It is very interesting. Basically what I did in my thesis was to try to calculate it for a residential building with shared parking, but it can be extrapolated to several other things.

The basic idea is: An EV battery is just a battery and cars are parked around 95% of the time, so why not use its battery as just a battery in that time. So the premise was: Residential electricity usage reaches its peaks in the morning when everyone is getting ready, and then late afternoon and dinner time. If everyone is at home, cars are parked and can be plugged in. So instead of purchasing costly electricity, you could use some of the energy stored in the battery. And then charge the battery at night when electricity is cheaper.

This could help maximise solar during the day, because it’s obviously when more is produced and can be wasted and during the night with wind for example. A concern of the thesis is that this would of course use the battery more which comes at a cost. I found it to still be cost efficient giving a share enough of EVs in the buildings I was studying. (I gotta say this is the shadiest part of the thesis because I simply did not have enough battery degradation data to do a proper analysis).

A lot of the peak electricity is provided by gas, because it’s easily dispatched, and so those emissions could be saved. Additionally, you could increase the amount of renewable generation, because you could store the excess during the days in the batteries of the cars.

And that was the idea, charging batteries when renewables produce more, and use the batteries instead of gas or other oil (which is barely used already).