Cheapest petrol near my house is currently $8.45 / us gallon. The pain of living in Europe.
Diesel is slightly lower, at $6.50. (Lower tax to help the trucking industry.)
I drive a diesel, but no matter how fast or slow I drive, I always get around 45 mpg. I suspect a mechanical issue.
In total, I get about $0.15/mile in fuel cost alone, something like $0.32/mile including our "road tax" and mandatory 3nd party insurance.
An electric car only makes sense if you get lucky buying batteries. I did a calculation a while back, using then commercially availible cheap batteries, and I came to about $.20 to $0.30/mile in battery depreciation alone (assuming 100wh/mile, 1500 charge cycles, cheap RC lipoly or LiFePO4 packs, etc..) Total cost of ownership: cheaper to run a gas guzzler than an EV, even with our ridiculous fuel prices in Europe.
I re-did the calculation for recycled 18650 batteries, looks much better now, depending on how cheaply you can obtain "dead" or used laptop batteries.
Even new batteries came down in price quite a bit compared to 5 years ago.
But hardly enough to justify them, other than feeling good about driving an EV.