Until now, as a way of reducing greenhouse gas emissions from Japanese homes, the emphasis has been on reduction of energy consumption for air-conditioning and lighting. In recent years, there has been progress in CO2
emission reduction through research into the water-saving performance of bathroom fixtures such as toilets and showers. Simulations have shown that CO2
emissions associated with water consumption in Japanese homes can be reduced by 25% (1% of Japan’s total CO2
emissions) by 2020 through the adoption of the use of water-saving fixtures. In response to this finding, a program to promote the replacement of current fixtures with water-saving toilet bowls and thermally insulated bathtubs has been added to the Government of Japan’s energy-saving policy. Furthermore, CO2
emission reduction through widespread use of water-saving fixtures has been adopted by the domestic credit system promoted by the Government of Japan as a way of achieving CO2
emission-reduction targets; application of this credit system has also begun. As part of a bilateral offset credit mechanism promoted by the Government of Japan, research to evaluate the CO2
reduction potential of the adoption of water-saving fixtures has been done in the city of Dalian, in China.