Final Report by Electric Refrigerator Evaluation Standards Subcommittee,
Energy Efficiency Standards Subcommittee of the Advisory Committee for
Natural Resources and Energy

The Electric Refrigerator Evaluation Standards Subcommittee had deliberations on judgment
standards for the manufacturers or importers (hereinafter referred to as “manufacturers”) concerning
performance improvement of electric refrigerators (including electric freezers andrefrigerator-freezers, hereinafter), and prepared an final summary report as below.
1. Evaluation of Current Standards
The weighted mean of energy consumption efficiency of electric refrigerators (including
electric refrigerator-freezers, hereinafter) whose target year was fiscal 2004 was decreased to290.3 kWh/year, which corresponds to improvement of 55.2% from the weighted mean of energy
consumption efficiency (647.3kWh/year) (of products shipped prior to 1998) before introductionof the Top Runner Standard. In addition, the improvement was even better than the estimates(449.7 kWh/year) and the assumed improvement rate (30.5%), when the Top Runner Standard wasthen achieved.
In addition, the weighted mean of energy consumption efficiency of electric freezers was
369.7 kWh/year, which corresponds to improvement of 29.6% from the weighted mean of energy
consumption efficiency (of products shipped in 1998) before introduction of the Top RunnerStandard. In addition, the improvement was even better than the estimates (404.7 kWh/year) andthe assumed improvement rate (22.9%), when the Top Runner Standard was then achieved.
With the above in mind, we can evaluate that as a result of efforts for energy conservation
by manufacturers, energy saving has progressed and thus the current standards based on the Top
Runner Program work effectively.
2. Target Scope [See Attachment 1]
This review shall apply to electric refrigerators stipulated as being covered by
JISC9801:2006 Household Refrigerating Appliances---Characteristics and test methods.
3. Items to be judgment standards for manufacturers(1) Target fiscal year [See Attachment 2]
It shall be the fiscal year 2010 .
(2) Target standard values [See Attachments 3 to 4]
With regard to electric refrigerators that manufacturers ship within Japan for the target
fiscal year, a weighted average of the energy consumption efficiency (annual energy
consumption) calculated in (3), by the volume of shipments for each manufacturer per category
in the table below shall not exceed the target standard value.

Category
A
B
C
D

Electric Refrigerators (Including Electric Refrigerator-freezers)
Number ofRated Internal
Calculation Formula ofCooling TypeDoors in Chiller
VolumeTarget Standard Value
SectionNatural convection－
E=0.844Vadj+155－
type
300L or less
E=0.774Vadj+220－
Forced circulationOne
door
E=0.302Vadj+343
typeOver 300L
Over one door
E=0.296Vadj+3741CategoryE
F
G

Cooling Type
Natural convection
type
Forced circulation
type

Electric Freezers
Number ofRated Internal
Doors in Chiller
VolumeSection－－
300L or lessOver 300L－

Calculation Formula ofTarget Standard Value
E=0.844Vadj+155
E=0.774Vadj+220
E=0.302Vadj+343

Notes (1) E: Energy consumption efficiency (kWh/year)(2 ) Vadj: Adjusted internal volume (unit: L)
1) For a refrigerator-freezer and a freezer whose freezing compartment is of three-star type,
Vadj shall be a numeric value obtained with the following formula:
Vadj= 2.20 x V (Rated internal volume of a freezing compartment) + V (Rated internal
volume of other than a freezing compartment)
2.20 = (22.4°C-(-18 °C))/(22.4 °C -4 °C) = 40.4/18.4
2) For a refrigerator-freezer and a freezer whose freezing compartment is of two-star type,
Vadj shall be a numeric value obtained with the following formula:
Vadj= 1.87 x V (Rated internal volume of a freezing compartment) + V (Rated internal
volume of other than a freezing compartment)
1.87 = (22.4 °C -(-12 °C))/(22.4 °C -4 °C) = 34.4/18.4
3) For a refrigerator-freezer and a freezer whose freezing compartment is of one-star type,
Vadj shall be a numeric value obtained with the following formula:
Vadj= 1.54 x V (Rated internal volume of a freezing compartment) + V (Rated internal
volume of other than a freezing compartment)
1.54 = (22.4 °C -(-6 °C))/(22.4°C -4 °C) = 28.4/18.4(For Your Reference)
Three-star type :Two-star type :One-star type :A freezing compartment whose average freezing load
temperature of which is –18 °C or lower
A freezing compartment whose average freezing load
temperature of which is –12 °C or lower
A freezing compartment whose average freezing load
temperature of which is –6 °C or lower2(3) Energy consumption efficiency measurement method [See Attachment 5]
The energy consumption efficiency of electric refrigerators shall be annual energy
consumption, and a measurement method shall be the method specified in JISC9801: 2006 (forthose with rated frequency of both 50 Hz and 60Hz, a larger value of those measured with 50Hz
and 60 Hz shall be taken). For a refrigerator-freezer whose freezing compartment can beswitched to cooling mode of a chiller, it shall be numeric values measured in respective modes,
whichever is larger.
(4) Display items and others
Items to be displayed for electric refrigerators shall follow the provisions defined in theHousehold Good Quality Labeling Law, while items to be displayed for electric freezers shallfollow the law concerning the Rational Use of Energy. Items concerning energy saving shall be
as follows:
1) Display items shall be as follows:a) Product name and model nameb) Rated internal volumec) Energy consumption efficiencyd) Outside dimensione) Manufacturer’s name2) Compliance items
The compliance items shall be as current specification.
4. Proposals for energy saving(1) Actions of users
1) Through effective use of information such as “energy-saving labels”, etc, users shall attempt
to not only select an electric refrigerator with excellent energy consumption efficiency but
also reduce energy by using an electric refrigerator appropriately and efficiently. (Retailers,manufacturers, and the government shall actively strive to offer information that contributes
to such actions of users.)2) In particular, users shall try to save energy by giving consideration to overloading of food,etc., or a place of installation of an electric refrigerator, etc.
(2) Actions of retailers
1) Retailers shall not only try to sell electric refrigerators with excellent energy consumption
efficiency, but also offer appropriate information to users so that they can select electric
refrigerators with excellent energy consumption efficiency.
In addition, in using
energy-saving labels, retailers shall carefully display the labels in a manner that users caneasily understand and get no false impression, by, for example, showing conditions forcalculating energy consumption efficiency.

3(3) Actions of manufacturers
1) Manufactures shall promote technological development toward energy conservation ofelectric refrigerators and attempt to develop products with excellent energy consumption
efficiency.
2) From the viewpoint of promoting the spread of electric refrigerators with excellent energy
consumption efficiency, manufacturers shall attempt to provide appropriate information to
encourage users to select electric refrigerators with excellent energy consumption efficiency,
by displaying “energy-saving labels” in a catalogue, etc. In utilizing the energy-saving
labels, manufacturers shall carefully display them in a manner that users can easily
understand and get no false impression, by, for example, showing conditions for calculatingenergy consumption efficiency.
3) Manufacturers shall endeavor not to develop energy saving technologies suitable for ameasuring method of energy consumption efficiency but to develop energy saving
technologies suitable for the actual status of the usage of users.
4) Manufacturers shall strive to promptly establish a measurement method of energy
consumption of electric refrigerators for commercial use.
(4) Actions of Government
1) From the viewpoint of promoting the spread of electric refrigerators with excellent energy
consumption efficiency, the government shall attempt to take necessary action such as the
spread and enlightenment activities, in order to promote actions of users and manufacturers.
It shall also attempt to take such necessary action as spread or enlightenment activities forapproach to energy conservation through a place of installation or a method of use of electric
refrigerators, etc.
2) The government shall periodically and continuously check implementation of the display
items by manufacturers and attempt at appropriate operation of the law so that information
on energy consumption efficiency can be provided to users in correct and easily
understandable manner.
3) The energy-saving standard based on the Top Runner Program is a very effective approachto energy saving of products. Therefore, the government shall make efforts to spread it not
only domestically but also internationally, by taking appropriate opportunities.
4) The government shall continue to review propriety of addition of commercial electric
refrigerators, as a target product of the Top Runner Standard.

4

Attachment 1
Target Scope
1. Electric Refrigerators
The present judgment standards, etc. shall apply to electric refrigerators specified as being
covered by JISC9801.
In addition, the following shall be excluded.
1) Electric refrigerators of absorption type
They are used for specific purposes such as use in hotels, etc. Since there is noestablished measuring method of energy consumption efficiency of this kind and the production
volume is extremely small, they shall be excluded.
*Volume of imports (in Fiscal 2004): Approximately 9,000 units<<Mechanism of Absorption Type>>

Condenser(Heat release)

Evaporator(Heat absorption)

Concentrated
ammonia gas

Ammonia liquid

Heater

Diluted ammonia

5

Absorption type refrigerator that cools downwhen heated
・A heat source may be gas, electricity, or
anything.
・A refrigerant is ammonia.
・An absorber is water.
・The mechanism is that heat absorption ofammonia liquefied in a condenser cools
down the periphery when it vaporizes inan evaporator.

2) Electric refrigerators of Peltier method
They are used for specific purposes such as use in hotels, etc. Since there is noestablished measuring method of energy consumption efficiency of this kind and the production
volume is extremely small, they shall be excluded.
*Domestic production (in Fiscal 2004): Approximately 13,000 units<<Workings of Peltier Type>>[Structure](Peltier element)
COLD side (Inside)

HOT side (outside)

Manifold

Manifold

Fan motor

Fan motor

Pump

Pump

3) Vehicle-mounted electric refrigerators
Since there is no established measuring method of energy consumption efficiency andproduction volume is extremely small, they shall be excluded. Note that the following volume
of domestic production is that of electric refrigerators and freezers.
*Domestic production (in Fiscal 2004): Approximately 5,000 units
4) Commercial Electric Refrigerators
Approximately 150,000 units of commercial electric refrigerators were manufactured in
2004 (according to statistics published by Japan Refrigeration and Air Conditioning Industry
Association). However, they are typical products with small productions as well as large
variations; therefore, they are often made-to-order and applied to various purposes. Due tosuch circumstances, at the current moment, no measuring method such asmeasurement/computation of energy consumption has been established. Nevertheless, since
discussion on the measuring method has been under way in Japan Refrigeration and Air
Conditioning Industry Association, we shall separately consider the possibility of including
them as a target product as soon as a measuring method is developed.

6

2. Electric Freezers
The present judgment standards, etc. shall apply to electric freezers specified as being
covered by JISC9801. The followings shall be excluded.
1) Vehicle-Mounted Electric Freezers
Since there is no established measuring method of energy consumption efficiency andproduction volume is extremely small, they shall be excluded. Note that the following volume
of domestic production is that of electric refrigerators and freezers.
*Domestic production (in the fiscal year 2004): Approximately 5,000 units
2) Commercial Electric Freezers
Approximately 30,000 units of commercial electric freezers were manufactured in thefiscal year 2004 (according to statistics published by the Japan Refrigeration and Air
Conditioning Industry Association).
However, they are typical products with small
productions as well as large variations; therefore, they are often made-to-order and applied tovarious purposes. Due to such circumstances, at the current moment, no measuring method
such as measurement/computation of energy consumption has been established. Nevertheless,since discussion on the measuring method has been under way in Japan Refrigeration and Air
Conditioning Industry Association, we shall separately consider the possibility of including
them as a target product as soon as a measuring method is developed.

7

Attachment 2
Target Fiscal Year of Electric Refrigerators, etc.
1. In general, a considerable improvement in energy consumption efficiency of electric
refrigerators is made when a model change takes place, and a typical development period of
new products of electric refrigerators is approximately 2 to 3 years. For this reason,
consideration should be given so that manufacturers can take about 1 or 2 opportunities ofbringing out new models before the next target fiscal year.
With the above in mind, it is appropriate to set the next target fiscal year of electric
refrigerators to the fiscal year 2010.
2. In addition, it is expected that the improvement rate of energy consumption efficiency in thetarget fiscal year will be approximately 21.0% for electric refrigerators and approximately
12.7% for electric freezers, based on the assumption that there will be no change from current
volume of shipments and composition of each category (results of the fiscal year 2005).
<Overview of Estimation: Electric Refrigerators>(1) Energy consumption efficiency calculated from values of actual achievements of electric
refrigerators shipped in the fiscal year 2005:
Approximately 572 kWh/year(2) Energy consumption efficiency estimated from the target standard value of electric
refrigerators to be shipped in the target fiscal year:
Approximately 452 kWh/year(3) Improvement rate of energy consumption efficiency

５７２－４５２
× １００ ＝
５７２

Approximately 21.0 %<Overview of Estimation: Electric Freezers>(1) Energy consumption efficiency calculated from values of actual achievements ofelectric freezers shipped in the fiscal 2005:
Approximately 482 kWh/year(2)
Energy consumption efficiency estimated from the target standard value of electricfreezers to be shipped in the target fiscal year:
Approximately 421 kWh/year(3) Improvement rate of energy consumption efficiency

４８２－４２１
× １００ ＝
４８２

Approximately 12.7 %8

Attachment 3
Classification of Electric Refrigerators
1. Basic Idea
Under the current criteria, electric refrigerators are classified based on the following:
1) Classification by storage
2) Classification by cooling type3) Classification by use of specified technology (inverter technology and vacuum insulationmaterial)
The electric refrigerators shall be classified as shown below:
Table 1: Current Classification of Electric Refrigerators
Storage

Cooling TypeUse of Specified Technology

Electric
Refrigerators

Cold air-natural convection type－

Cold air-forced circulation type－

Cold air-natural convection type－

RefrigeratorFreezers

Cold air-forced circulation type

Using specified technology
Without

specified technology

Electric freezers shall be classified as shown below:
Table 2: Current Classification of Electric Freezers
StorageFreezers

Cooling TypeUse of Specified Technology

Cold air-natural convection type－

Cold air-forced circulation type－

Under the new standard, classification shall be made, considering the following:
1) A distinction shall be made between refrigerators (including refrigerator-freezers) and freezers,
because they have a different storage configuration and are also considered being different inJapan Standard Commodity Classification (JSCC) (revised in June 1990, Ministry of Internal
Affairs and Communications).
2) As a measuring method of energy consumption efficiency specified in JISC 9801 partly differs,
classification shall be made for cooling type.
3) In recent years, in order to improve energy saving performance, inverter technology andvacuum insulation materials have been widely introduced. Classification shall be made,taking this into consideration.

94) As various devices such as layout of a freezing compartment and a vegetable drawer, number ofchiller doors, and etc. have been made in view of consumers’ needs, and thus configurations ofelectric refrigerators have become diversified, classification of them shall also be considered.
2. Specific Classification Method(1) Classification by Storage
A distinction shall be made between refrigerators and freezers, because they have a
different storage configuration and are also considered being different in Japan Standard
Commodity Classification (JSCC) (revised in June 1990, Ministry of Internal Affairs andCommunications).
(2) Classification by Cooling TypeA measuring method of energy consumption efficiency of electric refrigerators is specified
in JIS 9801. However, electric refrigerators of natural convection type and those of forced
circulation type have different measurement conditions such as regarding opening/closing ofdoors, etc. Thus, it is not possible to simply compare their respective energy consumption
efficiency, and they shall be separated.
(3) Classification by Rated Internal Volume
Under the current classification, electric refrigerators are classified by use of specified
technology (inverter technology and vacuum insulation material). However, as for electric
refrigerators having rated internal volume of over 300L, many of them have incorporated thespecified technology to improve energy saving performance. As a result, it is no longer
exceptional.
Nevertheless, the specified technology has not been introduced to electric refrigerators
having rated internal volume of 300L or smaller still yet, because increased price will accompany.
For instance, an attempt to introduce the inverter technology into an electric refrigerator having
rated internal volume of 300L or smaller would result in a price increase of about 17,000 yen(according to the survey by the Japan Electrical Manufacturers’ Association). Then, thepossibility is high that the increased price cannot be recovered by means of lowering the running
cost.
Therefore, possible effect of the introduction of the specified technology taken into
consideration, classification by rated internal volume of electric refrigerators shall be made withthe rated internal volume of 300L as a border, while no classification by presence/absence of thespecified technology shall be made.
<<For your reference>>
A price increase of 17,000 yen can be converted into energy consumption, as follows:
17,000 (yen) ÷ 22 (yen/kWh) = 772.7 (kWh)Assuming that electric refrigerators will be used for 10 years, we have to cut down annual
energy consumption by approximately 77.3 kWh. If energy saving effect to be realized byusing the inverter technology is 12%, payback can be only achieved with electric refrigerators
consuming approximately 650 kWh/year or more.
This means that payback would not be possible with top models among electric
refrigerators having rated internal volume of 300L or lower (approximately 550 kWh/year).

10Basic idea about establishment of judgment standards of manufacturers, etc. (Excerpt)
Principle 5: In the case in which any existing products may become expensive due to a high-level
energy saving technology and in which the possibility is extremely high that a price increaseaccompanying introduction of said energy saving technology cannot be recovered by loweringrunning cost in a certain period taking utilization of the product into account, a distinct class
may be set for the products, as necessary.
(4) Classification by the Number of Doors in a Chiller Section
To secure space for opening a door, production of electric refrigerators having chiller door
configuration of “2-door for a chiller section (Figure 2, so-called side-by-side door or Frenchdoor)” has increased, in addition to ones of “1-door for a chiller section (Figure 1)”. For large
electric refrigerators, in particular, this tendency is more common because area of a chiller door
is larger. In electric refrigerators having rated internal volume of 401L or greater, over half ofapproximately 1.564 million units of shipped refrigerators, i.e., approximately 870 thousands
units have 2 chiller doors (surveyed by the Japan Electrical Manufacturers’ Association, 2005).
However, those with 2 chiller doors consume more power approximately 30 kWh/year
than those with 1 chiller door. It is because the former have a dew formation prevention heatermounted in the center of the doors (See page 24).
Thus, in order not to hinder consumers’ needs, classification by door configuration of achiller section shall be established.

Figure 1 Single Door (for a chiller section)

Figure 2 Double Door (for a chiller section)11

3. Setting of Basic Classification Proposal
As shown in the list below, a proposal for basic classifications shall be set:
Table 3:Category

StorageA
B
C

Refrigerators(including
refrigerator-freezers)

Proposed Classification of Electric Refrigerators
Cooling Type

Rated
Internal
VolumeNumber ofDoors in
Chiller Section

Cold air-naturalconvection type－－

300L orlower－

Cold air-forced
circulation type1 doorOver 300 L

D
Cold air-naturalconvection typeE
Freezers

F
G

Cold air-forced
circulation type2 doors or
more

－

－

300L or
lower－

Over 300 L－

Production
Volume*(Composition
Ratio)
291,318 units(6.8％)
1,332,260 units(31.3％)
1,613,081 units(37.9％)
864,486 units(20.3％)
31,687 units(0.7％)
120,988 units(2.8％)
0 unit*Production volume in fiscal 2005 (surveyed by The Japan Electrical Manufacturers’ Association)

12

(Reference)
Effects of Internal Temperature Compensating Heater
For electric refrigerators of forced circulation type and having rated internal volume of
300 L or greater, in order to respond to consumers’ needs, those models called as, for instance, abottom freezer type, center-mounted crisper type, vertical vegetable compartment type, etc. aresupplied on the market. Although it is difficult to define them categorically, we divide them into
one type whose crisper abuts on a freezer on one side and another type whose crisper abuts on afreezer on two sides. In 2005, the former accounts for 65% of the total shipments, while thelatter accounts for 35%.
As shown in Figure 1 and Figure 2, the models whose crisper abuts on a freezer on twosides are characterized in that temperature is being regulated by means of a heater such as heating
wire, etc., because they are more susceptible to a freezer than those having a crisper abutting on afreezer on one side, and thus tend to be cooled over necessary. In term of annual energy
consumption, the former consumes about 70 kWh/year over the latter, as shown in Figure 3.
We decided not to establish a category by internal temperature compensating heater,
however, for the following reasons. It is difficult to define them categorically, because a numberof configurations are assumed depending on how they abut, i.e., whether only a part of a side of acrisper abuts or a whole side abuts. In addition, installation of an internal temperaturecompensating heater varies in individual models, depending on layout of a crisper, freezer, icecompartment, switching compartment. In addition, we believe that classifying all these models
in one same category would promote improvement in installation of an internal temperaturecompensating heater, thereby encouraging further reduction of energy consumption.

Chiller

Ice
Compartment

Chiller

SwitchingCompartment

Ice
Compartment

SwitchingCompartment

Freezing
Compartment

Crisper

CrisperFreezing
Compartment

Figure 1

Figure 213扉１枚・野菜室１面
扉２枚・野菜室１面
扉１枚・野菜室２面
2-door/two sides of a crisper abutting
扉２枚・野菜室２面
Reference line of 1-door/one side of a crisper
abutting
扉１枚・野菜室１面基準線
Reference line of 2-door/one side of a crisper
abutting
扉２枚・野菜室１面基準線
Reference line of 1-door/two sides of a crisper
扉１枚・野菜室２面基準線
abutting
Reference line of 2-door/two sides of a crisper
扉２枚・野菜室２面基準線
abutting
1-door/one side of a crisper abutting

900

2-door/one side of a crisper abutting

1-door/two sides of a crisper abutting

850
800
750

kWh/year
kWh／年

700
650
600
550
500
450
400
350

400

450

500

550

600

650

700

750

Adjusted
Internal Volume (L)調整内容積（Ｌ）

Figure 3: Differences in Annual Energy Consumption Depending on
Number of Sides that Heater Abut on

14

800

Attachment 4
Target Standard Values of Electric Refrigerators
1. Idea on Setting Target Standard Values(1) Basic Idea
We shall set target standard values based on the idea of Top Runner Program. The specificpolicy shall be as follows:
1) A target standard value shall be set for every appropriately defined category.
2) For any category for which possible improvement of efficiency is anticipated because of
future technology advancement, a target standard value shall allow for the improvement
wherever possible.
3) Target standard values shall not be inconsistent among categories.
(2) Possible Improvement of Energy consumption efficiency Attributed to Future Technology
Advancement
Possible improvement in energy consumption efficiency is assumed, as shown below:
Table 1: Possible Improvement in Energy Consumption Efficiency
Category

Elements of Improved Efficiency

Possible Improvement

A, E

・ Improved efficiency of a compressor, improvement of heatinsulation characteristics/wall thickness, nonuse of CFC
(10%)

10%

B, F

・ Improved efficiency of a compressor (3%)

3%

C, G

D

・ Improved efficiency of a compressor (4%)
・ A difference of approximately 70 kWh/year depending on
installation status of aninternal temperaturecompensating heater・ Improved efficiency of a compressor, optimization ofcalorific power of a heater of dew condensation prevention
type (6%)
・ A difference of approximately 70 kWh/year depending on
installation status of aninternal temperaturecompensating heater

15

1%

3%

2. Specific Calculation Formula of a Target Standard ValueAs energy consumption efficiency correlates to adjusted internal volume (*), a calculation
formula of a target standard value of electric refrigerators, etc. shall be expressed by a linear
function expression with energy consumption efficiency and adjusted internal volume as variables.
In principle, the specific calculation formula shall be developed for each category according to thefollowing procedure:
The target products shall be categorized by every 50 L of adjusted internal volume, and thehighest energy consumption efficiencies in each category shall be defined as top values. Then, agroup of the top values shall be subject to simple regression, in order to determine a slope. After
that, an intercept shall be determined so that none of the top values lies below the line with thedetermined slope. Thus, a calculation formula of a target standard value shall be set.
In addition, since energy consumption efficiency of electric refrigerators and electricfreezers can be corrected by adjusted internal volume, these of the same type shall have the sametarget standard value.
* Electric refrigerators are composed of a chiller and a freezer, etc., and every product ofrefrigerators and freezers has a different capacity ratio between a chiller and a freezer. In
order to compare them under the same conditions, we decided to use adjusted internal volume
that is corrected with external temperature and internal temperature of the products.
Table 2: Target Standard Value Calculation Formula of Electric Refrigerators (including Electric
Refrigerator-Freezers)
Number ofRated Internal
Target Standard Value
Category
Cooling TypeDoors in Chiller
VolumeCalculation Formula
SectionCold air-natural convection－A
E=0.844Vadj+155－
type
B
300L or less
E=0.774Vadj+220－
Cold air-forced circulation
COne
E=0.302Vadj+343
typeOver 300L
D
2 or more
E=0.296Vadj+374

CategoryE
F
G

Table 3: Target Standard Value Calculation Formula of Electric Freezers
Rated Internal
Target Standard Value
Cooling Type
Door of Chiller
VolumeCalculation Formula
Cold air-natural convection－
E=0.844Vadj+155－
type
300L or less
E=0.774Vadj+220
Cold air-forced circulation－
type
Over 300L
E=0.302Vadj+343

Notes 1: E: Energy consumption efficiency (kWh/year)
2: Vadj: Adjusted internal volume (unit: L)
1) For a refrigerator-freezer and a freezer whose freezing compartment is of three-star type,
Vadj shall be a numeric value obtained with the following formula:
Vadj= 2.20 x V (Rated internal volume of a freezing compartment) + V (Rated internal
volume of other than a freezing compartment)
The coefficient of 2.20 is determined by the following calculation, consideringrespective differences among the external temperature of 22.4°C, the internal
temperature of a freezer of -18°C, and that of a refrigerator of 4°C.
2.20 = (22.4°C-(-18 °C))/(22.4 °C -4 °C) = 40.4/18.4
2) For a refrigerator-freezer and a freezer whose freezing compartment is of two-star type,
Vadj shall be a numeric value obtained with the following formula:
Vadj= 1.87 x V (Rated internal volume of a freezing compartment) + V (Rated internal
volume of other than a freezing compartment)
The coefficient of 1.87 is determined by the following calculation, considering16

respective differences among the external temperature of 22.4°C, the internal
temperature of a freezer of -12°C, and that of a refrigerator of 4°C.
1.87 = (22.4 °C -(-12 °C))/(22.4 °C -4 °C) = 34.4/18.4
3) For a refrigerator-freezer and a freezer whose freezing compartment is of one-star type,
Vadj shall be a numeric value obtained with the following formula:
Vadj= 1.54 x V (Rated internal volume of a freezing compartment) + V (Rated internal
volume of other than a freezing compartment)
The coefficient of 1.54 is determined by the following calculation, consideringrespective differences among the external temperature of 22.4°C, the internal
temperature of a freezer of -6°C, and that of a refrigerator of 4°C.
1.54 = (22.4 °C -(-6 °C))/(22.4°C -4 °C) = 28.4/18.4(For Your Reference)
Three-star type :Two-star type :One-star type :A freezing compartment whose average freezing load
temperature of which is –18 °C or lower
A freezing compartment whose average freezing load
temperature of which is –12 °C or lower
A freezing compartment whose average freezing load
temperature of which is –6 °C or lower

17

Energy
Consumption Efficiency (kWh/year)
エネルギー消費効率（kWh/年）(Reference 1)

1100

900

700

y = 0.844x + 155

500
y = 0.938x + 172
300
y = 0.938x + 207
100
0

200

400

600

800

1000

Adjusted
Internal Volume (L)調整内容積（Ｌ）

Figure 1: Target Standard Value Calculation Formula (Category A and E)

EnergyConsumption Efficiency (kWh/year)
エネルギー消費効率（kWh/年）

650

550

450
y = 0.774x + 220

350

y = 0.798x + 227
y = 0.798x + 249

250
150

200

250

300

350

Adjusted Internal Volume (L)調整内容積（Ｌ）

Figure 2: Target Standard Value Calculation Formula (Category B and F)

18

400

Energy
Consumption Efficiency (kWh/year)
エネルギー消費効率（kWh/年）

750

650

550

y = 0.302x + 343

450
y = 0.305x + 346
350
350

450

550
650
Adjusted Internal Volume (L)調整内容積（Ｌ）

750

Figure 3: Target Standard Value Calculation Formula (Category C and G)

EnergyConsumption Efficiency (kWh/year)
エネルギー消費効率（kWh/年）

900

800

700

600

500
y = 0.296x + 374
y = 0.305x + 386

400

300
350

450

550
650
調整内容積（Ｌ）
Adjusted
Internal Volume (L)750

Figure 4: Target Standard Value Calculation Formula (Category D)

19

Energy
Consumption Efficiency (kWh/year)
エネルギー消費効率（kWh/年）

900

800

700

600

500

y = 0.305x + 413

400
350

450

550

650

750

Adjusted
Internal Volume (L)調整内容積（Ｌ）

Figure 5: Calculation of Slope for Category C, D and G

区分Ａ、Ｅ
区分Ｂ、Ｆ
区分Ｃ、Ｇ
Categories
C, G
区分Ｄ
CategoryD
Linear(TargetStandard Value Calculation Formula (A, E))
線形(目標基準値算定式（Ａ、Ｅ）)
線形(目標基準値算定式（Ｂ、Ｆ）)
Linear(TargetStandard Value Calculation Formula (B, F))
線形(目標基準値算定式（Ｃ、Ｇ）)
Linear(TargetStandard Value Calculation Formula (C, G))
線形(目標基準値算定式（Ｄ）)(TargetStandard Value Calculation Formula (D))
LinearCategories A, E

900エネルギー消費効率（kWh/年）

Energy Consumption Efficiency (kWh/year)

Categories B, F

Category A, E
区分Ａ、Ｅ

Category D
区分Ｄ

700
Category B, F
区分Ｂ、Ｆ

500

Category C, G
区分Ｃ、Ｇ

300

100
0

200

400

600

Adjusted Internal Volume (L)調整内容積（Ｌ）

Figure 6: Target Standard Value Calculation Formula (Overall)

20

800

(Reference 2)
Examples of Major Techniques for Improving Efficiency of Electric Refrigerators(1) Compressor[Reduction of Mechanical Loss]
For mechanical loss, it is effective to take a measure to reduce loss mainly in a sliding unit ofa bearing/crankshaft as well as in a sliding unit between a piston/cylinder of a compressing unit,
whereby an attempt to maximally reduce a sliding area is made and a motor input value is reduced,
while reliability is secured. For a piston, in particular, a new surface treatment is adopted inattempt to reduce sliding loss.

CylinderPistonBearing
Crankshaft
Rotor[Reduction of Intake/Discharge Loss]
Compression efficiency is improved by tuning valves or an intake muffler so that arefrigerant is sucked and discharged smoothly.
[Rotation at Slower Speed]
To implement slower rotation and thereby reduce input substantially, a fueling mechanism of
a crankshaft is improved, and thus rotation is slowed down.
(2) Motor for Compressor[Shape of Rotor Magnet]
Through the use of an improved IPM motor that has better motor efficiency than aconventionally used SPM motor, a change to a lighter motor with higher efficiency isimplemented.

MagnetMagnet

SPM Motor

IPM Motor[Improvement of Winding]
One of measures to improve the motor efficiency is to increase the ratio of winding to widen
coil section area by rolling more motor windings in a limited motor space. It reduces resistanceof motor winding and thus copper loss is also reduced.Increased ratio of winding is implemented
through design improvement of adopting salient-pole concentrated winding method in which
winding is directly rolled around a stator.
In addition, in order to improve motor efficiency during slow rotating operation, which has
an effect on energy saving of refrigerators, tuning of length of winding and cross section has been21

attempted[Magnetic Steel Sheet with Low Iron Loss]
As motor iron loss, there are hysteresis loss and eddy current loss. Currently, to reduce theeddy current loss, silicon steel sheet with low iron loss is now adopted and thinning thereof is
attempted.
(3) Insulation Technology
Gas thermal conductivity of a foaming agent is the biggest factor to determine insulation
efficiency of polyurethane heat insulator. It has been changed as shown in the following list,
because global environment-protection measures (reduction of ozone depletion substances andglobal warming substances) need to be prioritized.
Period of Use

1970

1990 – 2003

1994 –Name of Foaming Agent

CFC-11

HCFC-141b

Cyclopentane

Boiling Point (°C)

24

32

49

(W/mK)

0.011

0.013

0.018

ODP (Ozone Depletion

1.0

0.11

0

1.0

0.25

＜0.01

Gas Thermal Conductivity

Potential)
GWP (Global Warming
Potential)
The gas thermal conductivity of foaming agent used as shown in the above table has
worsened. In addition, elevation of boiling point of foaming agent gas has prompted deteriorationof thermal conductivity by liquefaction during cooling.
Improvement of gas thermal conductivity of cyclopentane has now reached a limit. Consequently,
improvement of power consumption has been attempted through enhancement and extended use of
vacuum insulation material.
By adopting a heat insulation system combined conventional urethane with vacuum
insulation material, which has 10 times higher insulative property than the former, for heatinsulation between outer wall and inner box of a refrigerator, about 25% reduction of heat loss has
been achieved.

22

Conventional
Heat-Insulated Structure

Heat-insulated Structure
adopting <non-CFC vacuum
insulation material>
Non-CFC Vacuum
Heat Insulator

Non-CFC Foam
Insulator

Non-CFC Foam
Insulator
Inside Wall

Inside Wall

Outer
Wall

Outer Wall

Image View of Non-CFC
insulation material (Gray Area)

VacuumFor a vacuum insulation material, improvement of insulative property is under way throughenhancement of degree of vacuum and reduction of influence of heat bridge (heat wraparound) bychanging aluminum evaporation coating of outer shell from all-surface to single-surface.
(4) Adoption of Natural Refrigerant
In order to reduce GWP, a rapid shift of a refrigerant from HFC-134a to R600a, naturalrefrigerant (isobutane), is taking place. Although R600a is a flammable refrigerant and thus
needs careful handling, it is expected to improve cycle efficiency by about 7%.
Characteristics of Refrigerants
Refrigerant
HFC-134a
R600a
ODP (Ozone Depletion
00Potential)
GWP (Global Warming
1300
3
Potential)(As C02=1)(As C02=1)
Freezing capacity
100 (Reference)
Approx. 57 (low)Theoretical COP (%)
100 (Reference)
Approx. 107 (Good)Classification of burning
Noncombustible gas
Combustible gas (lower limit 1.8 vol%,qualityupper limit 8.4 vol%)(5) Optimization of Cold Air TrunkConventionally, for optimization (simulation) designing by thermo-fluid analysis, only apartial analysis was made. However, higher performance of PC and software has now enabledlarge-scale calculation, thereby optimum designing for the whole has been implemented.

23

(6)

Internal Temperature Compensating Heater
For a temperature compensating heater in a crisper, an attempt to reduce heater capacity ismade by optimal control of heater energization ratio depending on outside temperature andinternal temperature, etc., and by improved insulative property of compartment wall by means ofreexamining its thickness between a crisper and a freezer and adopting high efficient urethane as aheat insulator, etc.

Chiller

Ice
Compartment

Chiller
4℃

Ice Compartment/SwitchingCompartment -18℃

SwitchingCompartment

Spaceof -18℃

CoolerCrisper: 5℃

CrisperFreezing
Compartment: -18℃

Freezing
Compartment

HeaterSectional Side Elevation

Front View

(7) Dew Formation Prevention Heater
As illustrated below, in an electric refrigerator of “side-by-side door” type, “a partition forpreventing leak of cold air” is placed between the two doors for the purpose of curbing spill of thecold air. However, outside surface of a refrigerator may be cooled due to temperature within
the refrigerator (thermal conduction), and, in some cases, dew may be formed on the partition
surface, depending on environmental conditions such as temperature/humidity, etc of a place
where a refrigerator is installed. Hence, as a measure to prevent such dew formation, a heater isarranged inside the partition (See the figure below), thereby controlling thermal conduction of theheater according to the environment where a refrigerator is installed and its operating conditions.
Consequently, refrigerators of double door type may contribute to a higher electric bill thanthose of single door type, depending on status of use. In a case that a partition is secured to thebody of a refrigerator, when it is opened, the partition limits the usable space, and its usability will
be worsened. Thus, the structure where the partition is attached to a door and moves along withthe door when it is opened has now become prevalent (See the figure below).
By incorporating a part of a heat radiator of a freezing cycle inside a partition and thus
generating heat, such a partition secured to a refrigerator body could prevent dew formation
without using an electric heater. In case of a movable partition, however, it is difficult toincorporate a heat radiator inside. Thus, in the present circumstances, there is no technique toprevent dew formation that can substitute for installation of an electric heater.
However, it is necessary to address reduction of power consumption through optimization ofelectric conduction ratio of a heater or improvement of insulative property of a partition.

24

Refrigerator
Body
Shelf

BottlePocketDoor

Partition for Preventing Leakof Cold Air“Single Swing” Type“Side-by-Side” TypePartition for Preventing Leak ofCold Air
Dew Formation Prevention Heater
Partition for Preventing Leak ofCold AirWhen doors of a side-by-side type are opened

Enlarged View of Periphery of the Partition25

Attachment 5

Energy Consumption Efficiency of Electric Refrigerators and Measurement Method
1. Basic Idea
In the case of electric refrigerators, when they were designated as top runner target products
in 2000, as a realistic index of energy consumption efficiency, “annual energy consumption”
measured by the method specified in JISC9801:1999 was adopted.
However, the measurement method specified in JISC9801: 1999 reflects a situation far from
actual status of use because of difference in setting of internal temperature controller and in heater
operation due to effects from installation requirements and ambient temperatures, etc. Therefore,
JISC9801:1999 was reviewed, and JISC9801:2006 was promulgated on May 1, 2006. Since
JISC9801:2006 is a measurement method close to actual status of use, it is considered reasonable
to adopt JIS9801:2006.
2. Specific Energy Consumption Efficiency and Measurement Method
The energy consumption efficiency for electric refrigerators shall be annual energy
consumption (for ones supporting both rated frequency of 50 Hz and 60Hz, a numeric value
measured with respective frequencies, whichever is larger), and a measurement method shall be
the method specified in JISC9801: 2006. For a refrigerator-freezer that is a freezer capable ofswitching to cooling mode equivalent of a chiller, it shall be a numeric value measured in
respective modes, whichever is larger.

26

(Reference)
Major Revisions to JISC9801
1. Ambient Temperature of a Refrigerator when Measuring Power Consumption
The survey about kitchens of general household in 8 prefectures across the country (i.e., a
total of 23 kitchens in condominium buildings and stand-alone buildings in Hokkaido, Miyagi,
Tokyo, Osaka, Okinawa, etc.) was conducted. Based on the survey results, such as annual
average room temperature, the conventional one-point measurement (25°C±1°C) was changed to
two-point measurement (30°C±1°C (summer) and 15°C±1°C (winter)). If measurement takes
place at 2 points, namely 15°C and 30°C, the function that does not work at the conventional
one-point temperature setting (25°C) (e.g. a temperature compensating heater to be used forprevention of freezing in a crisper) does operate, and thus power consumption will be closer toactual status of use.
2. Other Conditions during Measurement of Energy Consumption
To measure power consumption in the condition closer to actual state of use, plastic bottles
containing water shall be placed according to respective volumes of a chiller and a freezing
compartment, and such optional functions as automatic ice making or deodorizing shall be run.
3. Installation Condition (Distance to Wall) of a Refrigerator when Measuring Power Consumption
The refrigerator installation environment in approximately 1,300 general households acrossthe country was surveyed. Based on the result, a distance between wall and a refrigerator during
the measurement was changed from 30 cm, the numeric value in the conventional standard, to 5
cm that is closer to the actual status. This could make power consumption be closer to the actual
status in which effect of heat to be reflected back from the wall is considered.
4. Internal Temperature Setting of a Chiller during Measurement of Power Consumption
The internal temperature setting was changed from the conventional 5°C to 4°C, according
to actual status.
5. Number of Opening/Closing of Chiller Door during Measurement of Power Consumption
Based on results of monitoring surveys, number of opening/closing of chiller door waschanged to conventional 25 times to 35 times.
<<Browsing of JISC9801:2006>>
For JISC9801:2006, refer to Home Page of Japanese Industrial Standards Committee(http://www.jisc.go.jp/).

27

Attachment 6

Electric Refrigerator Evaluation Standards Subcommittee
Energy Efficiency Standards Subcommittee of the Advisory Committee for Natural Resources andEnergyBackground of Holding

First Subcommittee Meeting (September 28, 2005)
・Disclosure of Electric Refrigerator Evaluation Standards Subcommittee
・Achievements of electric refrigerators
・Current situation of commercial electric refrigerators
・Current situation of home electric refrigerators
・Scope of electric refrigerators to be covered
・Energy consumption efficiency and measurement method
Second Subcommittee Meeting (January 24, 2006)
・Energy consumption efficiency and measurement method of electric refrigerators
・Idea on revision of classification of electric refrigerators
Third Subcommittee Meeting (May 9, 2006)
・Consecutive changes in annual energy consumption in actual use
・Classification of electric refrigerators for setting targets
・Target standard value and target fiscal year of electric refrigerators
・Others
Fourth Subcommittee (May 25, 2006)
・Interim summary report

Interim summary report was open for public comments during the period from May 27, 2006 throughJune 27, 2006; however, no particular comment was received. Thus, it became the final summary
report.

28

Attachment 7

Electric Refrigerator Evaluation Standards Subcommittee, Energy Efficiency Standards
Subcommittee of the Advisory Committee for Natural Resources and Energy
List of Members
ChairmanMembers

Koichi WATANABE, Emeritus Professor, Keio University
Kenji AMANO, Project General Manager, Medical Equipment/Reliability Test
Department, Safe Electromagnetic Center, Japan Quality Assurance Organization
Hiroyuki UEMURA, Vice-Chairman, Electric Refrigerator Environment-responsive
Committee, Japan Electrical Manufacturers’ Association (since the 3rd meeting)
Katsuhiko KADOGUCHI, Head of Heat Utilization Group, Technology Research
Dept., National Institute of Advanced Industrial Science and Technology
Akihito KANAI, Assistant Vice-President of Planning Department and AssistantGeneral Manager of Development Division, Japan Consumers’ Association
Hiroyuki KUDOU, General Manager of Technology, Energy Conservation Center,Japan
Yoshiro SHIBATA, Chief Scientist, Jukankyo Research Institute, Inc.
Kikuko TATSUMI, Director/Environment Committee
ASSOCIATIOIN OF CONSUMER SPECIALISTS

memberof

NIPPON

Kiyohide HATA Chairman, Electric Refrigerator Technology Ad-hoc Committee,
Japan Electrical Manufacturers’ Association (since the 3rd meeting)Eiji TOBIHARA, Professor specialized in environmental studies, Graduate School of
Frontier Science, University of Tokyo
Yoichi HORI, Professor, Institute of Industrial Science, University of Tokyo

29

Reference 1
Consecutive Changes in Annual Energy Consumption in Actual Use
1. Background
With this revision of JISC9801, annual energy consumption measured by the conventional
measurement method widely changed.
Hence, in order to verify whether actual efficiency was improved by introducing the top
runner program, it was decided to check a transition in annual energy consumption since
introduction of the top runner program, with a new measurement method.
Note that previously shipped items were checked by estimates (specific models(center-mounted-crisper type of 450L class)) because their production had been stopped.
2. Transition of Annual Energy Consumption in Actual Use
The estimates of annual energy consumption of each year according to the newmeasurement method were studied (Fiscal 1998=100). It certainly decreased every year, whichmeans that introduction of the Top Runner Program steadily improved efficiency.
For the annual energy consumption per unit adjusted internal volume, improvement ofefficiency has also steadily progressed.
(For your reference: method of estimating annual energy consumption)
Since power consumption has been routinely measured at 30℃ and 15℃ as a part ofperformance test, estimation was made based on the data.
However, measurement conditions of the performance test do not include opening/closing ofdoors, etc, the past annual energy consumption was estimated by using a coefficient which is adifference between annual energy consumption by the new JIS9801 in 2005 and that by theperformance test in 2005.
In addition, for the purpose of maintaining consistency, data of a manufacturer that has been
manufacturing electric refrigerators of a specific model (450L class/ center-mounted-crisper type)since 1998 was used.
Fiscal Year
Annual energy consumption in
actual use (Estimates)(Index: Fiscal 1998=0)
Annual energy consumption perunit adjusted internal volume(kWh/year L)

98
100

99
95

00
91

01
89

02
86

03
82

04
79

05
67

1.9

1.8

1.7

1.7

1.6

1.5

1.4

1.2

30

(Reference)
120

Index:指数：1998年度=100
Fiscal 1998=100

110
100
90
80
70
60
50
40
1998

98年

1999

99年

2000

00年

2001

01年

2002

02年

2003

03年

2004

04年

2005

05年

Estimatesof Actual Use per Unit Adjusted Volume (kWh/year L)
単位調整容積当たり実使用推定値[kWh/年・Ｌ]

Figure 1: Transition in Annual Energy Consumption in Actual Use (Estimates)

2.0
1.9
1.8
1.7
1.6
1.5
1.4
1.3
1.2
1998
98年

1999
99年

2000
00年

2001
01年

2002
02年

2003
03年

2004
04年

2005
05年

Figure 2: Transition in Annual Energy Consumption per Unit Adjusted Internal Volume (Estimates)

31

Reference 2
Method of Measuring Energy Consumption of Commercial Electric Refrigerators
1. Proceedings
The Japan Refrigeration and Air Conditioning Industry Association (JRAIA) conducted asurvey on a measurement method of energy consumption of products and use environment in amember company. Based on the survey result, JRAIA developed an energy consumption trial
computation model of commercial electric refrigerators and carried out proving tests. Then,
JRAIA summarized measurement results and standardized a method of measuring energy
consumption of commercial electric refrigerators (industry standard JRA4032).
2. Issues
Although a measurement method exists as an industry standard, measurement data often has
substantial variations. Thus, it is necessary to verify its repeatability. In addition, since it has
been confirmed that a measurement method specified in the measurement method of household
electric refrigerators (JISC9801) which was used as reference employs a condition far from actual
status of use, any method capable of measuring energy consumption closer to actual usage shallalso be considered.
To be specific, JRAIA shall review on scope setting of devices that measure energy
consumption with the same measurement method, verification of repeatability of measured data,and evaluation of energy consumed by optional equipment that was excluded from themeasurement.
3. Future Schedule
For a measurement method of energy consumption of commercial electric refrigerators,
JRAIA shall survey market status, verify measurement data, etc., and then review the industry
standard within 2006.
Based on this, JIS standardization of the measurement method and addition of the product to
the Top Runner’s targets shall be examined.

32Reference 3

Current Status of Household Electric Refrigerators andHousehold Electric Freezers

33

1. Market Trend of Household Electric Refrigerators and Freezers
1-1 Domestic Demand (Production Volume, Amount, Import/Export Volume)
In Japan, small refrigerators (90 litters) for home use were first released in 1952. Since then,refrigerators have become dramatically widespread as household requisites while internal volume has been
increasing and functionality has been improving along with enrichment of dietary life. Until 1975, every
home had at least one refrigerator, and thus currently replacement is a main demand.
On the one hand, production at overseas factory has increased recently, while domestic production is
on downward trend.
Table 1: Domestic Demand of Electric Refrigerators(Calendar Year, Unit: 1000 units, 1.0 million yen)

Volume ofdomestic
production(A)
Amount ofdomestic
production
ImportVolume (B)

1975

1980

1985

1990

1995

2000

2001

2002

2003

2004

3,474

4,282

5,354

5,048

5,013

4,224

3,875

3,317

2,859

3,020

212,641

349,196

435,140

457,673

492,904

435,071412,276

324,926

280,743

315,649

76

60

10

356

717

1,463

1,769

1,923

1,827

2,008

Export
332
696
1,905
444
262
208
75
64
68
69
Volume (C)Domestic
Demand
3,218
3,646
3,459
4,960
5,468
5,479
5,569
5,176
4,618
4,959
(A+B-C)
Source: Domestic production & amount: current survey of industrial production by Ministry of Economy,
Trade and Industry
Import/export volume: customs statistics by Ministry of Finance
Table 2: Domestic Demand of Electric Freezers(Calendar Year, Unit: 1000 units, 1.0 million yen)

Volume ofdomestic
production(A)
Amount ofdomestic
production
ImportVolume (B)

1975

1980

1985

1990

1995

2000

2001

2002

2003

2004

111

109

102

111

207

134

123

82

71

47

4,707

6,802

7,576

9,745

19,54016,382

17,052

13,863

13,16312,803

-

4

1

26

172

230

261

276

273

373

Export
40
13
3
3
6
5
7
7
8
Volume (C)Domestic
Demand
73
90
134
376
358
379
351
337
412
(A+B-C)
Source: Domestic production & amount: current survey of industrial production by Ministry of Economy,
Trade and Industry
Import/export volume: customs statistics by Ministry of Finance34

Figure 1: Domestic
Demands of Electric Refrigerators and Electric Freezers
図１ 電気冷蔵庫及び電気冷凍庫の国内需要
6,000

5,000

4,000

1,000
千台 3,000
units
2,000

1,000

0

1975

1980

1985

1990

1995

2000

2001

2002

2003

2004

Year
年
Domestic demand of electric
refrigerators

電気冷蔵庫の国内需要

Domestic demand of electric
電気冷凍庫の国内需要
freezers

Demand for electric freezers is even below 10% of that of electric refrigerators, and accounts forapproximately 8.3% of demand of electric refrigerators in 2004. It is considered that the increased demandin 1990 is a result from increased demand for larger refrigerators due to Heisei (bubble) boom since 1987.
The table below shows the transition of domestic production and import/export volumes of electric
refrigerators

Figure 2: Transitionof Domestic
Production and Import/Export Volumes of Electric
図２
電気冷蔵庫の国内生産及び輸出入の推移
Refrigerators
6,000

5,000

4,000

1,000
units 3,000
千台
2,000

1,000

0

1975

1980

1985

1990

1995

2000

2001

2002

Year
年

国内生産台数(A)Domestic Production Volume (A)

輸入台数(B)

Import Volume (B)35

輸出台数(C)

Export Volume (C)

2003

2004

Although domestic production and export increased till 1985, export has decreased since then, due tostrong-yen recession. In 2004, volume ended in just under 70,000 units.

Figure3: 図３
Transition
in Domestic Production of and Import/Export of Electric
電気冷凍庫の国内生産及び輸出入の推移
Refrigerators
400
350
300
250

1,000
200
千台
units
150
100
50
0

1975

1980

1985

1990

1995

2000

2001

2002

2003

2004

Year
年

国内生産台数(A)Domestic Production Volume (A)

輸入台数(B)

Import Volume (B)

輸出台数(C)

Export Volume (C)For electric freezers as well, import has been increasing since 1995, while domestic production has
declined. In 2004, proportion of domestic production to import is 12%.
1-2 Transition in Volume of Shipment of Electric Refrigerators by Internal Volume
According to the survey of Japan Electrical Manufacturers’ Association, transition by capacity is asshown in the figure, and a “shift to large volume” of refrigerators has become noticeable since 1990. The data
in 2004 has shown that large refrigerators having internal volume of 300L or more have a majority of the total
shipment. In recent years, super-large refrigerators of 401L or more accounts for 36%.
On the one hand, small refrigerators of 140L or less have still deep-rooted popularity of 30% level among
students and unmarried households.

36

Figure 4: Transition in Domestic Shipment by Capacity of Electric Refrigerators

図4 電気冷蔵庫の容量別国内出荷の推移

5000

Unit: 1,000 units

4500
4000
3500
3000

単位:千台 2500
2000
1500
1000
500
0

1975

1980

1985

1990

1995

2000

2001

2002

2003

2004

Year
年

小型

Small

中型

Medium

大型

Large

超大型

Super-large

Table 3: Transition in Shipment by Capacity and Composition Ratio of Electric Refrigerators(Unit: 1,000 units)
1975
1980
1985
1990
1995
2000
2001
2002
2003
2004
635
847
1,037
1,596
1,449
1,432
1,433
1,372
1,311
1,338
Small
(19%)
(23%)
(28%)
(34%)
(31%)
(29%)
(29%)
(31%)
(31%)
(30%)
2,697
2,661
1,634
1,018
679
553
570
543
521
565
Medium
(81%)
(71%)
(44%)
(22%)
(14%)
(11%)
(12%)
(12%)
(12%)
(13%)
0
234
1,029
2,018
1,468
1,369
1,530
1,044
903
955
Large
(6%)
(28%)
(44%)
(31%)
(28%)
(31%)
(24%)
(21%)
(22%)
Super1,098
1,531
1,356
1,440
1,497
1,575
large
(23%)
(31%)
(28%)
(33%)
(35%)
(36%)
Total
3,332
3,742
3,700
4,631
4,693
4,885
4,888
4,399
4,233
4,433
(Notes) 1. Refrigerators of 140L or less are classified as small, those of 141 to 300L as medium, those of 301 to
400L as large (super-large refrigerators before 1990 were addressed as large), and those of 401L or
more as super-large.
2. The percentage in parentheses represents the composition ratio of each year.
3. Since this statistics show volume of shipment among member companies of the Japan Electrical
Manufacturers’ Association, they differ from the numeric values shown in Table 1.
Source: Independent statistics by the Japan Electrical Manufacturers’ Association
1-3 Domestic Major Manufacturers
They include SANYO Electric Co., Ltd., Sharp Corporation, Toshiba Consumer Marketing Corporation,
Hitachi Appliances, Inc., Matsushita Electric Industrial Co., Ltd., Mitsubishi Electric Corporation, and soon.
1-4 Import Manufacturers
They include M&M (China), LG Electronics (South Korea), Electrolux (Sweden), Samsung Electronics(South Korea), GE (United States), Daewoo (South Korea), Haier (China), Whirlpool (United States), andso on.

37

2. Energy Saving Measures for Household Refrigerators
2-1 Transition of Energy Saving Technologies for Refrigerators
Development of energy saving technologies undertaken by every manufacturer has substantially reduced
power consumption of refrigerators. Temporary rise in power consumption in 1993 and 1994 was attributed toeffects of changes in refrigerant and heat insulator foaming agent responding to abolition of specified CFC.

Figure 5:
Energy Consumption per 1L (kwh/L)
図５Annual
１L当たり年間消費電力量（kwh/L）

3.00

kWh/year/L
kWh/年/L

2.50
2.00
1.50
1.00
0.50
0.00
91

92

93

94

95

96

97

98

99

00

01

02

03

Year
年
Annual Energy Consumption per 1L (kWh/L)
１Ｌ当り年間消費電力量（ｋＷｈ/Ｌ）

Source: Japan Electrical Manufacturers’ Association
Note: Although the method of measuring energy consumption was changed in 1993 and 1999 (because JIS
was revised), correction was made with a coefficient which is a difference in data caused by difference
in measurement method.

38

2-2 Improvement of Energy-Saving Technologies
In Japan, energy-saving technologies for refrigerators have reduced energy consumption throughaccumulation of three basic technologies. The table below summarizes a relationship among major basic
energy-saving technologies.
Table 4: Major Basic Energy-Saving Technologies
Basic Technology
Technology Item
Element
Cooling
Efficiency of compressors
Technology
Improved condensation
efficiency
Optimization of cold air
trunk
Insulation
high-efficiency ofTechnology
insulation material
Improvement ofheat-insulated structure
Control
Optimization of heater
Technology
control
Optimization of cooling
circuit
Reduced torque at startup

Specific Cases
Motor efficiency, compression efficiency, adoption of
isobutane as a refrigerant, etc.
Mounting location of a condenser, shape/heat release area, etc.
Review and improvement of cold air flow
Expansion of area in which a vacuum insulation material isused, etc
Insulation effect of door gaskets (shape)
Heat quantity control of various types of temperaturecompensating heaters
Improved heat loss due to a stopped compressor
Low consumption during stable operation

Inverter technology

Improved efficiency of cooling cycle

In addition, these technologies have facilitated reduction of power consumption of household
refrigerators.
Typical technologies for reduction of power consumption of refrigerators include the following:(1) Improved efficiency of a compressor (Improvement of motor efficiency)
A change to a highly-functional motor that drives a compressor has increased motor efficiency and slowed
down rotation of a compressor, thereby saving energy.
Figure 6: Circuit Example
Alternating
Current

DirectCurrent

Fixed Voltage

Alternating
Current

InverterInverter Circuit

Converter Circuit
Fixed Frequency

Smoothing
Condenser

Three-phase Motor

Power Supply

Start Command

Variable
Voltage/Frequency

Control Circuit

Frequency Command39

(2) Adoption of Natural Refrigerant
Toward reducing the Global Warming Potential (GWP), as for a refrigerant, replacing CFC’s
substitutes by a natural refrigerant, namely Isobutane, is now taking place. Isobutane is capable ofimproving cycle efficiency by approximately 7%.
Table 5: Refrigerant Characteristics
Refrigerants

CFC’s Substitutes

Isobutane

ODP (Ozone Depletion
Potential)

00

GWP (Global Warming
Potential)

1300(as CO2=1)

3(as CO2=1)

Theoretical COP (%)

100 (Baseline)

Approx. 107 (Good)A switch to the natural refrigerant has almost completed in large models of 300L or more, and its
application has been expanding to a wide range of models including small ones.
(3) Vacuum insulation material
Adoption of a combined heat insulation system of a vacuum insulation material having highinsulation efficiency and a conventional urethane insulator enables a substantial increase in heat insulation
performance.
Figure 7: Thermal Insulation Structure Using Vacuum Insulation Material
Heat-Insulated Structure Adopting <Vacuum Insulation Material>

Conventional Heat-Insulated Structure
Non-CFCfoaming
insulator

Vacuuminsulationmaterial
Outer wall

Interior wall

Interior wall

Outer
wall

Non-CFCfoaming
insulator

However, high manufacturing cost of vacuum insulation materials has now limited its use mainly tolarge refrigerators of 400L or more.

40

2-3 Differences of Method for Measuring Energy Consumption between International Standard (ISO) and
JIS Standard
A method for measuring energy consumption of electric refrigerators was set as a JIS standard (JIS C
9607) in 1979. Then in 1993, in order to ensure international compliance and repeatability, ISO standard
was adopted. In 1999, JISC9801 was subjected to partial revision due to changes in use environment andin configuration of refrigerators (shift to multiple doors), and it has been used up to the present date.
As for the international standard, it adopts a measurement method which evaluates products’
performance (cooling capability) and emphasizes its repeatability in particular.
Table 6: Transition in JIS and Its Comparison with International Standard
JISC9607 (Law A)

JISC9607 (Law B)

JISC9801

ISO8561 Standard

History ofrevisions

Established in 1979

Established in 1993

Established in 1999

Established in 1995

Ambient
Temperature

15C° (265 days)
30C° (100 days)

25C°

25C°

25C°

Humidity

75%±5%

45%～85%70%±5%

45%～75%

Installation
Condition

A refrigerator shallbe installed with theback face abutting
on wall and thesides being 30 cm
away from wall.

Same as left

Same as left

Same as left

Measurement
Condition

Nothing should be
stored in a chiller
and a freezing
compartment.

Nothing should be
stored in a chiller.
Load should begiven to a freezing
compartment.

Nothing should be
stored in a chiller
and a freezing
compartment.

Nothing should be
stored in a chiller.
Load should begiven to a freezing
compartment.

Conditioning of
Products○Chiller :3C°±0.5C°○Freezing
compartment:-18C°±0.5C°○Chiller
5C° or lower○Freezing
compartment-18C° or lower

Same as left

Same as left

○Chiller:
50 times/day
Opening/Closing○Freezingof Doorcompartment:
15 times/day
Switch off a heater
Additional
for prevention of
Functions (suchdew formation andas ice maker)
others.

No opening/closingof doorSwitch off a heaterfor prevention ofdew formation.

41○Chiller:
25 times/day○Freezing
compartment:
8 times/day
Switch off a heaterfor prevention ofdew formation andothers.

No opening/closingof doorSwitch off a heaterfor prevention ofdew formation.

Reference 4

Overview of Commercial Refrigerators, Commercial Freezers and Commercial Refrigerator-Freezers
1. What are commercial refrigerators, commercial freezers and commercial refrigerator-freezers?
(1) In Japan Standard Commodity Classification (Bureau of Statistics, Ministry of International Affairs andCommunications), commercial refrigerators, commercial freezers and commercial refrigerator-freezers(hereinafter referred to as “commercial refrigerators”) shall be defined as listed in Table 1.
(2) Refrigerators and refrigerator-freezers are classified into those for home use and for commercial use.
(For your reference)
Household refrigerators are positioned as “household electric/electronic
machinery and appliances” (Standard Commodity Classification: 60.51).
(Table 1) Medium Category 56 – Cooling Machine Applied Products and Equipment
Category No.
Product Item Name
56 3
Refrigerator-freezer equipment
56 31
Refrigerator-freezer, refrigerator and freezer
56 311
Refrigerator-freezer
56 3112
Commercial refrigerator-freezer
56 312
Refrigerator
56 3122
Commercial refrigerator
56 313Freezers
56 3131
Horizontal type freezers
56 3132
Vertical type freezers
2. Production Scale○ According to the industry statistics (Figure 1) of the Japan Refrigeration and Air Conditioning Industry
Association, actual production of 2004 is approximately 180,000 units.
(Figure 1) Transition in Shipment of Commercial Refrigerators (Unit: 1,000 units)
O-157 Special
Procurement

Annual Volume of Shipment(1,000units)

250
年
間 200
出
荷 150
台
数
100

冷凍庫

Freezers

冷凍冷
蔵庫

Refrigerator-fr
eezers（

冷蔵庫

Refrigerators

）

千
台 50
0
19 19 19 19 19 19 19 19 19 19 19 19 19 19 19 20 20 20 20 2085 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04

Source: Japan Refrigeration and Air Conditioning Industry Association421) Major manufacturers
Hoshizaki Electric Co., Ltd., Fukushima Industries Corp., SANYO Electric Co., Ltd., Daiwa Industries,
Ltd., Hitachi Air Conditioning System, Toshiba Carrier Corporation, Matsushita Electric Industrial Co.,
Ltd., Orion Machinery
2) In the 1980s, with development of the restaurant industry, shipment of commercial refrigerators increased
rapidly.
3) There was special demand due to O-157 in 1996.
4) The number of chains of convenience stores has grown since 1990, and about 170,000 to 180,000 units
are shipped every year.
3. Applications(1) They are mainly installed in hotels and restaurants (various types of restaurant industry), at offices orschools/hospitals (various types of mass feeding), and at the back of supermarket or convenience stores tostore items (See Exhibit 1).
(2) Users’ demands for commercial refrigerators differ from those for household refrigerators. Size,
specification and performance of household refrigerators cannot respond to the followings.
1) Accelerated cooling speed
Notes1. As opening and closing of a door are quite often, the function to rapidly cool down internal
elevated temperature is needed.
2. The function to rapidly cool down a hot object until set temperature is needed.
2) Enhanced thermal insulating properties
The function to maintain internal temperature at set degree even in a kitchen, etc., where ambient
temperature is high is needed.
(3) Approximately 60% of the shipment volume is made-to-order items, which are individually designed andmanufactured according to a customer’s requests. The remaining 40% are combinations of about 400
kinds of mother dice and options. They are typical products in small quantities and of various types.
(4) Mainly, food distributors and process manufacturers select configuration and performance depending on an
application. Typical configurations of a product are as shown in Exhibit 2. The followings are typicalexamples:(Example 1) Although insulation performance may become poorer, a door shall be made of glass so as toeasily understand the internal condition, thereby improving working efficiency of a worker.
(Example 2) Doors are installed on both front and back side of a refrigerator in order to have items go
through the refrigerator in one way.
(Example 3) A compressor to be mounted is selected depending on frequency of opening/closing and items
to be stored, and then cooling capability is set accordingly.

43

(Exhibit 1)
Applications of Commercial Refrigerators
Business Category
Application and Purpose
Property of Equipment
Schools
Feeding
To preserve foodstuff/food to taste Front and rear door opening/closing
Hospitals
Servicefor diet
type, cart-in typeWelfare institutions
Feeding service center
SafetyHealthcare center
To preserve food to taste for diet
Door-to-door
Transportation
To preserve delivered food
Vehicle-mounted typedelivery/postal service
Producers
To preserve mold and products
Agriculture Productive
To preserve harvestry
cooperations
To maintain chilling
Fishery
MarketTo be housed in a dedicated container.
freshness/frozen storage
Bread making
To keep and mature doughConfectionery
production
Noodle making
To preserve/mature noodles
Food
Constant temperature-high humidity
Meat processing
To preserve/mature raw
processing
type
factories
ingredients/processed items
To preserve foodstuff/To preserve
Vegetable processing
processed items and seasoning
factories
agent
HotelsGlass door type
Restaurants
Hotel bread housing typeWedding centers
Constant temperature-high humidity
Funeral halls
type
Event halls
Center pillar-less type
Golf courses
Sandwich type
To preserve foodstuff/processed
Drawer type
items
Type with rapid freezing capability
featureRestaurant
Drain water evaporation type
Business Restaurants atpassenger boats
Railroad restaurants
Buckwheat/wheat
To preserve noodle
noodle shops
ingredients/foodstuff.
Ramen shops
To preserve foodstuff such as meat,
Steak houses
vegetables, etc.
Hamburger shops
Sandwich type
Sushi restaurants
To preserve sushi items
Hospitals, elder care
Lease
To let a room with rent
Chiller locker typefacilities
Stock rooms in theback of convenience
storesTo preserve foodstuff/preserve
Sales
Stock rooms in the
goods/to preserve delivered foodback of supermarkets
Food section of
department stores

44

(Exhibit 2)
Product Configuration

1) Vertical Type・ This type is used in a kitchen in restaurants, coffee shops, ice cream shops, supermarkets, generalcafeteria, and feeding facilities, etc.

Figure a. Vertical Type (Range of Effective Internal Volume: 300 to 1,800L)(Features)・ Having larger internal volume per lot area than the horizontal type, the vertical type is used in a kitchen
in a hotel, feeding facilities, etc. installation area of which is limited. A cooling unit is mounted at the
top.
・ There are a number of demands for glass doors to maintain the visibility of stored items inside a
refrigerator.

Glass doors areavailable
depending onuser’s requests.

Product in the photograph:
Effective Internal Volume 1,042 L
Power Consumption 370 Ｗ

45

Figure b. Locker Type (Range of Effective Internal Volume: 216 to 288 L)(Features)
・ A condensing unit is mounted at the bottom. The single unit controls temperatures of all compartments.
・ As each compartment is independent and thus each door of every compartment can be opened or closed
independently, this type has better energy efficiency than other refrigerators having the same capacity.

Product in photograph:
Effective Internal Volume: 36L x 8 compartments (288L)
Power consumption 370Ｗ

46

2) Double-Sided Door Type
(Features)・ It has the same structure as the vertical type.
・ In hotels, fast food restaurants, etc., doors are installed on both front and back sides to improve working
efficiency. Food can be put in or taken out from both sides.
Figure c. Pass-through Type (Range of Effective Internal Volume: 523 to 1,800L)
Product in photograph:
Effective internal volume 1,730 L
Power consumption 1,055 Ｗ

Kitchen Side

Service Side

Possible to use from both a kitchen side anda service side.

Figure d. Cart-in Type (Width of Effective Internal Volume: 1,000 to 2,500 L)
・It has the same structure as the vertical type.
・Items can be preserved while kept on a cart.
Product in photograph:
Effective internal volume 2,413 L
Power consumption 736 Ｗ

473) Horizontal Type・A cooling unit is mounted on the side.
・ The product shall be approximately 800 mm high and a working table is provided on a top face. Thus,
internal volume per lot area cannot be increased. The working table shall be used for various cooking
tasks and temporary storage of cooked food.
Figure e: Horizontal Type (Range of Effective Internal Volume: 74 to 700L)

Product in photograph: Effective internal volume 332 L
Power consumption 220 Ｗ
Figure f. Sandwich Table (Range of Effective Internal Volume: 240 to 520L)
・Rectangle holes are provided on a top board and foodstuff containers are fitted in the rectangle holes and sealed.
Containers are chilled by cold air inside, and thus foodstuff is kept fresh.

Cold
Air

Sliding

Product in photograph: Effective internal volume

426 L

48

Power consumption 266 Ｗ

4) Other Examples
・ A cooling unit, refrigerant piping, etc. are provided for chilling and freezing in parallel, and different
temperature zones are controlled in one device.
Figure g. Refrigerator-freezers (Range of Effective Internal Volume: 330 to 1,800L)

Chilling

Freezing

Chilling

Chilling
Chilling
Freezing

Product in photograph: Effective Internal Volume 1,524 L
Power consumption 740Ｗ

49

Figure h. Constant-temperature high-humidity storage (Range of Effective Internal Volume: 290 to 1,500L)
・ The internal structure of a refrigerator is composed of dual boxes wherein cold air flows therebetween, andindirect cooling is conducted. A convective flow inside a refrigerator is thereby controlled, a face of foodstuff
is prevented from drying, and high humidity is maintained.
・ Because of indirect cooling, there is a little difference between temperature of internal air and interior wall facetemperature, and thus moisture inside a refrigerator cannot easily form dews, and humidity is maintained. In
addition, as foodstuff is not subject to wind, it does not dry easily.

Dual Wall
Cold air in space

Product in photograph: Effective internal volume 818 L
Power consumption 410 Ｗ

50

(Figure i.) Option

Example of Order-to-made Selection

Order-to-made / Options for Vertical Type
Order-to-madeOptionOrder-to-made is only available whenshipped from a plant.

Water-cooled
Unit

An option can be attached on site orwhen shipped from a plant.

Water-cooled unit
Acid-resistant specification
Suck/discharge at front
Cleaning pan
Internal lamp

Net rack set
Glass door
Deodorizing sheet
Door stopper for changing
door opening angle

Door for reversed opening
Hinge set for a door forreversed opening

Lock fixing bracket

Tray slide (nonstandard)

Tray slide

Casters
Drain Tank
Mounting of a skirt

Extension of power
supply cord

Pillar change

Twist plug
Change to three-phase
200V specification

Ever drain forcible evaporator(externally attached)

Rear stainless specification

Order-to-made / Options for Horizontal Type
Order-to-madeOrder-to-made is only available whenshipped from a planet.
Water cooled unit

OptionAn option can be attached on site or whenshipped from a plant.

Water cooled
unit

Hotel pan specification
Change of the top board shape
Right unit specification
Net rack set

Stainless steel grill specification
Cold + drawer

Deodorizing set

Internal lamp
Door stopper for changing
door opening angle

Glass door
Tray slide

Lock fixing bracket

Cleaning pan

CasterDrain tank
Mounting of a skirt
Acid-resistantspecification
Extension of power supply cord
Pillar change

Rear stainless specification

Ever drain forcible evaporator(externally attached)51