To solve this issue people need to charge their cars at home with solar power.
To solve this issue people need to charge their cars at home with solar power.
If everybody switched to electric cars tomorrow, electricity use would go up about 30%. This is far from trivial, but it's not the sort of thing that would cause prices to spike.
Answering the grandparent, payment varies. At home, you obviously just pay it in your electric bill. When charging away from home, some chargers are free. Businesses often put them in to attract customers, and Tesla operates a vast network of chargers whose operating costs are covered by car sales. (These chargers only work on Teslas, and electricity costs are low enough that they can afford to provide lifetime charging for their customers.) Some chargers are paid, and that's typically done with an RFID card (either a regular credit card with RFID, or a card specifically for the charging network) or a smartphone app.
My random guess is that we'll go to plain old mileage reporting. Fuel taxes for road maintenance may have made sense a long time ago, but fuel use and road wear are fairly weakly correlated now even among gasoline cars, since efficiency can vary so much now.
A possible alternative would be to tax the electricity at the charger, but that also opens up more cans of worms.
Another thing to consider is that, beyond normal weathering, most road damage comes from heavy (and often overweight) trucks.
I don't see taxing electricity at the charger as being viable, because it's too decentralized. You can tax gasoline because it's distributed by relatively few places. You can charge a car off a normal 240V outlet (or 120V if you don't mind it being slow) so it'll be way too easy to dodge.
Tracking mileage and assigning to the state of registration might not be too bad. It won't be fully accurate, but the inaccuracies will balance out to an extent. Gas already suffers from this at a smaller level, since you can buy gas in one state and then drive a substantial distance in another state.
The fact that trucks are the ones doing all the damage is a big wrench in the works. Maybe the proper solution would be paying some by taxing truck mileage and making up the rest out of general taxes.
Combined with the relentless expansion of solar and wind in the US, I disagree with your assertion that energy prices will rise long-term. You'll probably see peaks and troughs as demand increases and supply comes online, but there is a lot of land left for renewables to be deployed to.