Are electric cars less polluting than cars using fossil fuels?

Since they were introduced to the mass market a few years ago, I was convinced that EVs (electric vehicles) are much more friendly for the environment than vehicles with conventional internal combustion engine vehicles (ICEVs). When I had a discussion at work last year about the merits of EVs with a colleague, I desired to show him evidence for my claim. I found this 2013 study which compared the lifecycle environmental impact of EVs with ICEVs. The summary of this study reads as follows:

We find that EVs powered by the present European electricity mix offer a 10% to 24% decrease in global warming potential (GWP) relative to conventional diesel or gasoline vehicles assuming lifetimes of 150,000 km. However, EVs exhibit the potential for significant increases in human toxicity, freshwater eco-toxicity, freshwater eutrophication, and metal depletion impacts, largely emanating from the vehicle supply chain. Results are sensitive to assumptions regarding electricity source, use phase energy consumption, vehicle lifetime, and battery replacement schedules. Because production impacts are more significant for EVs than conventional vehicles, assuming a vehicle lifetime of 200,000 km exaggerates the GWP benefits of EVs to 27% to 29% relative to gasoline vehicles or 17% to 20% relative to diesel. An assumption of 100,000 km decreases the benefit of EVs to 9% to 14% with respect to gasoline vehicles and results in impacts indistinguishable from those of a diesel vehicle. Improving the environmental profile of EVs requires engagement around reducing vehicle production supply chain impacts and promoting clean electricity sources in decision making regarding electricity infrastructure.

The following passage is more specific on the impact of the fuel sources used to generate electricity for EVs:

For all scenarios analyzed, the use phase is responsible for the majority of the GWP impact, either directly through fuel combustion or indirectly during electricity production. When powered by average European electricity, EVs are found to reduce GWP by 20% to 24% compared to gasoline ICEVs and by 10% to 14% relative to diesel ICEVs under the base case assumption of a 150,000 km vehicle lifetime. When powered by electricity from natural gas, we estimate LiNCM EVs offer a reduction in GHG emissions of 12% compared to gasoline ICEVs, and break even with diesel ICEVs. EVs powered by coal electricity are expected to cause an increase in GWP of 17% to 27% compared with diesel and gasoline ICEVs.

A conference paper from 2010 reaches a similar conclusion and supplies some illustrative graphs for those of us who are more visually inclined. The 2013 study was given a spin by some news media to write clickbait articles which portray EVs as more destructive to the environment than ICEVs. That obviously does not follow from the conclusions of the study: EVs are better for the environment if powered by the average European electricity mix, but worse if they are powered by electricity generated with coal. This is also the emphasis of Greenpeace. According to other research from the USA, EVs are better for the environment than average ICEVs, even if the dirtiest electricity mix in the USA is used.  There has been some criticism from the the pro-EV camp as well: due to flaws in the 2013 study it overstated the environmental impact of EV production.

I started wondering, what is the average European electricity mix? In the data supplied with the 2013 study the electricity mix data is referenced to be in the final tab of the spreadsheet, but that tab doesn’t exist. Even so, we can use the data from Eurostat for 2012 (figures converted from GWh to TWh):

Oil Coal and lignite Gas Nuclear Renewables Other fuels Total
72 892 615 882 798 35 3.295
2% 27% 19% 27% 24% 1% 100%

Compare this with the data on the electricity mix for the Netherlands in 2012 from Statistics Netherlands. I converted the data from MWh to TWh. Eurostat should have this data for the Netherlands in the same table they use in their data visualization I referenced in the previous paragraph. However, I can’t figure out how I can distill the same figures from that data as they give in the visualization. The data from Statistics Netherlands and Eurostat doesn’t match exactly so I had to modify the categories, that’s why the total in the Dutch data is 96%.

Oil Coal and lignite Gas Nuclear Renewables Other fuels Total
0,03 24 54 4 13 3 103
0% 24% 53% 4% 12% 3% 96%

The data shows that nuclear and renewable energy constitute a much smaller share of the energy sources used in the Netherlands. Gas is a much more important source. On the other hand coal is used slightly less. Gas is cleaner than coal, though not as clean as nuclear power (considering only emissions) or renewables. Not desiring to make further intricate calculations myself, I’d assume that the electricity mix in the Netherlands is clean enough to make use of EVs preferable over ICEVs. Of course it’s imperative that we invest much more in renewable energy, because our current percentage of 12% is an embarrassment.

Even so, producing all those EVs would demand a lot of resources. Also consider that EVs with seats for five persons, like ICEVs currently, will often be used by just a single person to commute to work. We keep the problem of traffic congestion as well. This is inefficient when compared to public transport, which should still be a preferred investment.

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