Do We Charge Our Electric Vehicles with Coal or Solar?

A colleague from Northern California read my recent post on electric vehicles in which I wrote: The fact that, at this point, EVs are almost always charged by burning more coal, rendering their environmental benefit dubious at best.

He comments:  How can you say that, Craig? 

In CA, with the largest numbers of plug-ins, somewhere between 1/3 and 1/2 of owners have PV, almost none of our electricity comes from coal and even for the country as a whole coal is less than half the mix. Plus they are the route to zero carbon, as the grid gets cleaner and more sustainable, which is our only option to combat climate change.

That said, 45% of EV owners having solar is not equivalent to saying that they charge their cars with solar.  The latter is obviously possible; I know people who do it, but it requires a real commitment of dollars and inconvenience, and I seriously doubt that anywhere near that percentage of people do it.  And keep in mind that we’re talking about California, where most people actually care about this stuff.

True, California doesn’t burn coal, but we buy power from and sell power to states that do.  As long as coal is the “go-to” source of baseload power in the U.S., grid operators are obliged to seek it out and use it.  This means that adding an incremental load to the grid at night means that someone somewhere is burning more coal.  This will be true regardless of how clean the grid gets on average; the average grid-mix is irrelevant to this.

As I’m sure you read in the remainder of the post, I still have many (was it eight?) reasons to favor EVs.