報告書番号

Y00005

タイトル（和文）

地球環境と電力化

タイトル（英文）

Global Environment and Electrification

概要 （図表や脚注は「報告書全文」に掲載しております）

エネルギーシステムの望ましい性質である「便利さ、クリーンさ、安全さ」などと調和した形で温暖化問題を解決する手段として、電力エネルギーの果たす役割を分析した。電力は多くの場合、他エネルギーに比べてクリーンである。この特徴により、温暖化対策を含めたあらゆる環境問題の解決策として、電力利用を中心に据えた持続可能なエネルギーシステムを構想することができる。この構想に関して、電力化の技術史的分析、電力化ポテンシャルの部門別評価、長期エネルギーモデル分析の３つの分析を行った。結果として、他エネルギーを電力で代替してゆく方法であらゆる環境問題に対応できる可能性が示された。温暖化対策は、電力化の持つこの可能性を、近視眼的な排出抑制を理由に阻害してはならず、むしろ汲み上げることが必要である。

概要 （英文）

The international negotiation relating to the Kyoto Protocol continues. Domestic policy measures for climate change mitigation is also under discussion. While long-term perspective is of vital importance in designing sensible policy measures, decision-makers tend to be myopically focused upon short-term reduction of greenhouse gas emissions. More attention should be paid to the fundamental change that is achievable only through the long-term process of nurturing energy systems. The requirements for the future energy systems are cleanness, convenience, and safety. The author analyzes the possible role of electricity in serving as the mainstay of such energy systems. Electricity is cleaner than other energy carriers since it is combustion-free on the demand side, while it has low emission power generation options on the supply side. Moreover, large scale centralized combustion, such as large fossil fuel power plant, contribute to better environmental quality than small and dispersed activities. The author further examined the potential role of electricity in combating global environmental problems. Three methodologies are employed. First is historical analysis of technology. Electrification has been observed as historical imperative. It has been driven by social demand to more convenience, cleaner and safer final energy. The electrification steadily continues as income increases, technology innovation continues, and environmental information diffuses. Second is by-sector analysis of ‘electrification potential’, that is the extent to which electrification pays both economically and technologically when one takes convenience, improvement of local environment, emission reduction in greenhouse gases into account. The potential is estimated with reference to contemporary Japan. Residential and commercial sector will continue increasing its electrification rate, which is already as high as 43%. Transportation sector, whose electrification rate is only 2% now, has the potential of massive electrification to meet high environmental performance required. Industrial sector will see a drastic electrification as the outcome of sensible global environmental policy for two reasons. 1) Promotion of recycle will shift the energy demand structure away from basic material production process, that is fossil fuel intensive, to other process that is electricity intensive. 2) Industrial heat pump will substitute direct combustion of fossil fuel. Third, ultra long-term energy and CO2 emission scenario is analyzed with the numeric model Energy for Sustainable World (ES). ‘Conservative climate change mitigation’ case, in which substitution to electricity is purposely restrained by policy, showed limited CO2 emission reduction. Disastrous environmental consequence is not avoidable by such a policy. In contrast, ‘Electrification and climate change mitigation’ case, in which the policy encourages substitution to electricity, turned out to be feasible and sensible since climate change is prevented while the energy systems are continuously getting more convenient, cleaner, and safer. The potential to mitigate environmental problems by promoting electrification by substituting other energy sources deserves attention. Environmental policy must not kill the electrification potential out of myopic consideration to immediately reduce emissions. Rather, the policy must encourage society to explore the potential. The environmental policy compatible with electrification is politically more feasible than simple conservation policy, since it is consistent with other policy goals for increasing the welfare.

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