Electric vehicles for low-carbon transport

Abstract

There are three main energy options for decarbonising road transport: biofuels, hydrogen and electricity. While the ‘hydrogen economy’ and fuel-cell vehicles (FCVs) are often seen as the only viable long-term option, and liquid biofuels as the only short/medium-term option, the potential for battery-dominant electric vehicles (including ‘plug-in’ hybrids) charged by low-carbon electricity has tended to be neglected in recent policy debates. However, even if low-carbon hydrogen were available it is likely to be as efficient to convert it to electricity for battery electric vehicles and plug-in hybrids as to use it for FCVs. Low-carbon electricity (e.g. from renewables, nuclear) is more efficiently used directly in electric vehicles than via conversion to hydrogen. Electric vehicles also generally have less challenging technical, infrastructural, financial and commercial barriers. In particular, the electrification of road transport can ‘piggyback’ on existing grid and off-peak generation capacity as well as market-driven R&D on advanced batteries and other electric drive components. Electricity production is also a highly efficient route for using a wide range of biomass materials in transport. Adding carbon dioxide capture and storage would give a further negative carbon dioxide emission of about 125 g/km to set against other lifecycle emissions.