Globally, the transportation sector contributes over 20% of all greenhouse gas (GHG) emissions. Of this, the road sector accounts for more than 80%, and demand is increasing, driven by rapid urbanisation. Electric vehicles (EVs) offer a solution to meeting this demand while reducing carbon emissions from the transport sector to address climate change.
How green are EVs really in comparison to internal combustion engine (ICE) cars on a well-to-wheel basis?
Though EVs have zero tailpipe emissions, we must also consider carbon emissions from other segments of the value chain, including from vehicle manufacturing and fuel production or, in the case of EVs, power generation. To understand how the environmental credentials of EVs stack up against ICEs on a well-to-wheel basis, we evaluate the energy and material used across lifecycle stages, including well-to-pump (or charging station), pump-to-wheel, and vehicle and battery manufacturing and disposal. This is a powerful technique that allows for characterisation of the consequences of possible policy options or scientific alterations, and the development of realistic strategies for sustainable future transport.
For this purpose, we combined proprietary data on emissions associated with Upstream oil and gas operations; power sector fuel mix and emissions by country from our Energy Market Service; and refinery yields from our PetroPlan model and Product Market Service, with publicly available data from the US Environmental Protection Agency and Argonne National Laboratory.
The results of this integrated analysis were insightful. Based on the existing electricity generation mix in developing countries such as India and China, an EV can displace up to half of the GHG emissions of a gasoline ICE car. In developed countries like the US and UK, where the electricity fuel mix is cleaner, the difference is even greater.