Are electric vehicles cleaner than combustion-powered cars and trucks or is that just an ugly rumor? We’ll answer that thorny – and complicated – question right here.
Critics castigate the cleanliness of EVs while proponents of battery-powered cars and trucks proclaim they’ll save the planet. But who’s right? We’ll lay to rest the burning question about whether EVs are greener than combustion-powered vehicles and why this is the case. The answer is indisputable, though the process of calculating it is incredibly complicated, with lots of math and analysis.
Now, before getting to the bottom of this EV vs. ICE debate, we first need to understand what’s being covered here. For this discussion, let’s focus solely on carbon dioxide emissions across a vehicle’s lifetime, that is, from manufacturing to recycling. And of course, this includes all the emissions produced while a vehicle is driven. A cradle-to-grave approach is the only way to do this comparison fairly, because it takes into account manufacturing, fuel and battery pathways, tailpipe emissions and more.
Now, to answer the bedrock question, yes, from a lifecycle carbon-emissions perspective, EVs are cleaner than ICE cars and trucks, significantly cleaner. Looking at data from the US Department of Energy, over the course of its lifetime, a 2020 model year small SUV powered by a conventional gasoline engine is estimated to produce an average of 420 grams of greenhouse gas carbon dioxide equivalents per mile driven. In comparison, a model year 2020 electric vehicle with 300 miles of real-world range is expected to emit less than half the CO2 equivalents per mile, just 206 grams. And that’s with the EV being charged using the US average power grid mix, meaning fossil fuels like coal and natural gas are used to generate electricity along with some renewables like wind and solar.
For reference, the US EPA has a nifty Power Profiler tool that lets you see precisely how electricity in your eGRID subregion is generated. For 2021, the latest data available, natural gas and coal accounted for the most power generated nationally across all 27 subregions, representing more than 60% of our electricity. But nuclear, wind, hydroelectric and solar are coming on strong. Combined, about 37% of US power comes from these sources.
Aside from data published by the Department of Energy, researchers at the Argonne National Laboratory studied lifetime greenhouse gas emission produced by both EVs and ICE vehicles. Not surprisingly, they reached the same conclusion. They compared 2020 model year cars with an expected lifetime of 173,151 miles. For their calculations, the gas model returned 30.7 MPG while the electric had 300 miles of range and was charged with power having average US grid emissions. In this model, the gasoline car produces around 375 grams of greenhouse gas emissions per mile driven over its lifetime. As for the EV, its total emissions are only around 150 grams per mile.
What’s interesting is that while over their lifetimes, EVs are far and away cleaner than ICE cars and trucks, building them is actually much dirtier, a fact critics often mention. Citing research done by the Argonne National Laboratory, MIT’s Climate Portal says that because of their battery packs, building new electric vehicles results in around 80% more emissions than producing a similar gasoline-powered car or truck; that’s obviously a huge difference. In fact, it’s estimated that assembling an 80-kWh Tesla Model 3 lithium-ion battery – just the pack – creates between 2.5 and 16 metric tons of CO2, potentially more than 35,000 pounds of carbon dioxide!
Of course, those emissions come from a range sources. You may mine for lithium or other raw materials in south America, which takes huge amounts of fossil fuel. It’s estimated that 15,000 metric tons of CO2 are released for every ton of hard rock lithium that’s mined. Those materials then might get shipped to China, where they’re refined and assembled into battery cells. Of course, that produces more emissions. Those finished components might then be loaded onto another boat and shipped across the ocean to the US, which produces loads of CO2. The cells could then take a train ride across the country to an automaker’s manufacturing plant where they finally get installed in a vehicle, which means even more carbon dioxide is emitted.
Surprisingly, this process closely mirrors the fuel pathway for gasoline. Think about it, you have to discover exploitable oil deposits, then pump the stuff to the surface, refine it, blend it and transport it, with carbon being emitted every step of the way, even before the stuff gets burned.
Over their lifetimes, gas-powered vehicles are so much dirtier than EVs because setting dead dinosaurs on fire produces loads of carbon dioxide. Here’s a fun fact for a little perspective. According to the US Energy Information Administration, when burned, a gallon of gasoline blended with around 10% ethanol produces nearly 18 pounds of CO2, so emissions add up very quickly. That is one hell of a chemical reaction.
Now, I’m not taking this into account here, but we can’t forget – it’s not just carbon dioxide. On their own, EVs emit no hydrocarbons, particulates, nitrogen oxides of carbon monoxide, none of that nasty stuff. Sure, power plants produce emissions, but it’s far easier to control a single source than millions of individual tailpipes.
If you still don’t believe that EVs are greener, here’s yet another data point. The US Department of Energy’s Alternative Fuels Data Center says that nationally, the average CO2-equivalent emissions for an all-electric vehicle are 2,817 pounds per year compared to 12,594 pounds annually for a gasoline-powered vehicle. That means internal combustion is 4.5 times worse! Naturally, hybrids and plug-in hybrids fall between these extremes.
And finally, even if electrics only lasted half as long and gas-powered cars – 90,000 miles compared to 180,000 – an MIT study still shows that EVs are still 15% cleaner than hybrids and miles ahead of comparable ICE vehicles.
So, there you have it. There’s a lot of data to digest here, but the big takeaway is that EVs are faaaaaar cleaner to own and operate than ICE vehicles, even if they can be significantly dirtier to build. With electrics, you’re basically paying for the carbon emissions up front – though a lot fewer of them – rather than over the life of the vehicle. And even if they’re not truly “emissions free,” EVs are still clearly better for the environment.
