Energy security in East Asia under climate mitigation scenarios in the 21st century

Japan, China, and South Korea depend heavily on imports for most of their energy. This study aims to investigate how energy security in these three East Asian countries will change in the future under climate mitigation policy scenarios. The study will help researchers and policy makers to better understand the relationship between climate and energy issues that will arise in relevant policy discussions. The analysis was conducted using a computable general equilibrium model. A reference scenario and two policy scenarios based on the Representative Concentration Pathways adopted by the Intergovernmental Panel on Climate Change are analyzed and compared between primary energy, fossil fuels imports, and diversification of energy sources. The findings suggest that to reduce greenhouse gas emissions, the three East Asian countries need to shift their energy structures from currently dominant fossil fuels to renewables and nuclear power. The lower the target of allowable emissions, the larger the required shifts will have to be. Among fossil fuels, coal use in particular must significantly decrease. Such structural shifts improve energy self-sufficiency, thus enhancing energy security. However, the impact of diversification of energy sources (measured by the Herfindahl index) under climate mitigation scenarios differs by country and scenario. Until 2050, diversity improves in all three countries relative to the base year. After that, in some countries the diversity should decline because of high dependence on a specific energy source. Overall, it is revealed that energy security improves along with climate mitigation. This improvement will also contribute to the economy by reducing energy procurement risks. •An energy security issue in three East Asian countries is analyzed.•A CGE model is used to analyze the reference and two RCP-based policy scenarios.•Primary energy demand, energy imports, and diversity of energy are investigated.•Herfindahl index is applied as a metric for diversity of energy types.•Energy security improvement is achieved simultaneously with climate mitigation.