Electric Transportation Confers Environmental Benefits, But It’s a Tricky Subject
A friend sent me this piece from the Wall Street Journal on the environmental benefits of electric transportation, called Are Electric Cars Really Better for the Environment?While it’s very good, the situation is actually a bit more complicated than this. These guys make the same mistake almost everyone makes in these calculations, i.e., they talk about the average grid mix. It’s true that the average grid mix is getting steadily cleaner, but that’s not the point. What matters is how utilities respond to a predictable, incremental load, e.g., charging a car.
In the Eastern part of the U.S. at night, sadly, this means burning more coal. You plug your car in, and you’re setting off a series of buy/sell transactions the result of which is that somewhere, somebody who would otherwise be able to throttle back coal due to the lower nighttime demand can’t do that, because he needs that incremental power. And, because coal is far dirtier that anything else, the environmental benefit of an EV charged under these circumstances is far less than other places and times, where the energy source might be natural gas, or better yet, renewables or nuclear.
This too is changing all the time, and for the better. People are actually over-building the solar PV arrays on their roofs so as to accommodate charging their cars. The carbon footprint in this case is virtually zero–it’s just the construction of the solar panels.
