This assumes the cars are plugged in when there is the most 'extra' capacity being generated from , say, solar thermal/pv. This is when most cars are out at a w

This assumes the cars are plugged in when there is the most 'extra' capacity being generated from , say, solar thermal/pv. This is when most cars are out at a workplace, not plugged in. This is also when industrial consumption/ac use peaks, so why would you over produce and feed a battery rather than run a plant/keep places cool...