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Energy Conservation ofCommercial Facilities

(Department Stores, General Merchandise Stores, and Shopping Centers)

Major points, measures, and successful cases of energyconservation of commercial facilities

The Energy Conservation Center, Japan

1

The first commitment period of Kyoto Protocol started in FY2008,

which requires us to achieve a target of reducing greenhouse gas

emissions to 6% below the base year (FY1990) levels by FY2012.

Approximately 87% of the greenhouse gas is comprised of carbon

dioxide (CO2) from energy consumption. The CO2 emissions have

been significantly growing especially in civilian business sectors and

enhancement of drastic measures has become an urgent need.

This brochure is intended for owners of commercial facilities and

persons in charge of energy conservation promotion or energy facility

management, explaining the points, measures and the case

examples of energy conservation based on our investigation data. We

hope that you wi l l f ind the in format ion tak ing account o f

characteristics in energy consumption particularly seen in operations

of commercial facilities helpful for your activities toward better energy

conservation practices.

Introduction

C O N T E N T S

1 Characteristics of Energy Consumption at Commercial Facilities……… 2

2 Energy Consumption Structure of Commercial Facilities ……………… 3

3 Energy Conservation Measures at Commercial Facilities……………… 5

4 Energy Conservation Measures for Different Departmentsof Commercial Facilities …………… 7

5 Energy Conservation Measures for Different Installations andEquipment at Commercial Facilities ………… 9

6 Successful Cases of Energy Conservation Measures ofCommercial Facilities ………………11

7 Effective Tools and Techniques for Promoting EnergyConservation by Improved Operation …………………14

The distribution of total floor space ofsurveyed buildings

Energy consumption trend oftypical facilities from each category

Energy consumption by target facilitiespercategory of business

The proportion of heat (fuel)and electricity consumption

Energy intensity of different categories of business

2

Major points, measures, and successful cases of energy conservation of commercial facilities

The following graphs show the characteristics of energy consumption at large commercial buildings in the size of designated energy management factories located in the middle part of the county (between Tokyo metropolitan area and Kansai metropolitan area), including 39 department stores, 12 general merchandise stores, and 15 shopping centers.

1 Characteristics of EnergyConsumption at Commercial Facilities

TJ/year

Total floor area (unit: ten thousand m2)

0 5 10 15 20

Department store General merchandise store Shopping center

1000

900

800

700

600

500

400

300

200

100

Department storey=4107.9x+1E+07（MJ）R2=0.8707

General merchandise storey=1960.9x+2E+07（MJ）R2=0.8194

Shopping centery=2360.7x+8E+06（MJ）R2=0.8134

0 4 5 6 7 8 9 10 11 12 1 2 3

MJ/m2/month

Department store

Shopping center

General merchandise store

Month of the year

500

400

300

200

100

0 1000 2000 3000 4000MJ/m2/year

Offices

Hotels

Hospitals

Department storesDepartment stores excluding

car parking space

General merchandise storesexcluding car parking space

Shopping centers excludingcar parking space

General merchandisestores

Shopping centers

0 20 40 60 80 100％

Electricity Heat (fuel)

Offices

Hotels

Hospitals

Department stores


Shopping centers

20

15

10

5

02 4 6 8 10 12 14 16 18 20

No of buildings

Total floor area (unit: ten thousand m2)

3

Energy intensity of commercial facilities vary depending on their types of business and/or operation styles. The following graphs illustrate the differences.In order to promote energy conservation initiative, it is necessary to know energy intensity of each department (such as food sales, commodity sales, and the sections behind the shop front). As a way of obtaining such information, ECCJ provides a tool for energy specific unit management (computer software to estimate energy intensity and their breakdowns) for free.

2

Average (MJ/m2/year)

Maximum (MJ/m2/year)

Median (MJ/m2/year)

Minimum (MJ/m2/year)

Number of facilities

Departmentstore

Generalmerchandise store

Shoppingcenter

Average of allcategories

394,1236,1493,8422,624 2,668 2,821 2,704

3,017 3,428 3,4293,760 4,273 4,7283,140 3,452 3,57212 15 （66）

Energy intensity of commercial facilities (Type 1 and Type 2 designated energy management factories) (excluding car parking space)

7000

6000

5000

4000

3000

2000

1000

0

<66 stores, arranged in order of energy consumption>

Department store

MJ/m2/year

General merchandise store Shopping center

50

40

30

20

10

0

％ Average 7% Average 29% Average 38%

12 general merchandisestores

15 shopping centers39 department stores

Energy Consumption Structure ofCommercial Facilities

Energy Conservation of Commercial Facilities(Department Stores, General Merchandise Stores, and Shopping Centers)

Proportion of car parking space to total floor space of commercial facilities

4

Energy consumption structures of general merchandise stores and department stores are shown below. The largest share of the general merchandise stores is represented by energy for air-conditioning, which accounts for approximately 40%, followed by lighting and electrical outlets, and chillers and refrigerators. The department stores have almost the same shares in lighting and electric outlets and air-conditioning, accounting together for almost 80% of total energy consumption.

Energy structure of commercial facilities

Sh

ares

of e

ner

gy

con

sum

ptio

nfo

r d

iffer

ent u

ses

Number of monthly customers of commercial facilities(proportion to 100% representing monthly average)

Average business hours ofcommercial facilities

70%

80%

90%

100%

110%

120%

130%

140%

150%

Jan. Feb. Mar. Apr. May. Jun. Jul. Aug. Sep.Oct. Nov. Dec.

Department store B

General merchandise stores AGeneral merchandise stores BDepartment store A

Category of business Average annualbusiness hours

Department stores3,633

（362 days）

4,030（364 days）


4,320（363 days）Shopping centers

Sh

ares

of e

ner

gy

con

sum

ptio

nby

diff

eren

t dep

artm

ents

Sh

ares

of f

loo

r ar

ea fo

rd

iffer

ent d

epar

tmen

ts

Sections behindthe shop front15.2％

Car parkingspace43.1％

Commoditysales31.0％ Food sales

5.1％

Food anddrink services2.4％

Cultural andleisure services3.2％

ELV･ESC 4.3%Ventilation, water supply/drainage, and other

6.6%

Others 5.4%

Auxiliarymachine

units1.9％Water0.5％

Hot water supplyand cooking6.7％

Hot water supply and cooking6.7％

Heatdistribution7.4％

Heat source31.4％

Electricaloutlets5.8％

Chillers and refrigerators10.4％

Mainmachine

units29.5％

Air6.9％Lighting

22.0％

Generalmerchandise

stores58,000㎡

Others5.4％Chillers and refrigerators10.4％

Motive power10.9％

Lighting andelectrical outlets

27.8％

Sections behindthe shop front21.2％

Car parkingspace2.1％

Food sales7.3％

Commodity sales64.1％



ELV･ESC6.9%

Ventilation,water supply/

drainage,and other2.9%

Others2.2%

Others2.2%

Auxiliarymachine units7.8％

Water2.9％

Heat distribution 9.2％

Heat source30.6％

Hot water supplyand cooking3.2％

Hot water supply and cooking3.2％

Electricaloutlets11.0％

Lighting28.9％

Chillers and refrigerators5.1％

Chillers and refrigerators 5.1％

Main machineunits22.8％

Air 6.3％

Departmentstores

82,000㎡

Motive power9.8％

Lighting andelectrical outlets

39.9％

Sections behind the shop front5.9％ Car parking space 0.2％

Food sales14.8％





frontSections behind the shop front8.8％

Car parking space 6.2％


Food sales34.3％



5

The following are energy conservation measures which are often implemented in commercial facilities. Their adoption rates vary depending on type of business.

3 Energy Conservation Measures atCommercial Facilities


WC

WC

WC

WC

WC

WC

Chiller

Space for handling/disposal of goods

Excess exhaust air

Total heatexchanger

Air-conditioningunits

Lifting pump

Electric roomAir-conditioning

pump

Central monitorand disaster

control center

Central monitorand disaster

control center

●Chang of vent i la t ion fan contro l method from a schedule-based to CO-concentration level-based method

●Dividing controllable lighting area into smaller partitions

Indoor car parking space

Carbon monoxide (CO) meter for controllingventilation based on CO concentration levelat car parking space

●On/off control of cooling tower fans

●Cleaning and replacement of fillers

●Control of cooling water concentration level

●Considerat ion of f ree cooling system

●Reduction of the number of units in service by implementing more optimized layout

●Enhance Inverter control (estimated energy conservation ratio: 30%)●Recycling of energy consumption using regenerative control device

for electric power (estimated energy conservation ratio: 15%)●Control (turning on and off) ventilation fans in elevator motor room

using a thermostatic system

Reduction of thermal load fromwindows, sashes, and glasses ●Reduc t ion o f w indow

space Enhance insulation and airtight sashes

●Use of heat reflecting or double-glazed glasses

Chiller●Energy conservation and reduction of

env i r onmen ta l bu rden t h rough modifying centrifugal (turbo) chillers using specified chlorofluorocarbon (CFCs) to chil ler units using CFC alternatives

●Divide required equipment capacity into appropriate units

●Change chilled-water temperature setting at summer and at intermediate seasons

Boiler●Optimization of air ratio●Dividing required equipment capacity

into several unitsEHP/GHP●Taking preventive measures against

short circuit of outdoor condensing units

●Reduce the length of coolant pipes

●Solar power generation●Solar heat water heater

Utilization of natural energy

●Stop outside air intake during warm-up operation●Control outside air intake by CO2 concentration level

(800 to 990 ppm)●Outside air cooling●Heat recovery using total heat exchanger●Intermittent operation of

air-conditioning units●Turning off air-conditioning units

before closing time

Air conditioning

Heat source

Cooling tower

●Adoption of high-efficiency fans●VAV (variable air volume) control●Control of revolution speed through installation of

inverter device to light duty fans●Replacement motors with higher efficiency ones

(estimated energy conservation ratio: 5%)●Installation of energy-saving belts (estimated energy

conservation ratio; 3 to 4%)

Reduction of power required to operate fans

Well water treatment system to produce drinking water

●Calculation and summarization of energy consumption data

●Scheduled operations●Monitoring of operations conditions●Management of indoor air quality

●Control of consumed energy●Measurements of electricity for

each feeder or transformer● I n s t a l l a t i o n o f f l ow m e t e r s ,

calorimeters, and thermometers

Control outside air intakeby CO2 concentration level

Improvement of various functions of building energy management system (BEMS)

Reduction of water consumption

Elevators

●Automatic water faucet●Installation of water-saving flush valves (estimated water

saving ratio: 20%)●Installation of motion sensor to urinals●Installation of imitation sound generating device in ladies toilet ●Use of treated wastewater as flush water●Installation of well water treatment system to produce

drinking water

ELVRestaurants

Shops

M

Shops

Shops

Shops

Shops

Shops

Shops

Car parkingspace

Entrance

6

Adoption rate of equipment and facilities designed forenvironmental improvement at commercial facilities

Adoption rate of energy conservationtechniques at commercial facilities

0 10 20 30 40 50 60 70 80％

Automatic water faucetAutomatic power factor

regulatorControl on the number of heat source

equipment units in serviceInverter-controlled lighting

Outdoor air cooling

Demand control systemControl on the number of

pumps in serviceInverter-control of pumps

Internal air isolationcontrol at starting

Device to drown outtoilet noises

High-efficient transformer

Variable air volume (VAV)control

Outdoor-air intake regulation

Ventilated air regulation

Energy-saving belt

Total heat exchanger

Daylight sensor

High-efficiency motor

System for reducingfoamed polystyrene

volumeWell water treatment system

to produce drinking waterand/or general service water

Pollution abatementsystem for

discharged water

Aeration andagitation pump

Compostingsystem

Improvement ordevelopment of recycled

wastewater facility

0 10 20 30 40 50％

●Use of energy-conserving food showcases●Installation of night covers (insulation covers)●Eliminat ing use of showcases which

discharge heat indoors

Food Showcases

●Improvement transformer to the high-efficiency one (total loss is reduced to one third of old type transformer)

●Review the balance of transformers load and re-configurate of them.●Separating feeders for daytime and nighttime systems so that the

transformer in the latter system can be turned off.●Turning on and off exhaust fans using a thermostat system●Reduction of peak demand (maximum power under electric

power-supply contract) through implementation of a heat storage system

●Demand control

●Improvement of efficiency in heat and electricity consumptions according to load levels

●Reduction of peak demand (maximum power under electric power-supply contract)

●Installation of absorption chillers with waste heat recovery system●Implementation of hot-water supply with waste heat recovery system

●Modification of the system to shorter distribution route●Use of wires with thicker size

●Prevention of outdoor air entry at entrances and exits●Checking that a damper is closed when air-conditioning is

turned off●Installation of airbrake room at door way ●Maintaining room air pressure positive

●Utilizing service space as a buffer area to insulate heat from exterior walls

●Place the openings in the lee of the building●Phased arrangement of air-conditioning space

●Use of less indirect lighting fixtures●Dividing lighting area controlled by switch circuit into smaller partitions●Changing room color to lighter tone●Use of less incandescent lamps●Scheduled lights on and off system●Use of high-frequency (Hf) lighting fixtures●Control of lighting system taking advantage of daylight●Maintenance of proper illuminance


Department store


Shopping center

Department store


Shopping center

Composting system

Night cover

Prevention of unnecessary outdoor airfrom entering into building

Reduction of electric distribution loss and power loss

Electric power receiving and transforming

Installation of cogeneration system

Floor planning

Indoor lighting

7

The following are energy conservation measures for different departments, which are helpful for you to promote your energy conservation initiative.

4 Energy Conservation Measuresfor Different Departments ofCommercial Facilities

Commodity Sales department

A majority of energy consumption in office is air-conditioning, lighting, and outlets. Unlike sales floor, where entirely turning lights on and off as scheduled is an effective measure, lighting equipments in administrative department are usually controlled separately using a switch on the wall. A company cafeteria has an energy consumption structure similar to food and drink service department.

Administrative department

Since offices and the back yards have different operating hours for different purposes, an individual air-conditioning should be adopted.Lighting area should be divided into smaller partitions to turn off lights wherever unnecessary.Temperature setting for air-conditioning should be at 20℃ during winter and 28℃ during summer.Lighting equipments should be replaced to inverter type.Daylight should be utilized for lighting in the office. A motion sensor device should be installed to turn on/off lights for such as locker rooms, etc.

❶

❷

❸

❹❺

Department stores often have a basement parking area, a mechanical parking lot and a three-dimensional parking lot, and a majority of large shopping centers has outdoor parking lot or outdoor parking with semi-open walls. A shopping centers with station buildings typically do not have their own car parking space and often share a public parking space with other facilities.The major energy consumption of car parking space is for ventilation and lighting, and it has fairly smaller energy density than other departments.

Car parking space

In addition to securing minimum necessary lighting level, the lighting area should be divided into smaller partitions to allow strict control based the number of cars parked in the area.A CO sensor device should be installed to control ventilation system based on the standard CO level.Alert drivers to encourage to stop idling practice.Some improvements which could make driving speed slower should be added in the drive ways in order to reduce exhaust gas emissions.

❶

❷

❸❹

This department has the largest share of floor area in a facility. In a department store, the commodity sales section on the first floor has particularly high lighting illuminance and a wide use of incandescent lamps, leading to significantly large electric power consumption for lighting. Another issue is that outdoor-air blowing into the building form entrances on the first floor puts a significant burden of its air-conditioning load.

Adopt air-break room at door way.Improved arrangement of lighting equipments with effective impact should be made so that the number of incandescent lamps can be reduced. Utilization of daylight for lighting purpose around entrances and near windows should also be considered.Energy-saving lighting equipments with inverter device should be installed.Excess air cooling or heating should be avoided.Outside air cooling should be implemented during winter and intermediate seasons.Proper amount of outside air intake should be taken in to the building in proportion to the number of occupant, with CO2 concentration level control during air-conditioning.

❶❷

❸❹❺❻

Importantpoints for

the measures

Importantpoints for

the measures

Importantpoints for

the measures


8

Importantpoints for

the measures

Importantpoints for

the measures

Food sales department is characterized by its high energy consumptions density, especially freezing / refrigeration for food, in contrast with its small area ratio in the facility. The customer density per certain area is larger than others, especially in the evening. In recent years, more cooking in sales area is needed due to increased demands for cooked foods, catering service, etc., resulting in upward trend of energy consumption for cooking.

Food sales department

Indoor temperature of supermarket is tends to be too lowered influenced by the chill of the freezing / refrigeration cases for foods. Such excess cooling should be avoidedFoods should be kept at proper temperature, avoiding excess cooling of open-type showcases.L-leakage of the chill after closing the store should be prevented using night covers or other measures. Glass doors of freezing cases should be closed as frequently as possible.Decrease the freezer units with an integrated compressor.

❶

❷

❸

❹

This department is characterized by higher energy consumption density than others; with a large amount of gas and electricity consumptions for cooking, and accordingly HVAC in contrast with its small area ratio. Due to wide use of indirect lighting and pendant lamps the lighting load is larger in proportion to their illuminance level.

Food and drink service

Pilot flame of gas cookers should be shut off as soon as it becomes unnecessary. Air orifices should be regulated to allow perfect combustion with proper heat.Increase/decrease the air volumes of exhaust fans and outside-air processing unit according to consumption of gas to minimize electricity consumption.Remove food leftovers before washing to reduce water/hot water supply consumption.The refrigerators/freezers for food storage be managed to minimize access frequency and time.Water, gas, and electric energy consumption should be measured per branch store to check the amount of their usage.A central monitoring system should be developed so that it detects an individual air-conditioning unit forgotten to be turned off, if any.Maintenance for facilities and equipment, including air-conditioning units and chillers, at different branch stores should not be managed separately by each store, but entirely by the store operator, following establishment and implementation of a maintenance standard.

❶

❷

❸❹

❺

❻

❼

Lights for showcases should be turned off after shop hours.The condenser tubes should be cleaned periodically.Preventive measures against short circuit of outdoor condensing units should be taken in order to mitigate degradation of their condensation capacity.Adopt showcases with air curtains and an energy-saving type.Arrangement of lamps inside in showcases should be changed to single row (single-row and double-row lamps should not have a much difference in visual effect).Installation of multi-chillers and hot gas defrosting system should be considered.Freezers and refrigerators should be placed next to each other whenever possible so that less area of their walls is exposed.Separate refrigerators according to cooling temperature range.For open-type showcases which do not require very low temperature, such as for fruits and veritable or dairy products, adoption of off-cycle defrosting system should be considered.

❶❷❸

❹❺

❻

❼

❽❾

Energy consumptions required by hot-water supply and cooking in food department (MJ/year)= a x food sales floor area m2 (a= 4,500 (maximum), 3,000 (median), 1,000 (minimum))

Freezing/refrigerating load of food sales departmentin department stores (kWh/m2) = 435 kWh/m2/year

Food chiller

4 5 6 7 8 9 1020

30

40

50

60

11 121 2 3Month of the year

Average floor area of fresh food(perishable food) sales section (m2)

Department store (average of two stores) 2,410General merchandise store (average of five stores) 2,850

kWh/㎡Department storeGeneral merchandise store


Ene

rgy

cons

erva

tion

mea

sure

sfo

r fr

eeze

rs a

nd r

efri

gera

tors

Freezing/refrigerating load of food sales departmentin general merchandise store (kWh/m2) = 504 kWh/m2/year

9

The following are energy conservation measures for the equipments (machines, lights, etc.) installed at commercial facilities.

5 Energy Conservation Measuresfor Different Installations andEquipment at Commercial Facilities

1. Energy conservation measures for heat source equipment

Quantity control of equipment should be adopted.VAV (variable air volume) system should be adopted.VWV (variable water volume) system should be adopted.Chilled-water conveyance system with large temperature difference should be implemented.Inspection and improvement should be made on insulating performance of ducts, piping, and other parts.An inverter device should be installed to chilled water pumps. And grasp the a total chilled water flow and set a proper frequency according to the required flowThree-way valves of chilled water system in air handling unit (AHU) should be replaced with two-way valves so that amount of circulated chilled water is reduced and, thus, power for water conveyance is reduced accordingly.In an establishment with a heat storage tank such as for chilled water storage, a semi-closed chilled water system with a plate-type heat exchangers and other devices should be adopted to reduce energy consumption of chilled water pumps.

❶❷❸❹❺❻

❼

❽

Energy conservation measures for heat-conveying(fans, pumps, piping) equipment

Total heat exchanger with outdoor air intake should be installed.Optimized outdoor-air intake in accordance with indoor CO2 concentration level should be achieved through some measures such as adoption of outsider cooling during winter and intermediate seasons.A patterned outside air-intake control based on the number of customers in the building should be adopted to allow only minimum necessary amount of air is taken into the building.Ventilation for parking space should be controlled by a CO sensor device.Inverter device should be installed for further energy conserving operations.An evaporation unit should be installed where their piping for coolant can be as short as possible and be arranged as straight as possible.If there are any walls or obstacles near the outdoor condensing units, a proper space between them should be kept. Also the units should be installed where they would not be exposed to radiation heat from sunlight or other types of heat sources.Anemostats and blind-shaped openings for air-conditioning or ventilation should be properly maintained so that outlets and inlets of rooms would not be blocked.Wind direction control device of air outlet, if any, should be adjusted so that the cooled air is blown in horizontal direction and the warm air is blown to downward direction. Effective and efficient operations with such measure could eliminate temperature differences between the room air in upper and lower layers.Direct entry of outdoor heated (or cold) air into the store should be prevented by way of installing air-break room or air curtains at the doorway of the store.Improved heat insulation measures should be added to walls, roof, and glass windows of the building.Cleaning of ducts, inspection for leakage, and appropriate repair should be made regularly.Filters and coils of air-conditioning units should be cleaned frequently.Maintenance for clogged filter alarm (manometer) should be made properly.Heat exchangers should be cleaned regularly.When operation of air-conditioning units is stopped for a long period, such as during off-season, the main power switch should be turned “OFF”.

❶❷

❸

❹❺❻

❼

❽

❾

10

111213141516

3. Energy conservation measures for HVAC equipment


Required capacity of equipment, such as boilers, chillers, chilled/hot water generators, should be divided into several units.Thermal insulation of bodies of boilers, steam headers, and valves should be enhanced.Replacement of centrifugal (turbo) chillers using specified CFCs with the ones using CFC alternatives should be considered, striving for improved coefficient of performance (COP) and reduced environmental impact.Inspections and preventive measures should be taken to see outdoor condensing units for short-circuited.

❶

❷❸

❹

2.

10

Measures such as adopting lighting control system, dividing lighting switches into smaller partitions, and turn off the area unnecessary and to reduce lighting hours before/after store hours.Installation of occupancy sensors in to the hallways of backyard and locker rooms should be considered.Daylight should be utilized for lighting.Lighting reflectors or shades should be installed to lighting fixtures.Lighting fixtures should be cleaned periodically.Colors of ceilings, walls, and floors should be changed to lighter tone with higher reflection rate.Lighting fixtures with high efficiency (e.g. inverter-controlled lights) device should be installed.More efficient lighting fixtures with higher light reflection and transmission should be installed.Fluorescent lamps should be replaced periodically.

❶

❷❸❹❺❻❼❽❾

4. Energy conservation measures for lighting equipment

Water-saving equipment should be installed.Water reservoirs level should be controlled to prevent frequent on/off of pumps for discharge sewage water, general service water, spring water, or rainwater.Installation of facilities and equipment which use recycled wastewater or well water should be considered.Leakage due to degraded packing of water taps should be prevented.Capacity of water lifting pump should be checked to see if it is appropriate. If it turns out to be too high, installation of inverter device should be considered. Improvement of the pump to the unit with appropriate capacity should also be considered when replacement is needed, striving for reduction of peak power.If a large difference between designed inflow rate and actual rate is found in recycled wastewater facilities, sewage treatment tank (abatement system), etc., it could cause excess operation of blowers and others, leading to higher DO (dissolved oxygen) level and excessive aeration. To solve the problem, measures to reduce aeration power, such as intermittent operations, should be sought.

❶❷

❸

❹❺

❻

Electric transformers should be replaced with the higher efficiency transformer in order to reduce a total loss. Replacement or improvement should be made starting from older equipment or equipment with lower annual load factor, so that higher improvement effect can be expected.Unbalanced load per bank should be addressed.In order to maintain proper indoor temperature, a control method for air-conditioning or ventilation of electric room should be changed from a timer-controlled to thermostatic controlled. The temperature setting should be around 35℃.Energy conservation measures and data analysis through implementation of building and energy management system (BEMS) and reconstruction of measurement and control functions should be promoted.

❶

❷❸

❹

Comparison of illuminance between general merchandise stores and department stores

Although department stores and general merchandise stores have similar level of illuminance, there is a significant difference between their electric consumptions. It is assumed that the gap is attributable to the difference in the ratio of used incandescent lamps.

0

20

40

60

80

100

120

1,304 1,340

1,686

1,0011000

1500

2000

500

0

1,053

Departmentstore - food

sales

Departmenstore -

first floor

Departmentstore -

commoditysales

Generalmerchandisestore - food

sales

Generalmerchandise

store -commodity

sales

Ｗ/㎡（lx）

Illuminance


Energy conservation measures for water supply/drainage and sanitation facilities and equipment5.

Energy conservation measures for electric powerreceiving and transforming equipment6.

11

A modification was made to have different time settings for starting air-conditioning units to precool or warm up the store before its opening at 10:00 am in different seasons. It was found that, during the seasons with moderate climate, the air-conditioning operation could be started 15 minutes later than during summer and winter, and therefore such delayed operation would require less energy consumption. Assuming that 26 units in the store are operated following the new rule, annual energy conservation for 6,672 kWh in electricity and 24,000 MJ of heat quantity (regional cooling) could be achieved.

6 Successful Cases of Energy ConservationMeasures of Commercial Facilities (1)Successful energy conservation measure at department store - 1

Data on air-conditioning operations on September 22, 2007

Data on air-conditioning operations on October 12, 2007

◆ Calculation of electricity reduction

●On September 22, following the start of air-conditioning operation, temperature of circulated air was raised to the set temperature (25℃) at 9:40.

●On October 12, the set temperature was ach ieved a t 9 :30 , o r 10 minutes ear l ier, a l though the air-conditioning operation started at the same time as September 22.

●In October, the set temperature can be achieved without any problem e v e n t h o u g h t h e s t a r t o f a i r -cond i t ion ing opera t ion i s delayed by 10 minutes or longer compared to September.

●It was found out that the precooling time could be shortened for about 15 minutes during winter and other seasons with moderate climate.

Circulated air temperature [℃] Outdoor air temperature [℃]

Air-conditioning operation [Hz] Chilled-water valve opening [%]

Circulated air temperature [℃] Outdoor air temperature [℃]

Air-conditioning operation [Hz] Chilled-water valve opening [%]

0

5

10

15

20

25

30

35

0

10

20

30

40

50

60

70

Precooling started at:

Precooling started at:

The set temperature was achieved at:

To minimizing

7:00 8:00 9:00 9:30 9:40 10:00 11:00 12:00

7:00 8:00 9:00 9:30 9:40 10:00 11:00 12:000

5

10

15

20

25

30

35

0

10

20

30

40

50

60

70

9:10

9:40

9:109:10

9:40


Electricity for air-conditioning equipment (26 units) 178kW x 1/4H (15 mins) x 5 months x 30 days = 6,672kWh

Tem

pera

ture

[℃]

Tem

pera

ture

[℃]

Air-

cond

ition

ing

freq

uenc

y [H

z]/

chill

ed-w

ater

val

ve o

peni

ng [%

]A

ir-co

nditi

onin

g op

erat

ion/

chill

ed-w

ater

valv

e op

enin

g [%

]Precooling

time

Precoolingtime

Unnecessary precooling timeUnnecessary precooling time

Unnecessary precooling timeUnnecessary precooling time

Store opened at 10:00

Store opened at 10:00

The set temperature was achieved at:

12

Successful Cases of Energy ConservationMeasures of Commercial Facilities (2)

(1) Heat source (for cooling) of individual water-cooling heat pump packages was operated and regulated to maintain its water temperature at or above 25℃ throughout the year. However, by lowering the temperature to 15℃, which is the minimum temperature guaranteed by its manufacturer, during winter and the following season with moderate climate (from November to April), an energy conservation was achieved.

Successful energy conservation measure at department store - 2

Impact by the changed temperature setting of heat source

Cooling-water temperature (temperature settings from 28℃ to 18℃)

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

8,000

*Note: Thermal load of the air-conditioning was considered to be the same due to the fact that difference in outdoor air temperatures before and after implementing the measure was within 1℃.

11% energysaving wasachieved

0.05.010.015.020.025.030.035.0

temperature setting at 28℃temperature setting at 18℃

Nov. 18th 20th 22nd 24th

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

PAC electricity on the 2nd floor (28℃) PAC electricity on the 2nd floor (18℃)

Nov. 18th 20th 22nd 24th

Cooling water temperatures and electricconsumption by individual PAC

System diagram of individual water-coolingheat pump package

11% energy saving was achieved on the 2nd and 3rd floors.Only low impact was given on the 1st and 4th floors since heating and cooling were required on those floors.

Cooling tower

Cooling water pumpHot waterboiler

29 units onthe 4th floor

30 units onthe 3rd floor

29 units onthe 2rd floor

34 units onthe 1st floor

8 units 6 units 6 units 9 units





Ele

ctric

con

sum

ptio

n (k

w/h

)

Coo

ling

wat

er te

mpe

ratu

re (℃

)El

ectri

c co

nsum

ptio

n (k

W)

PCelectricity

for 1st floor

PCelectricity

for 2nd floor

PCelectricity

for 3rd floor

PCelectricity

for 4th floor

Electricityfor cooling

tower

Heat source water temperature: 25℃Heat source water temperature: 15℃

11% energy saving can be achievedby lowering the temperature setting

of heat source water by 10℃

13

Energy conservation was achieved by raising temperature setting, by 2℃, for chilled water at an outlet of a centrifugal (turbo) chiller, which is heat source equipment for air-conditioning units, during winter and other seasons with moderate climate.

Successful Cases of Energy ConservationMeasures of Commercial Facilities (3)Successful energy conservation measure at department store - 3

●Energy consumption performance was compared before and after changing temperature setting for chilled water at an outlet of the centrifugal chiller from 6.5 to 8.5℃. The following graph illustrates changes in COP of the chillers when load factor varied between 20 and 100% at 6.5 and 8.5℃ of temperature setting. Actual temperature range for the 6.5℃ setting was between 6.4 and 7.6℃, and for the 8.5℃ setting was between 8.4 and 9.4℃.

Conditions

●As shown in the upper-left graph, the change of the temperature setting of chilled water at an outlet from 6.5 to 8.5℃ has improved COP of the centrifugal chiller at 80% load from 5.27 to 5.69, demonstrating a 8% increase.

●During winter and other seasons with moderate climate, this measure could a c h i e v e r e d u c t i o n o f p o w e r c o n s u m p t i o n by h e a t s o u r c e equipment for cooling.

●Only the primary pump is used to send the chi l led water, wi thout requiring additional heat-conveying power.

Results

●Only the data which satisfied the following conditions were selected and used for the comparison.

●Cooling water temperature: between 25.7 and 26.3℃●Load factor of chiller: between 20

and 100%

Conditions for data selection

y=ー0.0007x2+0.1116x+1.2434R2 =0.8845

y=ー0.0007x2+0.1112x+0.8492R2 =0.9362

0

1

2

3

4

5

6

7

0 10 20 30 40 50 60 70 80 90 100

Load factor of chillers

COP

（ー）

Chilled water temperature at outlet: 7℃Chilled water temperature at outlet: 9℃Regression (chilled water temperature at outlet: 7℃)Regression (chilled water temperature at outlet: 9℃)

6

7

8

9

10

11

12

13

14

0 10 20 30 40 50 60 70 80 90 100Load factor of chillers (%)

Chilled water temperature at outlet: 6.5℃Chilled water temperature at outlet: 8.5℃

Improved by 8%

Chilled watertemperature at outlet

8.5℃

6.5℃

6


Chi

lled

wat

er te

mpe

ratu

re (℃

)

14

Effective Tools and Techniques forPromoting Energy Conservation byImproved Operation

7ECCJ provides tools and techniques for further energy conservation useful for improving operations of large-scale buildings for business use without charge.The three tools and techniques are:

Combined use of the above three tools helps your making smoother energy conservation activities throughout the necessary steps for the activities; analysis on operation status and conditions, selection of improvement method, estimation of its effectiveness, and implementation of the measure.

How to obtain more detailed information on energyconservation of buildings for business use

ECCJ has a website to provide various kind of information on energyconservation of buildings.

The site includes:●inputs from actual users of tools (e.g. ESUM

and EAST) useful for enhancing your energy conservation activities for buildings;●various forums for different types of facilities

(e.g. office buildings, commercial facilities, hotels, and hospitals), which serve as an information exchange forum among members; and●invitations to seminars and lecture classes

which provides information on successful cases of improved energy conservation of buildings for business use and examples of effective use of various tools as well as materials for those seminars and lectures

http://eccj06.eccj.or.jp/bldg/index.phpURL

Open space forenergy

conservationin buildings

Persons in chargeof energy

conservationpromotion

Owners of buildingsfor business use

Persons in charge ofenergy facilitymanagement

ACCESS! Energy conservationbusiness operators


ESUM: Energy Specific Unit Management ToolESUM is computer software which estimates energy consumptions of a building and compares the consumptions before and after implementing an energy conservation measure to demonstrate the energy reduction effect.

❶

TuBE: Tuning of Building Systems for Energy ConservationTuBE is a document which defines how to select and carry out operational improvement actions among various energy conservation measures.

❷

EAST: Energy Analysis Support ToolEAST is computer software which compiles operation process data of air-conditioning units and heat source equipment and make a graphic presentation of the trends to help you analyze their operation conditions.

❸

Internet URL http://www.eccj.or.jp

3-19-9, Hatchobori, Chuo-ku, Tokyo, 104-0032 JapanTel: 81-3-5543-3018 Fax: 81-3-5543-3022

■ Head Office :

Copyright (C) The Energy Conservation Center, Japan 2009 All rights reserved

This is translated from the original Japanese document.For precise information and nuances, please refer to the original.

The Energy Conservation Center, Japan

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