Comment on ‘Reappraisal of paths to decarbonising British electricity generation in 2030’

Abstract

Electrifying transport and heat are central to climate change mitigation, as electricity is unequivocally lower carbon than burning fuels in cars, boilers and furnaces. In a recent paper, Dunstan and Drew argue that expanding electrification before complete power-sector decarbonisation yields no proven emissions savings, because the additional load from electric vehicles (EVs) and heat pumps (HPs) will be provided entirely by gas-fired power stations. We show that these claims rest upon simplifying assumptions about carbon accounting and power system operation, and mis-specified efficiencies for gas power plants, vehicles, boilers and HPs. When using empirically-grounded efficiency data, we show that even if HPs and EVs were powered solely by gas-fired power stations, they would use half as much fossil fuel as modern gas boilers or combustion-engine vehicles. We then explain how the British power system uses a mix of sources, so additional demand from electrification is met by energy storage, interconnection and demand-side response, alongside flexible power stations. Even without being ‘completely decarbonised’, the short-run marginal carbon intensity of British electricity is half that of unabated natural gas, and the mean carbon intensity is two-thirds lower. Our findings and the wider literature demonstrate that electrification benefits scale with electricity’s carbon intensity and contradict Dunstan and Drew’s zero-savings headline. Clarifying these basics is important for policy and public trust, because today’s purchases of long-lived vehicles and heating systems can lock in fossil-fuel dependency and continued carbon emissions for decades.