Revisions of the Notification of the Ministry of Economy, Trade and Industry (METI)  
under the Act on the Rational Use of Energy  
 
Energy Efficiency Division 
Agency of Natural Resources and Energy  
Ministry of Economy, Trade and Industry  
 
1. Background  
Under the Act on the Rational Use of Energy (Law No. 49 of 1979; hereinafter referred to as 
the “Energy Efficiency Law ”), the Minister of Economy, Trade and Industry  shall es tablish and 
publicize standards  for manufacturers/importers  (hereinafter referred to as the 
“manufacturers, etc.”) , with regard to the improvement of the energy efficiency performance 
for the respective equipment  which is specified in  the Cabinet Order under the Energ y 
Efficiency Law  including electric water heaters .  
The Minister also shall specify the matters to be labeled  by manufacturers, etc. with regard 
to energy efficiency of specified equipment including electric water heaters.   
In addition, the energy efficiency standards shall be established taking into consideration 
the highest level of energy consumption performance of the respective spec ified equipment 
and other related factors (called the "Top Runner Program").  
The Minister propose s new energy effi ciency standards for electric water heaters to 
promote rationalization of energy use pertaining to electric water heaters in Japan in order 
to cope with the recent increase of energy consumption in the household sector, climate 
change, and so forth.  
 
2. Outline of amendment  
(A) Scope  
Electric  water heaters  
 
(B) Energy consumption efficiency and measurement method 
The energy consumption efficiency of appliances is  to be evaluated in the measurement 
method that is set forth in the “ Electric  water heater s in the household sector ” (JIS C 
9220: 2018).  
 
(C) Target fiscal year  
The target fiscal year is FY2025. 
 
(D) Category and targeted standard value  
The categor ies and targeted standard value are as follows.  
 Table. Targeted standard  value  for electric water heaters  
Category  
Name  Presumed  
Household  Number of 
storage 
tanks  Storage capacity  Specifications  Targeted 
standard value  
A 
Small family  ― ― Other than cold region 
specifications  3.0 
B Cold region 
specifications  2.7 
C 
Standard  One Less than 320 
liters  Other than cold region 
specifications  3.1 
D Cold region 
specifications  2.7 
E 320 liters or 
more 
Less than 550 
liters  Other than cold region 
specifications  3.5 
F Cold region 
specifications  2.9 
G 
550 liters or 
more  Other than cold region 
specifications  3.2 
H Cold region 
specifications  2.7 
I 
Multiple  ― Other than cold region 
specifications  3.0 
J Cold region 
specifications  2.7 
 
(E) Method to determine achievement  
The manufacturers of appliances  are required to keep the h armonic mean s of the energy 
consumption efficiency of appliances  shipped in each fiscal year after the target fiscal year,  
which is w eighted  with the number of units shipped for each  category , at the same level or 
higher than the  targeted standard value.  
 
(F) Labeling requirement  
These revisions include requirements that manufacturers , etc.  should indicate on their 
catalog s with regard to energy consumption efficiency etc.  
 
3. Proposed date of entry into force  
Around May  of 2021*  
*Target fiscal year for achieving the new standard is set to be FY2025.