Abstract: An integrated scenario analysis has been conducted toward zero-carbon energy system from 2010 to 2100 in Japan, wherein the effect of Fukushima nuclear accident happened in March, 2011 is more or less taken into account. In the study, various service demands are firstly estimated based on social-economic data and then best technology and energy mixes are obtained using the optimization model to meet the service demand. On the conductance of integrated scenario analysis towards the year 2100 when zero-carbon energy system will be attained, three different scenarios of nuclear power development are taken, i.e., (i)no further introduction of nuclear, (ii) fixed portion and (iii) no limit of nuclear. The results show that, in the end user side, zero-carbon energy scenario can be attained at 2100 with electricity supplies 75% of total energy utilization. And for the electricity supply, three different power generation scenarios are proposed: (Scenario 1) 30% renewable and 70% gas-CCS(Carbon Capture and Storage), (Scenario 2) every one third by nuclear, by renewable and by gas-CCS, and (Scenario 3) 60% nuclear power, 20% renewable and 10% gas-CCS. Lastly by the inter-comparison of the three scenarios from the four aspects of cost, CO₂ emission, risk and diversity, Scenario 2 is rated as the most balanced scenario among the three by putting emphasis on the availability of diversified electric source of nuclear, renewable and gas-CCS.

Keyword: zero-carbon energy system, scenario analysis, nuclear power