Each country usually has a wide range of products on the market, with EERs varying from low to high efficiencies. For example, the average EER in Japan is at 4.1, but available products can have EERs as low as 2.5 and as high as 6.5. Japan’s average EER is exceptionally high, compared for example with the EU’s average of 3.1.
In general, the best available products in developed countries have higher EER than in developing countries. However, differences in the average of available products or in the least efficient products are small.
Over the last decade, there was relatively little improvement in EERs. China is an exception, with a significant EER increase in the least efficient products from 2.3 in 2005 to 2.9 in 2011, concurrent with the introduction of MEPS.
The reason for comparably high EERs in Japan and China is the high penetration rate of inverter technology.