2026-08-06 カリフォルニア大学サンタバーバラ校(UCSB)
<関連情報>
- https://news.ucsb.edu/2026/022737/thinking-about-trading-your-car-ev-theres-compelling-new-reason-do-it-now
- https://www.science.org/doi/full/10.1126/science.adv5441?af=R
完全に稼働している内燃機関車を廃車にすることによる気候変動対策上のメリット The climate benefits of retiring a fully operational internal combustion engine vehicle
J. Elliott Campbell and Roland Geyer
Science Published:6 Aug 2026
DOI:https://doi.org/10.1126/science.adv5441

Abstract
Internal combustion engine (ICE) vehicles represent the single largest source of carbon dioxide emissions for most US households. Although battery electric vehicles (BEVs) considerably reduce use-phase emissions, the transition poses a fundamental life cycle optimization challenge: Is there a net climate benefit to retiring a functional ICE vehicle before its end of life? Retiring a functioning ICE vehicle incurs a fundamental trade-off between BEV manufacturing emissions and decreased vehicle operation emissions. In this study, we evaluated this trade-off across a comprehensive range of retirement scenarios and found that scrappage-and-replacement yields consistent emissions reductions across most contexts, including the retirement of new ICE vehicles. Although scrapping a functional asset remains economically prohibitive under current market conditions, these results demonstrate a major mitigation potential for policy interventions, such as enhanced scrappage subsidies, to address the emissions of an increasingly durable ICE fleet.

