Energy Conservation ofCommercial Facilities(Department Stores, General Merchandise Stores, and Shopping Centers)
Major points, measures, and successful cases of energy
conservation of commercial facilities

The Energy Conservation Center, Japan

Introduction
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 havebeen significantly growing especially in civilian business sectors andenhancement of drastic measures has become an urgent need.
This brochure is intended for owners of commercial facilities andpersons in charge of energy conservation promotion or energy facility
management, explaining the points, measures and the caseexamples of energy conservation based on our investigation data. We
h o p e t h a t yo u w i l l f i n d t h e i n fo r m a t i o n t a k i n g a c c o u n t o fcharacteristics in energy consumption particularly seen in operationsof commercial facilities helpful for your activities toward better energy
conservation practices.

C O N

1

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 Departments…………… 7of Commercial Facilities

5

Energy Conservation Measures for Different Installations and………… 9Equipment at Commercial Facilities

6

Successful Cases of Energy Conservation Measures of………………11
Commercial Facilities

7

Effective Tools and Techniques for Promoting Energy…………………14
Conservation by Improved Operation

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

1

Characteristics of Energy
Consumption at Commercial Facilities
The following graphs show the characteristics of energy consumption at largecommercial buildings in the size of designated energy management factories
located in the middle part of the county (between Tokyo metropolitan area andKansai metropolitan area), including 39 department stores, 12 general merchandise
stores, and 15 shopping centers.
The distribution of total floor space ofsurveyed buildings
No of buildings
20

15

10

5

0

Energy consumption by target facilities
percategory of business

2

4

6

8

10
12
14
16
18
20
Total floor area (unit: ten thousand m2)

Energy consumption trend of
typical facilities from each category
MJ/m2/month

TJ/year
Department store

General merchandise store

Shopping center

500

1000
900

400

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

800
700

Department store
300
Shopping center

600

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

500

200

General merchandise store

400
300

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

100

10
15
20
Total floor area (unit: ten thousand m2)

0

200
100

0

5

Energy intensity of different categories
of business

4

5

6

7

8

10 11 12 1
2
3Month of the year

The proportion of heat (fuel)and electricity consumption

Offices

Electricity

HotelsHeat (fuel)Offices

Hospitals
Department stores
Department stores excluding
car parking space
General merchandise
storesGeneral merchandise storesexcluding car parking space
Shopping centers
Shopping centers excluding
car parking space

9

HotelsHospitals
Department stores
General merchandise
stores
Shopping centers
0

1000

2000

3000

4000
MJ/m2/year

0

20

40

60

80

100
％

2

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

2

Energy Consumption Structure ofCommercial Facilities
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 toolfor energy specific unit management (computer software to estimate energy intensity
and their breakdowns) for free.

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

Shopping Average of allcentercategories

Number of facilities

39

12

15

（66）

Average (MJ/m2/year)

4,123

3,140

3,452

3,572

Maximum (MJ/m2/year)

6,149

3,760

4,273

4,728

Median (MJ/m2/year)

3,842

3,017

3,428

3,429

Minimum (MJ/m2/year)

2,624

2,668

2,821

2,704

MJ/m /year2<66 stores, arranged in order of energy consumption>

7000
6000

Department store

General merchandise store

Shopping center

5000
4000
3000
2000
1000
0

Proportion of car parking space to total floor space of commercial facilities％
50

Average 7%

Average 29%

Average 38%

40
30
20
10
0

39 department stores3

12 general merchandise
stores15 shopping centersMajor points, measures, and successful cases of energy conservation of commercial facilities

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, andchillers 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
Chillers and refrigerators 5.1％

Chillers and refrigerators Others 5.4％

Others 5.4%

Chillers and refrigerators
10.4％
ELV･ESC 4.3%

Heat source

31.4％

Main

Ventilation, water supply/
drainage, and other6.6%

machineGeneralunitsmerchandise 29.5％
stores
58,000㎡

Motive power

10.9％

Auxiliary
machine
units
1.9％

Air
6.9％

Lighting
22.0％

Electricaloutlets
5.8％

Water
0.5％

Heat
distribution

7.4％

Lighting andelectrical outlets

Hot water supply
and cooking
6.7％

27.8％

Sections behind the shop front
Commodity sales

26.2％

Cultural andleisure services

9.9％

Food anddrink services

14.6％

Food sales

34.3％

Commodity
sales

31.0％

Car parking
space

43.1％

Food sales

5.1％

Food anddrink services

2.4％

Sections behindthe shop front

15.2％

Cultural andleisure services

3.2％

Shares of floor area fordifferent departments

Shares of energy consumption
by different departments

6.7％

Car parking space 6.2％

9.8％

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

Others Others
2.2% 2.2%
Main machineunits
Heat source
22.8％

ELV･ESC
6.9%

30.6％

Electricaloutlets
11.0％

Ventilation,water supply/
drainage,and other
2.9%

Department
stores82,000㎡

Auxiliary
machine units
7.8％
Air 6.3％

Lighting
28.9％

Water
2.9％

Heat distribution

9.2％

Hot water supply
and cooking
3.2％Lighting andelectrical outlets

39.9％

Hot water supply and cooking

8.8％

Chillers and refrigerators
5.1％

Motive power

Shares of energy consumption
for different uses

10.4％

Hot water supply and cooking

3.2％

Sections behind the shop front
Cultural and
5.9％
Car parking space 0.2％
leisure services

2.3％

Food anddrink services

6.0％

Food sales

14.8％

Commodity sales

70.8％

Cultural andleisure services

1.9％

Car parking
space

Sections behindthe shop front

2.1％

21.2％

Food anddrink services

3.4％

Food sales

7.3％

Commodity sales

64.1％

Average business hours ofcommercial facilities

150%
140%
130%
120%

General merchandise stores A
General merchandise stores B
Department store A
Department store B

110%
100%

Category of business

Average annual
business hours

Department stores

3,633（362 days）

General merchandise
stores4,030（364 days）

Shopping centers

4,320（363 days）

90%
80%
70%

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

4

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

3

Energy Conservation Measures at
Commercial Facilities
The following are energy conservation measures which are often implemented incommercial facilities.
Their adoption rates vary depending on type of business.

Air conditioning

Improvement of various functions of building energy management system (BEMS)●Stop outside air intake during warm-up operation●Control outside air intake by CO2 concentration level●Calculation and summarization of(800 to 990 ppm)

●Outside air cooling●Heat recovery using total heat exchanger●Intermittent operation ofenergy consumption data
●Scheduled operations●Monitoring of operations conditions●Management of indoor air quality

air-conditioning units●Control of consumed energy● Measurements of electricity foreach feeder or transformer●Installation of flowmeters,

calorimeters, and thermometers

Reduction of power required to operate fans

●Turning off air-conditioning units

before closing time

●Adoption of high-efficiency fans
●VAV (variable air volume) control● Control of revolution speed through installation ofControl outside air intake
by CO2 concentration level

inverter device to light duty fans

● Replacement motors with higher efficiency ones

Heat source

Utilization of natural energy

Chiller●Solar power generation●Solar heat water heater●Energy conservation and reduction ofenvironmental burden throughmodifying centrifugal (turbo) chillers
using specified chlorofluorocarbon(CFCs) to chiller units using CFC
alternatives● Divide required equipment capacity
into appropriate units● Change chilled-water temperature
setting at summer and at intermediateseasons

Boiler●Optimization of air ratio●Dividing required equipment capacity

into several units

EHP/GHP● Taking preventive measures against

short circuit of outdoor condensing
units●Reduce the length of coolant pipes(estimated energy conservation ratio: 5%)●Installation of energy-saving belts (estimated energy

conservation ratio; 3 to 4%)

Cooling tower● On/off control of cooling

tower fans

●Cleaning and replacementof fillers

Air-conditioningunits● Control of cooling water

concentration level● C o n s i d e ra t i o n o f f r e ecooling system

Reduction of thermal load from
windows, sashes, and glasses●Reduction of window

space Enhance insulation
and airtight sashes● Use of heat reflecting or
double-glazed glasses

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

Total heatexchanger

WC

WC

WC

WC

WC

Well water treatment system to produce drinking water

Elevators

WC

Excess exhaust air●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%)

Space for handling/
disposal of goods●Control (turning on and off) ventilation fans in elevator motor room

Central monitor
and disaster
control centerusing a thermostatic system

Indoor car parking space● C h a n g o f ve n t i l a t i o n fa n c o n t r o lmethod from a schedule-based to
CO-concentration level-based method●Dividing controllable lighting area into

smaller partitions

5

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

Air-conditioning
pump

Chiller

Electric room
Lifting pump

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

Adoption rate of energy conservation
techniques at commercial facilities

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

Automatic water faucet
Automatic power factor
regulator
Control on the number of heat source
equipment units in service
Inverter-controlled lighting

Department store

Outdoor air cooling

General merchandise store
Shopping center

Demand control system
Control on the number ofpumps in service
Inverter-control of pumps
Internal air isolation
control at starting
Device to drown out
toilet noises
High-efficient transformer

System for reducing
foamed polystyrene
volumeWell water treatment system
to produce drinking water
and/or general service water
Pollution abatement
system fordischarged water

Variable air volume (VAV)
control
Outdoor-air intake regulation

Aeration andagitation pump

Ventilated air regulation
Energy-saving belt

General merchandise store

Daylight sensor

Improvement ordevelopment of recycled
wastewater facility

Shopping center

High-efficiency motor

0Composting
system

Department store

Total heat exchanger

10

20

30

40

50

60

Prevention of unnecessary outdoor air
from entering into building

70

0

80％

10

20

30

40

50
％

Floor planning●Prevention of outdoor air entry at entrances and exits● Checking that a damper is closed when air-conditioning isturned off●Installation of airbrake room at door way●Maintaining room air pressure positive●Utilizing service space as a buffer area to insulate heat from exteriorwalls●Place the openings in the lee of the building●Phased arrangement of air-conditioning space

Indoor lighting●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

M

ELV
Restaurants

Food Showcases●Use of energy-conserving food showcases●Installation of night covers (insulation covers)● Eliminating use of showcases which

Shops

discharge heat indoors

Shops

Night cover

Reduction of electric distribution loss and power loss
●Modification of the system to shorter distribution route●Use of wires with thicker size

Shops

Electric power receiving and transforming● Improvement transformer to the high-efficiency one (total loss is

Shops

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

Shops

transformer in the latter system can be turned off.

Entrance●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

Shops

Shops

Installation of cogeneration system
Car parking
space● 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

6

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

4

Energy Conservation Measuresfor Different Departments ofCommercial Facilities
The following are energy conservation measures for different departments, which are
helpful for you to promote your energy conservation initiative.

Commodity Sales department
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.
Importantpoints forthe measures❶ Adopt air-break room at door way.
❷ Improved arrangement of lighting equipments with effective impact should be made sothat the number of incandescent lamps can be reduced. Utilization of daylight forlighting purpose around entrances and near windows should also be considered.
❸ Energy-saving lighting equipments with inverter device should be installed.
❹ Excess air cooling or heating should be avoided.
❺ Outside air cooling should be implemented during winter and intermediate seasons.
❻ 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.

Administrative 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 anenergy consumption structure similar to food and drink service department.
Importantpoints forthe measures❶ Since offices and the back yards have different operating hours for different purposes,

an individual air-conditioning should be adopted.

❷ Lighting area should be divided into smaller partitions to turn off lights whereverunnecessary.

❸ Temperature setting for air-conditioning should be at 20℃ during winter and 28℃during summer.

❹ Lighting equipments should be replaced to inverter type.
❺ Daylight should be utilized for lighting in the office. A motion sensor device should beinstalled to turn on/off lights for such as locker rooms, etc.

Car parking space
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 withsemi-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.
Importantpoints forthe measures

7❶ 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.
❷ A CO sensor device should be installed to control ventilation system based on thestandard CO level.
❸ Alert drivers to encourage to stop idling practice.
❹ Some improvements which could make driving speed slower should be added in thedrive ways in order to reduce exhaust gas emissions.

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

Food sales department
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 thanothers, 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.
Importantpoints forthe measures

Food chiller❶ 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 avoided❷ Foods should be kept at proper temperature, avoiding excess cooling of open-type

showcases.

❸ L-leakage of the chill after closing the store should be prevented using night covers orother measures. Glass doors of freezing cases should be closed as frequently as
possible.
❹ Decrease the freezer units with an integrated compressor.

Energy conservation measures
for freezers and refrigerators

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))❶ Lights for showcases should be turned off after shop hours.
❷ The condenser tubes should be cleaned periodically.
❸ Preventive measures against shor t circuit of outdoor

kWh/㎡
60

Department store
General merchandise store

condensing units should be taken in order to mitigate
50
degradation of their condensation capacity.
❹ Adopt showcases with air curtains and an energy-saving type.
40❺ Arrangement of lamps inside in showcases should bechanged to single row (single-row and double-row lamps
Average floor area of fresh food30
(perishable food) sales section (m )should not have a much difference in visual effect).
Department store (average of two stores) 2,410❻ Installation of multi-chillers and hot gas defrosting system
General merchandise store (average of five stores) 2,850
20
should be considered.
1 2 3 4 5 6 7 8 9 10 11 12Month of the year
❼ Freezers and refrigerators should be placed next to eachother whenever possible so that less area of their walls is exposed.
❽ Separate refrigerators according to cooling temperature range.
❾ For open-type showcases which do not require very low temperature, such as for fruits andveritable or dairy products, adoption of off-cycle defrosting system should be considered.
2

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

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

Food and drink service
This department is characterized by higher energy consumption density than others; with a large amount ofgas 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 theirilluminance level.
Importantpoints forthe measures❶ 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.

❷ Increase/decrease the air volumes of exhaust fans and outside-air processing unit

according to consumption of gas to minimize electricity consumption.

❸ Remove food leftovers before washing to reduce water/hot water supply consumption.
❹ The refrigerators/freezers for food storage be managed to minimize access frequency

and time.

❺ Water, gas, and electric energy consumption should be measured per branch store tocheck the amount of their usage.

❻ A central monitoring system should be developed so that it detects an individual

air-conditioning unit forgotten to be turned off, if any.

❼ Maintenance for facilities and equipment, including air-conditioning units and chillers,

at different branch stores should not be managed separately by each store, but entirelyby the store operator, following establishment and implementation of a maintenancestandard.

8

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

5

Energy Conservation Measuresfor Different Installations andEquipment at Commercial Facilities
The following are energy conservation measures for the equipments (machines,
lights, etc.) installed at commercial facilities.

1. Energy conservation measures for heat source equipment❶ Required capacity of equipment, such as boilers, chillers, chilled/hot water generators, should be

divided into several units.

❷ Thermal insulation of bodies of boilers, steam headers, and valves should be enhanced.
❸ 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.
❹ Inspections and preventive measures should be taken to see outdoor condensing units for
short-circuited.

conservation measures for heat-conveying
2. Energy(fans, pumps, piping) equipment❶ Quantity control of equipment should be adopted.
❷ VAV (variable air volume) system should be adopted.
❸ VWV (variable water volume) system should be adopted.
❹ Chilled-water conveyance system with large temperature difference should be implemented.
❺ Inspection and improvement should be made on insulating performance of ducts, piping, and other parts.
❻ 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 flow

❼ Three-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 isreduced accordingly.
❽ In an establishment with a heat storage tank such as for chilled water storage, a semi-closed chilledwater system with a plate-type heat exchangers and other devices should be adopted to reduce energy
consumption of chilled water pumps.

3. Energy conservation measures for HVAC equipment❶ Total heat exchanger with outdoor air intake should be installed.
❷ 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.

❸ 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.

❹ Ventilation for parking space should be controlled by a CO sensor device.
❺ Inverter device should be installed for further energy conserving operations.
❻ An evaporation unit should be installed where their piping for coolant can be as short as possible and be

arranged as straight as possible.

❼ If there are any walls or obstacles near the outdoor condensing units, a proper space between them9should be kept. Also the units should be installed where they would not be exposed to radiation heat fromsunlight or other types of heat sources.
❽ 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.
❾ Wind direction control device of air outlet, if any, should be adjusted so that the cooled air is blown inhorizontal direction and the warm air is blown to downward direction. Effective and efficient operations withsuch measure could eliminate temperature differences between the room air in upper and lower layers.
❿ Direct entry of outdoor heated (or cold) air into the store should be prevented by way of installing air-breakroom or air curtains at the doorway of the store.
⓫ Improved heat insulation measures should be added to walls, roof, and glass windows of the building.
⓬ Cleaning of ducts, inspection for leakage, and appropriate repair should be made regularly.
⓭ Filters and coils of air-conditioning units should be cleaned frequently.
⓮ Maintenance for clogged filter alarm (manometer) should be made properly.
⓯ Heat exchangers should be cleaned regularly.
⓰ 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”.

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

4. Energy conservation measures for lighting equipment❶ 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.

❷ Installation of occupancy sensors in to the hallways of backyard and locker rooms should be considered.
❸ Daylight should be utilized for lighting.
❹ Lighting reflectors or shades should be installed to lighting fixtures.
❺ Lighting fixtures should be cleaned periodically.
❻ Colors of ceilings, walls, and floors should be changed to lighter tone with higher reflection rate.
❼ Lighting fixtures with high efficiency (e.g. inverter-controlled lights) device should be installed.
❽ More efficient lighting fixtures with higher light reflection and transmission should be installed.
❾ Fluorescent lamps should be replaced periodically.

conservation measures for water supply/
5. Energy
drainage and sanitation facilities and equipment❶ Water-saving equipment should be installed.
❷ Water reservoirs level should be controlled to prevent frequent on/off of pumps for discharge sewage

water, general service water, spring water, or rainwater.

❸ Installation of facilities and equipment which use recycled wastewater or well water should beconsidered.

❹ Leakage due to degraded packing of water taps should be prevented.
❺ 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 withappropriate capacity should also be considered when replacement is needed, striving for reduction ofpeak power.
❻ 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 theproblem, measures to reduce aeration power, such as intermittent operations, should be sought.

conservation measures for electric power
6. Energy
receiving and transforming equipment❶ 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 equipmentwith lower annual load factor, so that higher improvement effect can be expected.
❷ Unbalanced load per bank should be addressed.
❸ In order to maintain proper indoor temperature, a control method for air-conditioning or ventilation ofelectric room should be changed from a timer-controlled to thermostatic controlled. The temperature
setting should be around 35℃.
❹ Energy conservation measures and data analysis through implementation of building and energy
management system (BEMS) and reconstruction of measurement and control functions should bepromoted.

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

Ｗ/㎡
120

（lx）
2000
1,686

100
80

1,304

Illuminance

1,340
1,001

60

1,053

1500

1000

40
500

20
0

Department
GeneralDepartmen
store - food merchandise
store sales
store - food first floor
sales

GeneralDepartment
merchandise
store store commodity
commodity
sales
sales

0

10

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

6

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

A modification was made to have different time settings for starting air-conditioning units to precool orwarm up the store before its opening at 10:00 am in different seasons. It was found that, during theseasons with moderate climate, the air-conditioning operation could be started 15 minutes later thanduring 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.

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

Precoolingtime
Unnecessary precooling time
To minimizing

Temperature [℃]

35

70

30

60

25

50

20
15

40

Precooling started at:

9:10

30

10

The set temperature was achieved at:

5Store opened at 10:00

20

9:40

10

0

7:00

0

8:00

9:00 9:30 9:40 10:00

11:00

12:00

Circulated air temperature [℃]

Outdoor air temperature [℃]Air-conditioning operation [Hz]Chilled-water valve opening [%]Air-conditioning operation/chilled-water
valve opening [%]Data on air-conditioning operations on September 22, 2007

● On September 22, following thestart 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 achieved at 9:30, or 10
m i n u t e s e a r l i e r, a l t h o u g h t h e
air-conditioning operation started at
the same time as September 22.
●In October, the set temperature canbe achieved without any problem
even though the star t of
air-conditioning operation isdelayed by 10 minutes or longer
compared to September.

Data on air-conditioning operations on October 12, 2007
●It was found out that the precooling

Precooling
time
35

70

30

60

25

50

20
15

30

9:10

10 The set temperature was achieved at:
5
0

7:00

11

40
Precooling started at:

20

9:40

10

Store opened at 10:00

8:00

9:00 9:30 9:40 10:00

11:00

0

12:00

Circulated air temperature [℃]

Outdoor air temperature [℃]Air-conditioning operation [Hz]Chilled-water valve opening [%]Air-conditioning frequency [Hz]/chilled-water valve opening [%]Temperature [℃]

Unnecessary precooling time

time could be shortened for about
15 minutes during winter and otherseasons with moderate climate.

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

Successful Cases of Energy Conservation
Measures of Commercial Facilities (2)Successful energy conservation measure at department store - 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 thetemperature to 15℃, which is the minimum temperature guaranteed by its manufacturer, during winter andthe following season with moderate climate (from November to April), an energy conservation wasachieved.

Impact by the changed temperature setting of heat source
Heat source water temperature: 25℃
Heat source water temperature: 15℃

7,000
6,000
5,000
4,000

11% energy
saving wasachieved

3,000
2,000

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

1,000

PC
PC
PC
electricity
electricity electricity
for 1st floor for 2nd floor for 3rd floor

PC
Electricity
electricity for coolingfor 4th floor
tower

System diagram of individual water-coolingheat pump package

Cooling tower

29 units on
the 4th floor

8 units

6 units

6 units

9 units

30 units on
the 3rd floor

5 units

9 units

6 units

10 units

29 units on
the 2rd floor

6 units

7 units

5 units

11 units

34 units on
the 1st floor

6 units

9 units

Cooling water pump

9 units

Hot water
boiler10 units

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

0

35.0
30.0
25.0
20.0
15.0
10.0
5.0
0.0

Nov. 18th

20th

22nd

24th

temperature setting at 28℃
temperature setting at 18℃

11% energy saving can be achieved
by lowering the temperature settingof heat source water by 10℃

Cooling water temperatures and electric
consumption by individual PAC
Electric consumption (kW)Electric consumption (kw/h)

8,000

14.0
12.0
10.0
8.0
6.0
4.0
2.0
0.0

Nov. 18th

20th

22nd

24th

PAC electricity on the 2nd floor (28℃)
PAC electricity on the 2nd floor (18℃)*Note: Thermal load of the air-conditioning wasconsidered to be the same due to the fact thatdifference in outdoor air temperatures before andafter implementing the measure was within 1℃.

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

6

Successful Cases of Energy Conservation
Measures of Commercial Facilities (3)Successful energy conservation measure at department store - 3
Energy conservation was achieved by raising temperature setting, by 2℃, for chilledwater 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.

Conditions● 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℃.

Results7
y=ー0.0007x 2+0.1116x+1.2434
R2 =0.8845

6

Improved by 8%

5
COP

4

（ー）3

y=ー0.0007x 2+0.1112x+0.8492
R2 =0.9362

2

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℃)

1
0

0

10

20

30

40

50

60

70

80

90 100

Load factor of chillers●As shown in the upper-left graph, thechange of the temperature setting ofchilled water at an outlet from 6.5 to
8.5℃ has improved COP of thecentrifugal chiller at 80% load from
5.27 to 5.69, demonstrating a 8%
increase.
●During winter and other seasons withmoderate climate, this measure could
achieve reduction of power
consumption by heat source
equipment for cooling.
● Only the primary pump is used tos e n d t h e c h i l l e d wa t e r, w i t h o u trequiring additional heat-conveying
power.

14
Chilled water temperature at outlet: 6.5℃
Chilled water temperature at outlet: 8.5℃

Chilled water temperature (℃)

1312Conditions for data selection

11
Chilled watertemperature at outlet

10

8.5℃

9
8

6.5℃

7
6

following conditions were selected
and used for the comparison.
●Cooling water temperature: between

25.7 and 26.3℃
0

10

20

30

40

50

60

70

Load factor of chillers (%)

13● Only the data which satisfied the80

90 100● Load factor of chiller: between 20

and 100%

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

7

Effective Tools and Techniques for
Promoting Energy Conservation by
Improved Operation

ECCJ 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:
❶ ESUM: Energy Specific Unit Management Tool
ESUM is computer software which estimates energy consumptions of a building andcompares the consumptions before and after implementing an energy conservation measure
to demonstrate the energy reduction effect.
❷ TuBE: Tuning of Building Systems for Energy Conservation

TuBE is a document which defines how to select and carry out operational improvement
actions among various energy conservation measures.
❸ EAST: Energy Analysis Support Tool

EAST 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.
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 andconditions, selection of improvement method, estimation of its effectiveness, andimplementation of the measure.

How to obtain more detailed information on energy
conservation of buildings for business use
ECCJ has a website to provide various kind of information on energy
conservation 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 ofbuildings for business use and examples ofeffective use of various tools as well as
materials for those seminars and lectures
URL

Owners of buildings
for business use

Persons in chargeof energy
conservation
promotion

Persons in charge ofenergy facility
management

ACCESS! business operators

Energy conservation

Open space forenergyconservationin buildings

http://eccj06.eccj.or.jp/bldg/index.php
14

The Energy Conservation Center, Japan
Internet URL http://www.eccj.or.jp■ Head Office : 3- 19- 9, Hatchobori, Chuo-ku, Tokyo, 104- 0032 Japan

Tel: 81- 3- 5543- 3018

Fax: 81- 3- 5543- 3022

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

Copyright (C) The Energy Conservation Center, Japan 2009

All rights reserved