I have seen two articles recently (Wired & CleanTechnica) that both reference research performed by the Union of Concerned Scientists that looked not just at the emissions on the road for the two types of vehicle, but the entire emissions over the lifetime of the car from manufacture onwards.
The short answer is that over their lifetime, EVs produce far less emissions than their gas powered equivalents. While the manufacturing for an EV does produce more emissions than manufacturing a gas powered car, those differences are quickly nullified by the far lower driving emissions. Just how quickly depends on the range of the EV (shorter range ones have lower manufacturing emissions than longer range ones), and where in the world the car is charged. Within the US, states that get more of their electricity from renewable sources will offset those manufacturing emissions much faster than the states that still rely on coal and gas for much of their power.
The final conclusion: on average in the US, EVs generate half the emissions of their gas powered equivalents over their lifespan. That’s a big difference. Even when most of the electricity used to charge an EV is generated by burning coal, the EV still generates less emissions than gasoline burning cars do.
End of Life
At the end of their life, the energy required to dispose of them is roughly the same, however the batteries in the EV can be repurposed (e.g. into energy storage battery packs), or recycled into new batteries. Either path should help reduce the impact of disposing of an EV even further.
Cleaner Every Day
Something that is unique to EVs is that they have the potential to get cleaner every day. Unlike gasoline cars which, if anything, get slowly less efficient over their lifetime, an EV has the potential to generate less and less emissions over its lifetime as the upstream generation technology used to produce the electricity used to charge them becomes cleaner. Despite the efforts of the fossil fuel industries to push us back to coal, oil or gas instead of using renewables, the economics just don’t stack up in their favor. As a result, even in the US, the trend is towards electricity generation becoming cleaner and cleaner. That means even those old EVs are responsible for less and less emissions.
Countering the Myth
The myth that EVs are dirtier than, or at least as dirty as ICE vehicles has been spread by the fossil fuel industry, terrified that they are losing one of their largest markets. This research proves that their claims are lies, and very likely they are well aware of that. Now the data is out there: EVs are cleaner, and unlike ICE vehicles they get cleaner every year – even the older ones that are already on the road.