The economic cost in the electricity sector in Japan, Post-Fukushima

Of the 30 countries that use nuclear energy, Japan was the third country with greater number of nuclear reactors and installed capacity; there were 54 nuclear reactors with an installed capacity of 46,343 MW, and the participation of the nuclear energy in the electricity generation of the country was of 33% in 2010. The Fukushima accident of March 11, 2011 due to natural forces not foreseen and with a very low occurrence probability with characteristics outside the design base, provoked questioning of the safety measures of the others 51 nuclear reactors that operated in Japan. This situation causes that the mentioned 51 nuclear reactors remain without generating electric power until to ensure its safety operation before the new risk conditions. Particularly, the Japanese electric system had combined cycle plants based on gas which were used of way load pick and backup that before this new situation, they must operate as base load sources. For Japan, the nuclear energy was a base load source reliable and economic since Japan does not possess enough own resources for its electricity generation. The market of the natural gas in Japan is at present one of the most expensive worldwide so that impacts negatively in the electricity generation cost. This work analyzes the measures taken to cover the loss of nuclear electricity generation, basically by means of the use of the combined cycle plants based on natural gas, and the impact that these measures had in the costs of electricity generation of the Japanese electric system. The obtained results in this analysis show that the national electricity generation cost was increased and collaterally the quantity of greenhouse gases emissions of the country also increased. (Author)