350kW is about 1800 m^2 of PV panels; you need twice that plus a battery bank to operate at night. You might want a grid tie only so you can do net metering. At current prices for Chinese panels (not counting the Trump tariff) that's on the order of a million dollars. Now double that to pay for the electronic chargers themselves. So $2 million in capital costs and no recurring costs except maintenance. That's almost certainly cheaper to build and permit and operate than a petrol station, and those seem to pop up everywhere.

I don't think it will take more than a couple of years for well-maintained superchargers to be ubiquitous, and that's if you give away the power for free with government subsidies. If you charge customers for the energy, it might happen even faster.