Clarkson and others always ask the question, ‘where does the electricity come from?’
There are other stats that say it’s only better after a certain amount of miles driven or that the Lithium quarries produce significant amount of pollution.
What and where do these claims come from, how true are they and how false are they?
In: Engineering
I did the rough math for my own car.
It certainly “costs more”, environmentally, to manufacture the electric car. Internal combustion cars are metal, plastic, glass, pretty basic stuff. Electric cars have more mined metal, more heavy metals for sure, and more complex chemistry going on in them.
However, thermodynamically, internal combustion engines ([Otto cycle](https://en.wikipedia.org/wiki/Otto_cycle) engines) have limits to how much energy they can extract from the gasoline. The two big areas of inefficiency is that, if you compress the air/fuel mixture too much, it can autoignite because the air gets hot under compression (this is “knock”) and when you exhaust the hot air at the end of the cycle, you didn’t expand the cylinder to infinity, thus pulling all the heat out of the exhaust (in other words, the exhaust is still hot and carrying heat energy). They have to be small and powerful and not too heavy.
The generators used in combustion power plants ([Rankine cycle](https://en.wikipedia.org/wiki/Rankine_cycle) engines) are designed differently and have different limits – for instance, you don’t exhaust the working fluid (steam), you circulate it in a loop, and can extract much more heat out of the steam because you have a whole power plant full of equiment to work with. We use this cycle in power plants *because* it’s more efficient and we’re not limited to size constraints.
So, roughly, power plants are approximately twice as efficient as internal combustion engines – this isn’t due to what they’re burning, but from how effectively they extract the power. In other words, if you took the gas out of your car and burned it in a power plant you’ll get roughly twice the amount of power out of the same gas.
So that’s something to keep in mind that often gets glossed over. Even with transmission losses and conversion between gasoline to steam to electricity to motive power, it would *still* be more efficient to burn the gasoline at a power plant to fuel your electic car, let alone how much better you can capture the greenhouse gasses and scrub the emissions.
All of that to say, I live in California, and roughly 50% of my power is from hydro, solar, and wind. And I think some nuclear? (I consider nuclear to be quite green). And gas can be quite expensive here, and electricity is… reasonable-ish.
Environmentally, my car “broke even” in about a year; cost-wise, it was more like 2.5-3 years before the cost savings of cheaper fuel outweighed the sticker-price premium for a more expensive car.
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