Electric vehicles (EVs) are seen as a sustainable alternative to cars with a traditional internal combustion engine. However, there are concerns about the impact of the supply chain, which would not be clean. However, even if indirect emissions are included, EVs are significantly cleaner than traditional vehicles.
This is according to research by US Yale University. The researchers publish their findings in Nature Communications. The indirect emissions are separate from the direct emissions created by burning fossil fuel. They include emissions in the supply chain for components of EVs. And emissions from generating electricity for EVs.
The research was conducted by a team from Yale University led by then graduate student Paul Wolfram. The team also included PhD Stephanie Weber, economics professor Ken Gillingham and industrial ecologist from the Norwegian University of Science and Technology Edgar Hertwich. The team combined concepts of energy economics and industrial ecology in their research. Including CO2 charging, lifecycle management and energy systems modelling. The study aimed to identify whether CO2 emissions from EVs are still lower if the supply chain is also included. This indeed turns out to be the case.
Creating a level playing field
"A major concern about electric vehicles is that the supply chain including mining, raw materials processing and battery production is far from clean," Gillingham explains. "If we put a price on the CO2 released in these processes, the expectation was that EVs would be exorbitantly expensive. This turns out not to be the case. If you create a level playing field by also putting a price on the CO2 emissions from the supply chain for fossil fuel-based vehicles, EV sales would actually increase."
"The supply chain for combustion vehicles is simply so polluting that EVs cannot overtake them. Not even if you include indirect emissions," says postdoctoral associate Stephanie Weber.
Emissions from EVs are expected to decrease
The researchers foresee that indirect emissions from EVs will decrease over time. Future technological developments are expected to play an important role in this. If, for example, electricity is generated in a cleaner way, this could significantly reduce indirect emissions. As a result, the difference in emissions between EVs and traditional vehicles is expected to keep increasing in favour of EVs.
The study is based on US figures. The research team collected data through the US Energy Information Administration's National Energy Modelling System (NEMS). This models the entire US energy system based on detailed data. It also includes an outlook for the energy system of the future. The NEMS has been used to map how CO2 taxes on indirect emissions, among other things, can influence customer and manufacturer behaviour.
Elephant in the room
Based on the research, Wolfram concludes that it is not so much the EV production chain that is the elephant in the room, but rather the production chain of traditional vehicles. Wolfram therefore concludes that the faster we switch to EVs, the better it is. According to the researcher, this applies to all countries that have sufficient clean energy production.
Author: Wouter Hoeffnagel
