Let's say you can go 200 miles with that $8 of energy, that's 4 cents a mile.
Let's say a gas car is 30 miles per gallon of $3 gas, or 10 cents a mile. Over 200,000 miles, that's $20,000 for fuel, versus $8,000 of electricity in the EV. Seems like the total cost of ownership just about breaks even with federal rebates, and ignoring maintenance costs (generally expected to be higher with the gas vehicle) and ignoring that paying the cost up-front for an EV removes the potential for that money to accrue interest (which favors the gas vehicle).
I'm hoping the EV costs continue to fall until we get to close to parity in terms of vehicle purchase price. This can happen either by battery prices falling, or for people to adjust their expectations and accept shorter range, or for the need for large batteries to become obsolete due to electrified roads that let you charge while the vehicle is still moving.
You're saying that gas is $3/gallon and electricity is $12/kWh?
Over here gas is around $7,50-$8 per gallon and electricity is around $0.05/kWh. A 100km drive in an EV costs around 2€, while in a petrol powered car the cost is 8.5€ for a low consumption car.
No wonder Americans drive huge cars with no regard to consumption :D
Even in CA, with some of the most expensive electricity, it's about $0.20 - $0.25 / kWh...
Repairs can take months due to lack of spare parts.
Plus fun fact: My insurance would go up a lot with a Model 3 from my current vehicle, 25% more a month. Why? I have no idea, but I'm guessing higher write-off or repair costs.