Japan’s CO2 emissions from energy use increased for four consecutive years, reaching 1235 megatonnes in the 2013 fiscal year, partly because of the closure of its nuclear plants in the wake of the March 2011 Fukushima-Daiichi accident, the Institute of Energy Economics of Japan (IEEJ) on 11 January.
However, through the use of more renewables and the restart of some nuclear plants, as well as a fall in demand, energy-derived CO2 emissions fell to 1190m tonnes in FY14 and 1148m tonnes in FY15. The IEEJ published its Energy Outlook of Japan Through 2017 report in late December 2016.
The IEEJ expects further reductions to 1137m tonnes in FY16 and 1105m tonnes in FY17, which will bring Japan closer to achieving 927m tonnes of CO2 emissions. This will be 26% less than the FY13 level and is the target it had presented internationally for FY30. The IEEJ said five Japanese reactors had been restarted since new regulatory standards were brought in after Fukushima-Daiichi. If a cumulative total of 14 reactors are restarted by the end of FY17, as assumed in its reference scenario, the total generated electricity from nuclear will be 62.9TWh, down from around 288TWh in 2010, before the Fukushima-Daiichi accident.
However, in its "low-restart" scenario, if only seven reactors are restarted by the end of FY17, in comparison to the reference scenario, total fossil fuels will increase by JPY300bn ($2.6bn), the cost of electricity by JPY0.2/kWh and energy-derived CO2 emissions by 16m tonnes.
Under the "best mix" scenario – which reflects the generation mix of the Ministry of Economy, Trade and Industry's long-term energy supply and demand outlook – nuclear power "will play an important role in achieving the 3E's (energy security, economy and environmental protection)". Under this scenario, nuclear output reaches 195TWh by the end of FY2017, the cost of electricity increases by JPY0.5/kWh, imports of fossil fuels decrease by JPY1200bn and energy-derived CO2 emissions fall by 101m tonnes.