TOKYO -- Japan once led the world in energy efficiency but now trails far behind Britain and other European countries if one looks at economic output per unit of energy consumed.
Japan has lowered its greenhouse gas emissions by about 10% over the 30 years through 2020, but the reduction mostly came from slow economic growth and a shrinking population rather than improvements in energy efficiency, as happened in the U.S. The U.S. and Europe have achieved both decarbonization and economic growth by promoting renewable energy. Economic stagnation and policy disarray have left Japan unable to do the same.
