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System Analysis of Japanese Renewable Energy

Research Fellow, Economic Research Centre, Fujitsu Research Institute (FRI), Hiroshi Hamasaki
Partner, KanORS Consultants, Amit Kanudia


Nuclear power generated more than a quarter of Japan’s electricity over the past few decades. The Fukushima disaster eroded people’s confidence in nuclear to the extent that all nuclear plants may be forced to shut down by the end of 2012. Maintaining a steady electricity supply at reasonable prices is the primary challenge the country faces today. Among the energy issues facing Japan, energy independence and carbon emissions are two important policy targets. Japan imports most of its fossil fuels and its energy self-sufficiency rate is a mere 4% (18% if nuclear power is included). The Japanese government aims to increase the self-sufficiency rate from the current 18% (including nuclear) to as much as 40%. In addition, the government has GHG mitigation targets of 25% below 1990 levels by 2020 and 80% by 2050 . Before the earthquake of March 11, 2011, nuclear was expected to play a major role in achieving energy self-sufficiency and carbon mitigation targets by increasing the availability factor to about 90% and building 14 new nuclear power stations. After the earthquake and the accidents at the Fukushima Dai-ichi nuclear power station, nuclear has become an unacceptable option. Hence, renewables are expected to play a major role. The Japanese electricity system is comprised of 10 grids with very limited inter-connection. Further complicating matters is the fact that 3 grids use 50Hz and 7 grids use 60Hz. The uniqueness of Japan’s electricity market and the instability of a renewable-generated electricity supply will be big burdens to making the most use of renewable potential in Japan. The objective of this paper is to characterise the renewable potential in Japan and to study its interactions with competitors under some key policies and technology scenarios.

System Analysis of Japanese Renewable Energy [1,507 KB]