電力小売自由化を背景とした教育機関の電気事業者選択 : 京都女子大学のエネルギー消費と温室効果ガス排出量分析から

Abstract

我が国のエネルギーシステム改革が段階的に進められている中、需要家はさまざまな電気事業者から購入先を選択することが可能となっている。電気事業者の選択は、最終的には電源構成やそれに付随する温室効果ガスの排出量に関係するが、そのような帰結を教育機関はどのように判断すべきであろうか。本稿は、京都女子大学を例にとり、その過去3年間の電力・ガスの使用量及び支払額の実績を把握し、年度別の温室効果ガス排出量の算出等を行った。また、電気事業者を仮に変更した場合、温室効果ガス排出量がどのように変化するのか検討を行った。 Production of energy from non-renewable sources produces carbon dioxide, which is a main contributor to climate change. Among the users of energy, universities share a significant portion of responsibility, as they accommodate a great number of students and staff at daily basis. Yet, it is still a marginal exercise to analyse energy consumption level at universities in Japan, not to mention the identification of carbon emission volume at their campuses. In general, there is a lack of awareness among the university administration to relate their energy data and the carbon inventory, and establish strategies to reduce overall carbon emission volumes. On one side, a window of opportunity is widening in Japan, where its energy market is currently undergoing a liberalization process. Electricity market reform, broadly initiated since 1990s, was further developed in 2016, when the market became fully opened for retail competition. It means universities can purposefully choose their electricity suppliers based on their emission factors. This research analyzed the energy consumption volume of Kyoto Women’s University, Japan, as a case to identify the energy consumption and the associated carbon emission volumes, then to see how much emission reduction is feasible if the electricity suppliers with less emission factors substitute the existing contracts.