There's another approach that's been fairly successful, and cheap, in California. Demand side management via advertising/incentives. It's, so far, been cheaper to offer rebates on more energy efficient stuff (appliances, roofing, etc...) and run some commercials telling people to turn off non-essentials during peak demand in the summer, maybe turn up the thermostat a few degrees, than it is to expand electricity transmission capacity when it would only be used one two-thousandth of the year or so. W/ demand side management, for instance an on-board timer that interfaces w/ local wlan for EV charging would be dirt cheap in cities where demand would be the greatest and could charge problems. Dispatchable cuts, so to speak, are already here, it's just how pervasive they need to be given peak energy consumption compared to average energy consumption.