A question that often comes up about electric vehicles (EVs) is “how clean are they really?” While EVs have no emissions at their tailpipe, they do require energy, and that energy has to come from somewhere. How clean a particular EV is depends on the form of electricity that powers it. In the U.S. we rely on a wide range of electricity sources including natural gas, coal, nuclear, hydroelectric, wind, solar, biomass, and geothermal. Where you live largely determines what sources are used to generate your electricity.
Figure 1. Percent Greenhouse Gas Emissions Reduction for an EV vs. Average Vehicle
We used a tool from the US Department of Energy to compare the emissions of an EV to the average conventional vehicle for each state to generate the map in Figure 1. Click on your state to find out how clean EVs are in your state and compare with other states around the country. We found that in all states, EVs generate fewer greenhouse gasses than the average gasoline powered vehicle by at least 20%. This was true even in states that heavily rely on coal to generate their electricity like West Virginia and Kentucky. Nationwide EVs are over 60% cleaner than the average gasoline powered vehicle. In the future this will only get better as older, dirtier coal plants are replaced by more and more cleaner sources of electricity.
|In addition to reducing greenhouse gas emissions, EVs can also help reduce the air quality impacts of harmful criteria air pollution, such as NOx, ozone, and particulate matter, that are known to create smog and can cause lung diseases. The effects of EVs on criteria pollutants are two-fold:
If you want to learn more about whether going electric is right for you, check out CR’s Electric Cars 101: The Answers to All Your EV Questions.
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