E-Retrofits Could Speed Up European Bus Electrification

Researchers at Empa in Switzerland determined that retrofitting diesel buses with electric drivetrains could accelerate the full electrification of Europe’s bus fleet by 15 years. Currently, even with only new zero-emission buses registered from 2035, Europe won’t reach 95% bus fleet electrification until 2057 due to the 20-year average lifespan of existing vehicles.

E-retrofitting involves replacing only the engine, gearbox, fuel tank, and exhaust system, reusing the bus’s body, chassis, and interior. This approach reduces greenhouse gas emissions, with each retrofitted vehicle saving approximately 58 tonnes of CO₂ equivalents.

The study indicates that retrofitting is cheaper than purchasing new electric buses, potentially lowering total bus transport costs by 2.2% to 3.2% by 2100. While the findings are largely theoretical due to limited large-scale programs, the researchers suggest that 1% of Europe’s automotive mechatronics workforce could retrofit 75,000 buses annually. Policymakers must now adapt funding schemes to support retrofitting initiatives.