Application of Pollution Prevention Tools in Energy Efficiency Assessments

S. Ghose, A. Kumar, and C. Varadarajan

Department of Civil EngineeringThe University of Toledo

Toledo, Ohio 43606

ABSTRACT

This study presents the use of four Pollution Prevention (P2) tools in performing energy

assessments in Ohio with the help of local NIST Centers. The assessments covered the

various uses of energy within the plants, which included lighting, motors, HVAC systems

and water heaters. A careful study of the lighting plan and an onsite assessment of the

lighting distribution in the facilities were carried out. Details of motors, HVAC systems

and water heaters were obtained. The Energy Assessment Spreadsheet was used to

organize the input data and calculate a detailed break-up of the total annual energy

consumption and cost. The U.S DOE MotorMaster software program that analyses

motors and motor system efficiencies was run on all the motors to generate payback

amounts and periods for the replacement motors. The motors were also ranked based on

the payback amounts and periods to plan their replacement with energy efficient models.

The HVAC Checklist was used to determine the required capacities of chillers and

boilers, and compare that with the installed capacities to identify the inefficient ones.

Based on the results from the above three programs various measures were suggested for

reducing the energy consumption. The last program was the Emission Reduction

Calculator that was used to estimate the reduction in emissions as a result of reduced

energy consumption. The paper discusses the usefulness of these tools in any energy

efficiency assessment that, in turn, can facilitate pollution prevention.

INTRODUCTION

Growing awareness to the problem of pollution and associated regulatory policies by

governmental environmental agencies has created a lot of interest in the area of ‘Pollution

Prevention’ (P2). Businesses, environmental groups and citizens are getting involved on

activities related to Pollution Prevention. The U.S. Pollution Prevention Act of 1990

states that pollution should be prevented or reduced at the source whenever feasible. The

U.S. Environmental Protection Agency further defines pollution prevention as the

exercise of practices that reduce or eliminate the creation of pollutants through increased

efficiency in the use of raw materials, energy, water, and other resources, and through

protection of natural resources by conservation. The need for the pollution prevention has

become stronger than ever because of environmental challenges, cost competitions, and

consumer demands. More specifically, pollution prevention in an industrial environment

necessitates in-plant practices that include process modifications, feedstock substitutions,

product reformulations, management practices or housekeeping alterations, recycling

within industrial processes, and equipment replacements or modifications.

The changes in management practices or housekeeping alterations would include regular

and preventive maintenance, training, inventory control, and improvements in

housekeeping. Pollution prevention and source reduction are used interchangeably

throughout the U.S. and mean the same thing. Methods for achieving waste reduction

divide conveniently into two basic types: pollution prevention or source reduction, and

recycling.

This paper discusses the use of four P2 tools that can be used in energy efficiency

assessments. Three of these tools, namely the Energy Assessment Spreadsheet, the

HVAC Checklist, and the Emission Reduction Calculator, were developed at the Civil

Engineering Department, The University of Toledo, in the course of real-life energy

assessment projects, the most important of which was the one for a big auto-parts

manufacturer in Ohio. All these three tools, in a more generic and easy-to-use format,

have been made available at the University’s Pollution Prevention Tools Web site

(http://p2tools.utoledo.edu/). Small to medium sized businesses can download and use

these tools for their own pollution prevention work to achieve enhanced environmental

quality and savings in cost. The fourth tool used was the software program called

MotorMaster that was developed by the Washington State University Cooperative

Extension Energy Program (the Energy Program) with funding from the U.S. Department

of Energy (USDOE) via the Office of Industrial Technologies' Best Practices Program

(formerly the Motor Challenge Program). It is available for download from the Office of

Industrial Technologies’ software tools Web site

(http://mm3.energy.wsu.edu/mmplus/default.stm).

In addition, a host of other P2 tools are available from various Web sites. A

comprehensive list of such sites can be found at http://p2tools.utoledo.edu/alltools.htm.

Further, a list of energy related sites is available at

http://p2tools.utoledo.edu/websites.htm.

ENERGY ASSESSMENT SPREADSHEET

Spreadsheets provide a simple yet excellent tool for organizing input data and performing

calculations with them, and hence form an inevitable part of any energy assessment

project. Spreadsheets can be effectively coded to auto-generate desired results with input

data.

The Energy Assessment Spreadsheet developed has separate sections for the different

areas of energy consumption generally found in the industry, viz. lighting, motors, and

HVAC systems. The lighting section is further divided into three sub-sections: Input

Data, Lighting Cost, and Lighting Cost Reductions. Inputting the wattage, quantity,

annual operating hours for each category of fixtures, and the unit cost of energy

automatically generates the annual energy consumption as well as the operational cost for

each individual fixture types and also the totals. With the details of specific savings

opportunities and corresponding percent reductions in cost, the annual savings in cost are

estimated. Similarly, in the motor section, entering the details for each type of motors

(wattage, quantity, and annual operating hours) and the unit energy cost generates the

energy consumption and operating cost for each motor type and also the totals. HVAC

systems are generally multi-component systems, and so the HVAC section requires the

input details for various constituent components of each system, and calculates the

energy consumption and operating cost of each component individually, each composite

system as well as the totals.

With the given instructions, the Energy Assessment Spreadsheet is easy to use. It

provides a complete break-up of the total energy consumption and cost, which can help in

identifying avenues for savings and improvement.

HVAC CHECKLIST

The HVAC Checklist, also developed using a spreadsheet, provides a list of measures to

improve an existing HVAC system and make it more energy efficient. It has separate

checklists for general HVAC Strategy, Chiller Retrofit, Boiler Retrofit, Pumping System

Upgrades, Fan System Upgrades, and Low-Cost Improvements. All these checklists help

in forming an effective action-plan for overall improvements. It also has two separate

sections on Chiller System Rightsizing and Boiler System Rightsizing. With a few input

parameters of an existing chiller or boiler, these sections calculate the corresponding

required loads and capacities and compare them with the existing ones. This comparison

helps in deciding whether rightsizing of the existing systems is necessary as both

oversized and undersized systems can prove to be extremely inefficient. With the given

set of instructions that include how to gather the required input data physically from the

system, it is an easy to use tool that can be handy in an energy assessment.

EMISSION REDUCTION CALCULATOR

The Emission Reduction Calculator is a software tool that enables the user to have an

estimate of the pollution prevention aspect of an energy conservation project. It has been

designed to calculate the reduction in emissions of three criteria pollutants (SO2, NOx and

CO2) in terms of saved energy consumption. The theoretical basis of the ERC tool stems

from the fact that for every ton of solid, liquid or gaseous fuel saved there is a reduction

in emission of the criteria pollutants mentioned. With the analogy that for saving every

kWh of electricity there is a corresponding reduction in consumption of fuel used, the

tool calculates the reduction in emission of the pollutants in terms of saved kilowatt-

hours. The U.S. Environmental Protection Agency (EPA) has developed emission factors

for different states. These emission factors form the basis of calculations performed by

the ERC tool. The tool multiplies the emission factor for each of the three pollutants with

the reduction in the amount of kilowatt-hours saved to get the emission reduction.

Developed in Visual Basic, the tool has a very user-friendly interface and guides the user

through onscreen instructions. It can generate a summary of results both in a text file

format and a spreadsheet format.

MotorMaster

MotorMaster is a software program that analyzes motors and motor system efficiencies.

It can identify inefficient or oversized facility motors and compute the energy and

demand savings associated with selection of a replacement energy-efficient model. It is a

powerful motor and motor-driven equipment energy management tool that has expanded

Inventory Management, Maintenance Logging, Lifecycle Costing, Savings Tracking and

Trending functions, Conservation Analysis, Savings Evaluation, Energy Accounting, and

Environmental Reporting Capabilities. It has a huge in-built database of motors with

various specifications from major manufacturers.

As part of the energy assessment in any plant, MotorMaster can be run on all the motors

to generate payback periods and amounts for the replacement motors and plan the

replacement strategy. More details of the software are available at the Website mentioned

in the introduction.

A CASE STUDY

THE ASSESSMENT

Energy assessment was performed for an automobile parts manufacturing facility in

Ohio. The assessment was intended to cover the various uses of energy within the plant

and the areas covered were lighting, motors, HVAC systems and water heaters used in

the plant. All the four tools mentioned were used in the assessment, and avenues to effect

more energy efficient consumption of power were explored.

A. LIGHTING

Need for Lighting Retrofit

Lighting consumes 25 – 30% of energy in commercial buildings, and is a primary source

of heat wastage. Upgraded lighting systems improve lighting quality to increase occupant

comfort and productivity. A lighting upgrade is an investment not only in reducing power

consumption but also in improving the performance of the building in supporting its

occupants. There are several clear-cut measures that can be taken to improve energy

savings. New, much improved light sources are now available that provide considerable

more light per unit of energy. Most newer fixtures offer better light control, putting light

where it is needed rather than wasting a great deal of the light produced by the lamp

(Task Lighting). The position of the light source in relation to both the viewed surface

and the eye is critical. Replacement of older fixtures and lamps with the newer, improved

ones can greatly improve efficiency. Employing lighting controls is a good way to

conserve energy. Controlling when and where the lights are used, how long they are on,

and how bright they are, all can be a major factor in conserving energy. Devices range

from a simple on/off switch to computers programmed to activate light automatically.

Turning lights off when not needed, using individual controls rather than lighting large

areas with a single switch and using timers help in energy savings. Some of the newer

applications use motion sensors and photo-sensors for room light control, and such

systems are also effective for outdoor applications. Finally, lamp and fixture maintenance

can also be an important factor. Unclean fixtures covered with dust and dirt can reduce

light output in some cases up to 50 percent.

Methodology

The lighting survey involved a careful study of the lighting plan made available by the

company. Certain missing portions of the lighting plan necessitated an onsite assessment

of the lighting distribution in the facility. A lighting level survey of the facility (factory

area) was also carried out to measure the effectiveness of the lighting measures.

Details of the various types of lighting fixtures (wattage, usage hour, and quantity) were

entered into the spreadsheet to calculate the annual power consumption and cost for each

type and also the totals. The following are screenshots of the spreadsheet.

Figure 1: Lighting Fixture Details

Figure 2: Lighting Cost (Assuming Energy Cost = $0.05/kWh)

Findings

1. Levels of lighting varied from 13 foot-candles (fc) at the boundary walls to about

64 fc at the central walkway.

2. Certain storage areas were dimly lit with the level as low as 4 fc.

3. At certain workstations provided with individual lighting, levels were as high as

127 fc.

4. The levels at a bay were measured. The level outside on a cloudy day was 144 fc

whereas the lighting intensity just inside the bay door was only 17 fc.

5. Storage areas on the west wing had a lot of discrepancies in lighting level. Some

aisles showed levels as low as 15 fc while others showed 45 fc.

Recommendations

1. Use of electronic diffusers and specular reflectors while retrofitting all fixtures.

2. Replacement of magnetic ballasts with more efficient electronic ballasts.

3. Lowering of type F lights to increase lighting levels in the plant.

4. Change in the arrangement of lamps thus reducing the number of fixtures while

retrofitting.

5. Replacement of the existing high wattage metal halides with either improved

metal halides or fluorescent lamps.

Savings Estimate

Converting the existing type F fixtures to a 320-watt lamp would decrease energy usage

from about 770,000 kWh to 616,000 kWh at a rate of$ 0.05/kWh; this would save $7,700

per year. Decreasing the total number of the 320-watt fixtures and careful rearrangement

could further reduce the energy used for lighting. A 5% decrease would reduce cost by

$1600.

The screen shot of the spreadsheet below shows the estimated reduction in energy if the

recommendations were implemented.

Figure 3: Energy Reduction Estimates

B. MOTORS

Motor driven equipment accounts for about 60% of the electricity consumed in the U.S.

industrial sector. Motor systems consume approximately 290 billion kWh per year

nationwide. Improvements to motor systems in the industries could yield enormous

energy and cost savings. It is estimated that energy used by motors can be reduced by

18% through the application of proven efficiency technologies and sound energy

management practices.

Methodology

Data on various motors (wattage, usage hour, and quantity) made available from the plant

was entered into the assessment spreadsheet to calculate the power consumption and cost

of each type. The U.S DOE MotorMaster software program was then run on all the

motors in the plant to generate payback periods and amounts for the replacement motors

and develop a working plan to replace existing motors with more efficient ones. The

motors were ranked based on the payback periods, payback amounts and the energy and

cost savings.

The following screenshots of the spreadsheet show the energy consumption, cost, and the

ranking of some of the motors.

Figure 4: Payback for Motors based on Existing and Replacement Efficiencies

Figure 5: Ranking of Motors for Replacement

Findings and Recommendations

During the assessment some of the motors in the plant were found to be not highly

efficient and could be replaced with more efficient ones. Estimated payback amounts and

periods for these motors favored the replacements. Recommendations were made to

replace the inefficient motors with efficient ones according to the ranking developed on

the basis of payback amounts and periods.

C. HVAC SYSTEMS

HVAC systems are the largest single consumers of energy in buildings. Existing

capacities of these multi-component systems often do not match the actual required

capacities. Oversized systems cycle more often, leaving occupants uncomfortable with

broader temperature swings. Rightsizing the systems to maximize the benefits of cooling

and heating load reductions can result in significant energy savings. Knowing the

optimized cooling and heating loads can help to accurately rightsize the system to meet

the maximum loads. Separate strategies can be developed for improving each individual

component of an HVAC system.

An integrated system approach for pumps transporting chilled water or condensed water

can reduce pumping system energy by 50 percent or more. Pumping systems can be made

more energy-efficient by replacing oversized impellers, pumps, and motors with

rightsized pumps and smaller, energy-efficient motors. Installing variable speed drives

(VSDs) on pump motors can result in a load reduction and a corresponding reduction in

motor speed, thereby reducing energy consumption. Fan systems can be upgraded and

made more efficient through rightsizing and the use of VSDs, improved controls and

efficient motors and belts. Other possible areas of improvement include proper

maintenance, controlled temperature settings, and installation of programmable

thermostats.

Methodology

The details of the systems were entered in the spreadsheet to calculate their energy

consumption and operational cost. The following is a screenshot of the spreadsheet.

Figure 6: HVAC Systems

Possible areas of improvement for efficient operation of the systems were identified and

strategies developed to reduce the energy consumption. The HVAC Checklist was used

to compare the capacities of the existing chillers and boilers with their required capacities

and identify the oversized ones for replacement.

Findings and Recommendations

1. Nearly 90% of the energy used by the air compressors showed up as waste heat.

Waste heat is a potential source for low temperature heating and could be used to

evaporate the water for mixed waste streams in order to reduce the quantity of

liquid wastes for disposal.

2. Installation of an economizer in the HVAC systems would reduce the need for the

refrigerant compressors for 2/3 of the year which could lead to energy savings of

about 67%.

3. Venting the waste heat away from the air compressors and air dryer inlets would

improve the overall efficiency of the unit. Venting the heat outside in the summer

and into the building interior as needed in the winter would also improve comfort.

4. Efficiencies of the air compressors are improved when intake air is cool.

Constructing ducting to allow outside air to be the source for the compressor inlet

air would improve efficiency.

5. Eliminating air leaks in the system is potentially the highest value improvement.

Significant air leaks in the system could cost thousands of dollars per year. Air

leaks could be difficult to detect and quantify due to noise in the plant. Ultrasonic

leak detection equipment could help locate and estimate the size of a compressed

air leak even during normal plant noise operations.

D. WATER HEATERS

Details of the water heaters in the plant were also entered in the assessment spreadsheet

to calculate the energy consumption and cost. The following is a screenshot of the

spreadsheet.

Figure 12: Water Heaters

SUMMARY OF ASSESSMENT

The following figure summarizes the energy consumption and the operational cost of the

different areas covered in the assessment. The areas have been ranked on their percentage

usage of the total consumption.

Figure 13: Percentage Usage of KW & KWH

EMISSION REDUCTION ESTIMATES

Assuming the total reduction in energy usage as a result of implementation of the various

recommendations in the range of 10% of the total Kilowatt-Hours consumed in a year,

the reduction amounted to about 816510 Kilowatt-Hours.

Using the Energy Reduction Calculator, the amount of reduction in CO2, SO2 and NOx

emissions were obtained. The results are shown below:

CO2 reduction (lbs/year)

SO2 reduction (lbs/year)

NOx reduction (lbs/year)

1469718 18721 6300 Figure 14: Emission Reductions

CONCLUSION

These four simple easy to use pollution prevention tools have been successfully used in

many energy efficiency assessments. Their application has resulted in considerable

savings in both time and effort. Many other types of P2 tools are also available that can

be used in such assessments. With the growing concern for energy efficiency and

pollution prevention, these tools can prove to be invaluable in these areas.

DISCLAIMER

The assessments were part of the Pollution Prevention Incentives for States (PPIS) Grant

Program funded by the U.S. Environmental Protection Agency (EPA). The opinions

expressed in the paper are those of the authors. References in the papers to any specific

commercial service or process, by trade name, trademark, manufacturer, or otherwise, do

not necessarily imply their endorsement or recommendation by the U.S. EPA.

WEB SITES AND REFERENCES

1. Energy Star Building Manuals, Heating and Cooling System Upgrades.

http://yosemite1.epa.gov/ESTAR/business.nsf/content/business_resources_upgr

adebuilding.htm (accessed March 2002).

2. Pollution Prevention Programs, U.S. Environmental Protection Agency,

http://www.epa.gov/ebtpages/pollpollutionpreventionprograms.html

3. Software Tools, Office of Industrial Technologies,

http://mm3.energy.wsu.edu/mmplus/default.stm

4. Pollution Prevention Tools, Air Pollution Research Group, The University of

Toledo,

http://p2tools.utoledo.edu/

5. A Manual of Recommended Practices, American Conference of Governmental

Industrial Hygienists, 24th Edition.

6. HVAC Systems and Equipments, American Society of Heating, Refrigerating

and Air-Conditioning Engineers, Inc., 2000.

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