My research focus is on the nuclear energy and renewables in relation to the climate change mitigation and also to the electricity market reform in Japan. I am studying it from the law perspective. Before the Fukushima Daiich nuclear power plant accident of 2011, the nuclear energy was the most important measure to reduce CO₂ emission in Japan. However, now, it is not easy to resume the operation of nuclear power plants because the new nuclear regulatory scheme requires the old reactors to meet the present safety regulations. Also, the nuclear fuel cycle seems unsuccessful. In these circumstances, the Government is again trying to encourage the nuclear energy, using the non-fossil value mechanism. The renewables is another important way to reduce the CO₂ emission. The RPS Act of 2002 introduced the Renewable Portfolio Standard scheme, but it was not successful. After the Fukushima, the Feed-in Tariff replaced the RPS. However, in the process of the electricity market reform, a kind of RPS is coming back based on the non-fossil value requirement.