone: 630-584-1919

Electricity Consumers Resource CouncilWashington, D.C.Phone: 202-682-1390

Energy Efficient Building Association(EEBA)Minneapolis, MinnesotaPhone: 612-851-9940E-mail: [email protected]

Illuminating Engineering Society ofNorth AmericaNew York, New YorkPhone: 212-248-5000

International Masonry InstituteAnn Arbor, MichiganPhone: 313-769-1654

National Association of Energy ServiceCompaniesWashington, D.C.Phone: 202-822-0952

National Association of Home BuildersWashington, D.C.Phone: 202-822-0200 (bookstore: exten-sion 463)Web site: http://www.nahb.com

National Concrete Masonry AssociationHerndon, VirginiaPhone: 703-713-1900Web site: http://www.ncma.org

National Electrical ManufacturersAssociationRosslyn, VirginiaPhone: 703-841-3200

National Fenestration Rating CouncilSilver Spring, MarylandPhone: (301) 588-0854Web site: http://www.nfrc.org

National Institute of Building SciencesPhone: 202-289-7800E-mail: [email protected] site: http://www.nibs.org/fmochome.htm

National Society of ProfessionalEngineersAlexandria, VirginiaPhone: 703-684-2800Web site: http://www.nspe.org

National Wood Window and DoorAssociationDes Plaines, IllinoisPhone: 847-299-5200Web site: http://www.nwwda.org

North American Insulation Manufac-turers AssociationAlexandria, VirginiaPhone: 703-684-0084Web site: http://www.naima.org

North Carolina Solar CenterPhone: (919) 515-3480

Northeast Sustainable EnergyAssociationPhone: 413-774-6051E-mail: [email protected] site: http://www.nesea.org

Solar Energy Industries AssociationWashington, D.C.Web site: http://www.seia.org

Southface Energy InstituteAtlanta, GeorgiaPhone: 404-872-3549E-mail: [email protected] site: http://www.southface.org

Sustainable Buildings Industry Council(SBIC) (formerly Passive SolarIndustries Council)Washington, D.C.Phone: 202-628-7400E-mail: [email protected] site: http://www.sbicouncil.org

U.S. Green Building Council (USGBC)San Francisco, CaliforniaPhone: 415-543-3001E-mail: [email protected] site: http://www.usgbc.org

Design Guides

Designing Low-Energy Buildings: PassiveSolar Strategies and ENERGY-10 Software;Passive Solar Design Strategies: Guidelinesfor Home Building; Low-Energy, SustainableBuilding Design for Federal Managers (Sus-tainable Buildings Industry Council [for-merly Passive Solar Industries Council])Phone: 202-628-7400E-mail: [email protected] site: http://www.sbicouncil.org

General Services Administration/PublicBuildings Service—Proposed Comprehen-sive Building Commissioning

LEED™ (Leadership in Energy and Envi-ronmental Design) Rating System,Version 2.0, available athttp://www.usgbc.org

Sustainable Building Technical Manual:Green Building Design, Construction andOperations, Public Technology, Inc.U.S. Green Building CouncilU.S. DOE, U.S. EPA, 1996.

Whole Buildings Design Guide, a federallysponsored, vertical portal to a widerange of building specific criteria, tech-nology, and product information.Web site: http://www.wbdg.org

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Utility, Information Service, or Govern-ment Agency Tech-Transfer Literature

Utility Sources

American Gas AssociationArlington, VirginiaWeb site:http://www.aga.com

Edison Electric InstituteWashington, D.C.Phone: 202-508-5557Web site: http://www.eei.org

The Electricity Consumers ResourceCouncilWashington, D.C.Phone: 202-682-1390E-mail: [email protected] site: http://www.elcon.org

Electric Power Research InstitutePalo Alto, CaliforniaPhone: 650-855-2000Web site: http://www.epri.com

National Association of RegulatoryUtility CommissionersWashington, D.C.Phone: 202-898-2200Web site: http://www.naruc.org

National Association of State UtilityConsumer AdvocatesWashington, D.C.Phone: 202-727-3908Web site: http://www.nasuca.org

Public Utilities ReportsVienna, VirginiaPhone: 703-847-7720, 800-368-5001 E-mail: [email protected] site: http://www.pur.com/

General Information Sources

Energy Design UpdateCutter Information Corp.37 Broadway, Suite 1Arlington, Massachusetts 02174-5552Phone: 800-964-5118Web site: http://www.cutter.com/energy/

Environmental Building NewsRR 1, Box 161Brattleboro, Vermont 05301 Phone: 802-257-7300;Web site: http://www.ebuild.com

E Source, Inc.Boulder, Colorado, Phone: 303-440-8500Web site: http://www.esource.com

Florida Solar Energy CenterPhone: 407-638-1015Web site: http://www.fsec.ucf.edu

International Energy AgencyWeb site: http://www.iea.org

Iris Catalog: Publications, Videos and Soft-ware for Green ConstructionIris Communications, Inc.P.O. Box 5920Eugene, Oregon 97405-9011Phone: 800-346-0104Web site: http://www.oikos.com

ReInState, a guide to state-by-state renew-able energy and sustainable develop-ment resources, including case studies,products and services, utility informa-tion, programs and policies, and energyusage and design data for each state.Web site: http://www.crest.org/gem.html

American National Standards Institute

Government Sources

Energy Efficiency and RenewableEnergy ClearinghouseMerrifield, Virginia, Phone: 800-363-3732E-mail: [email protected] site: http://www.eren.doe.gov

Energy Science and TechnologySoftware CenterWeb site: http://www.osti.gov/estc

Federal Laboratory Consortium1850 M Street, NW, Suite 800Washington, D.C. 20036FLC Locator: 609-667-7727Web site: http://www.Federallabs.org/

Guiding Principles of Sustainable DesignU.S. Department of the Interior National Park ServiceDenver, Colorado: GPO, 1993.

Lawrence Berkeley National LaboratoryBerkeley, CaliforniaPhone: 415-486-5771Web site: http://www.lbl.gov/

National Energy Information CenterWashington, D.C.Phone: 202-586-1181E-mail: infoctr @eia.doe.gov

National Institute of Standards andTechnologyWashington, D.C.Web site: http://www.nist.gov

National Oceanic and AtmosphericAdministration (NOAA)Phone: 704-271-4800E-mail: [email protected] site: http://www.ncdc.noaa.gov

National Renewable Energy LaboratoryWeb site: http://www.nrel.gov/buildings/highperformance

National Technical Information ServiceWashington, D.C.Phone: 800-553-6847Web site: http://www.fedworld.gov

Oak Ridge National LaboratoryBuilding Technology Center Web site: http://www.ornl.gov/ornl/btc

Office of Scientific and Technical InformationOak Ridge, TennesseePhone: 423-576-1188. Technical reports:423-576-8401

Partnership for Advancing Technologyin Housing (PATH)U.S. Department of Housing and UrbanDevelopment Phone: 202-708-1600Web site: http://www.pathnet.org

Procuring Low-Energy Design andConsulting Services: A Guide for FederalBuilding Managers, Architects, andEngineers, 1997Phone: 800-DOE-FEMPWeb site: http://www.eren.doe.gov/femp/

Sacramento Municipal Utility DistrictPhone: 916-732-6679

Sandia National LaboratoriesPhone: 505-844-3077 Web site: http://www.sandia.gov/EE.htm

U.S. Department of EnergyBuilding TechnologyState and Community ProgramsPhone: 202-586-2998

U.S. Environmental Protection AgencyEnergy Star ProgramWeb site: http://www.epa.gov

Codes and Standards

Executive Order 13123 mandatesimprovements in energy efficiency and water conservation in Federal buildings nationwide, including cost-effective investments (payback of less

39


than 10 years) in low-energy buildingdesign and active solar technologies.

10 CFR 435 establishes performance stan-dards to be used in designing newFederal commercial and multifamilyhigh-rise buildings. Some of the guide-lines are relevant to retrofits.

10 CFR 436 establishes procedures fordetermining the life-cycle cost effective-ness of energy conservation measuresand for prioritizing energy conservationmeasures in retrofits of existing Federalbuildings.

In general, building codes and standardsaddress specific technologies and mini-mum requirements for building energyefficiency. They do not address wholebuilding performance. A well-designed,low-energy building can exceed existingFederal codes, as well as commercialcode (ASHRAE 90.1—Energy EfficientDesign of New Buildings Except Low-Rise Residential Buildings), by as muchas 50%.

Documents and Other References

American Institute of Architects, Com -mittee on the Environment, Energy,Environment and Architecture, Washing-ton, D.C., 1991.

Ander, Gregg, Daylighting Performanceand Design, New York, New York, VanNostrand Reinhold, 1998.

Balcomb, J. Douglas, editor. Passive SolarBuildings. Cambridge, Massachusetts,MIT Press, 1992.

Bobenhausen, William, Simplified Designof HVAC Systems. New York, John Wileyand Sons, Inc., 1994.

Idea exchange among facility managersWeb site: www.fmdata.com

Interstate Renewable Energy Council15 Haydn StreetRoslindale P.O.Boston, Massachusetts 01131-4013 Phone: 617-323-7377

International Energy Agency SolarHeating and Cooling Programme.Passive Solar Commercial and InstitutionalBuildings: A Sourcebook of Examples andDesign Insights. West Sussex, UnitedKingdom, John Wiley and Sons, Ltd.,1994.

National Institute of Building Scienceswww.nibs.org

Productivity Studies

• www.workplaceforum.com

• Miller, Burke, Buildings for a Sustain-able America Case Studies; Daylighting and Productivity at Lockheed, Boulder,Colorado, American Solar EnergySociety.

• Joseph Romm and William Browning,Greening the Building and the Bottom Line:Increasing Productivity through Energy-Efficient Design, Snowmass, Colorado,Rocky Mountain Institute, 1994.

Steven Winter Associates, Inc., ThePassive Solar Design and ConstructionHandbook, New York, John Wiley andSons, Inc., 1998.

Tuluca, Adrian; Steven Winter Asso-ciates, Inc., Energy-Efficient Design andConstruction for Commercial Buildings.New York, McGraw-Hill, 1997.

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41

AppendixesAppendix A: Climate and Utility Data Sources

Appendix B: Federal Life-Cycle Costing Procedures and the Building Life Cycle Cost (BLCC) Software


42

Appendix A: Climate and Utility Data SourcesEnergy User News includes a ranking of electricity and gas utility prices by state in each of its monthly issues. Available athttp://www.energyusernews.com.

NOAA provides detailed available climate data and summaries for sites in or near a locality. Call 704-271-4800, e-mail requeststo [email protected], or available on the World Wide Web at http://www.ncdc.noaa.gov.

Opportunities for Renewable Energy Supply in New Buildings (Solar Potential Maps). A Buildings for a Sustainable America Educa-tion Campaign Resource from the Sustainable Buildings Industry Council, Washington, D.C. Funded by the U.S. DOE, researchedand produced by Mark Kelley and Henry Amistadi of Building Science Engineering in Harvard, Massachusetts. For more infor-mation, call 202-628-7400, send e-mail to [email protected], or access the SBIC Web site at http://www.sbicouncil.org.

Putting Energy into Profits. U.S. Environmental Protection Agency, #430-B-97-040, December 1997. Five U.S. climate zones aremapped, showing average annual energy use and average annual energy costs for specific building types. Available fromGovernment Printing Office, Superintendent of Documents, Washington, DC 20402, or call 202-512-1800.

Appendix B: Federal Life-Cycle Costing Procedures and the Building Life Cycle Cost (BLCC)SoftwareFederal agencies are required to evaluate energy-related investments on the basis of life-cycle costs (10 CFR 436). Life-cycle costanalysis (or life-cycle costing [LCC]) is a means of predicting the overall cost of building ownership, including initial costs, oper-ating costs for energy, water and other utilities; personnel costs; and maintenance, repair, and replacement costs. LCC analyzeschanges to the building, including all significant costs over the predicted life of the building. It can be used to refine the design to ensure the facility will provide the lowest overall cost of ownership consistent with its desired quality and function.

Analysis tools such as the National Institute of Standards and Technology’s (NIST) BLCC computer program performs calcula-tions to predict life-cycle costs, providing an economic analysis of proposed capital investments that are expected to reduce long-term operating costs of buildings. BLCC is designed to comply with 10 CFR 436. ERATES (electricity rates) is another computerprogram from NIST that calculates monthly and annual electricity costs for a facility under a variety of electric rate schedules.ERATES block-rate and demand-rate schedules can be imported by BLCC. BLCC is available from the FEMP Help Desk at 800-566-2877.


Federal Energy Management ProgramThe Federal Government is the largest energy consumer in the nation. Annually, in its 500,000 buildings and 8,000 locations worldwide, it uses nearly two quadrillion Btu (quads) of energy, costing over $8 billion. This represents 2.5% of all primary energy consumption in the United States. The Federal Energy Management Program was established in 1974 to provide direction, guidance, and assistance to Federal agencies in planning and implementing energy management programs that will improve the energy efficiency and fuel flexibility of the Federal infrastructure.

Over the years, several Federal laws and Executive Orders have shaped FEMP’s mission. These include the Energy Policy and Conservation Act of 1975; the National Energy Conservation and Policy Act of 1978; the Federal Energy Management Improvement Act of 1988; and, most recently, Executive Order 12759 in 1991, the National Energy Policy Act of 1992 (EPACT), Executive Order 12902 in 1994, and Executive Order 13123 in 1999.

FEMP is currently involved in a wide range of energy-assessment activities, including conducting New Technology Demonstrations, to hasten the penetration of energy-efficient technologies into the Federal marketplace.

The Energy Policy Act of 1992, and sub-sequent Executive Orders, mandate thatenergy consumption in Federal build-ings be reduced by 35% from 1985 levelsby the year 2010. To achieve this goal, theU.S. Department of Energy’s FederalEnergy Management Program (FEMP)is sponsoring a series of programs toreduce energy consumption at Federalinstallations nationwide. One of theseprograms, the New Technology Demon-stration Program (NTDP), is tasked toaccelerate the introduction of energy-efficient and renewable technologiesinto the Federal sector and to improvethe rate of technology transfer.

As part of this effort, FEMP is sponsoringa series of publications that are designedto disseminate information on new andemerging technologies. New TechnologyDemonstration Program publicationscomprise three separate series:

Federal Technology Alerts—longersummary reports that provide details on energy-efficient, water-conserving, and renewable-energy technologies that have been selected for further study for possible implementation inthe Federal sector.

Technology Installation Reviews—concise reports describing a new tech-nology and providing case study results,typically from another demonstrationprogram or pilot project.

Technology Focuses—brief informationon new, energy-efficient, environmen-tally friendly technologies of potentialinterest to the Federal sector.

About FEMP’s New Technology Demonstration Program

For More Information

FEMP Help Desk(800) 363-3732

International callers please use(703) 287-8391

Web site: www.eren.doe.gov/femp

General Contacts

Ted CollinsNew Technology Demonstration Program Manager

Federal Energy Management Program

U.S. Department of Energy1000 Independence Ave., SW, EE-92Washington, D.C. 20585Phone: (202) 586-8017Fax: (202) [email protected]

Steven A. ParkerPacific Northwest National Laboratory

P.O. Box 999, MSIN: K5-08Richland, WA 99352Phone: (509) 375-6366Fax: (509) [email protected]

Technical Contact

Nancy CarlisleNational Renewable Energy Laboratory

1617 Cole Boulevard, M.S. 2723Golden, CO 80401Phone: (303) 384-7509Fax: (303) [email protected]

Prepared for the U.S. Department ofEnergy by the National RenewableEnergy Laboratory, a DOE nationallaboratory

DOE/EE-0249

July 2001


Printed with a renewable-source ink on paper containing at least 50% wastepaper, including 20% post consumer waste

Log on to FEMP’s New Technology Demonstration ProgramWeb site

http://www.eren.doe.gov/femp/prodtech/newtechdemo.html

You will find links to:

• An overview of the New Technology Demonstration Program

• Information on the program’s technology demonstrations

• Downloadable versions of program publications in Adobe Portable Document Format (PDF)

• A list of new technology projects underway

• Electronic access to the program’s regular mailing list for new products when they become available

• How Federal agencies may submit requests for the program to assess new and emerging technologies.