報告書番号

Y08001

タイトル（和文）

CO2大幅削減に向けた需要側対策に関する考察

タイトル（英文）

An analysis of demand side measures towards a large-scale reduction of CO2 emissions

概要 （図表や脚注は「報告書全文」に掲載しております）

「美しい星50」提案(2007年5月) や洞爺湖サミット開催(2008年7月)などを受け、CO2排出の大幅削減に向けた長期的戦略に関する議論が活発化している。電気利用技術については個別の技術評価がなされてきたが、日本全体の合理的な削減戦略のあり方や、2050年の削減可能性について、幅広い将来像をとらえた明確な検討はなされてこなかった。
そこで本稿では、エネルギー需要側対策の方向性についての議論に資することを目的として、最終消費部門に関して、エネルギー需要それ自体の水準、および技術選択の二点について幅のある将来を仮定し、2050年のCO2削減可能性を試算した。

概要 （英文）

This study attempts to draw a rational overview towards 2050 of demand-side measures which is a key factor in significantly reducing CO2 emissions in Japan. It is well known that electrification of final energy uses plays an important role to mitigate CO2 emissions through curbing fossil fuel consumption. Electrification of thermal demand by high-efficient heat-pump technologies is considered as a realistic example, while electric vehicles including plug-in hybrid vehicles are getting higher expectations as an alternative in the transportation sector. It is of crucial importance, therefore, to analyze the potential of CO2 emission reductions by these measures and thereby to portray their roles in a viable long-term strategy. We employed detailed bottom-up calculation of Japan's final energy demand matched with a simple supply-side consideration, focusing on two demand-side factors that could essentially affect CO2 emissions; changes in energy services in the end-use sectors, and customers' technology choices. The result shows that not only is electrification a vital measure to reduce CO2 emissions under the carbon intensity of power generation kept at the current level, but that it becomes even more effective with improved carbon intensity in the future. In contrast, possibility of a deep cut of CO2 may be substantially shaved if appliances by direct combustion technologies remain to be used widely. In order for combustion technologies to be compatible with a low carbon society, they should be coupled with uses of renewable energy sources as alternative fuel and carbon capture in the industrial sector, both of which are facing a variety of challenges. Furthermore, while improving the efficiency of demand-side energy use contributes to the emission abatement, it alone cannot ensure a large-scale CO2 reduction, e.g. 50 percent cut in 2050 from 2000 level, since it is driven by the uncertainty of socioeconomic conditions.

報告者

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