Tool

What does a mile actually cost?

Grid power, generator power, and gasoline, side by side. Generator charging is expensive — the point is knowing by how much.

Electricity rate ($ per kWh) Gasoline price ($ per gallon) Generator output (kWh per gallon) EV efficiency (mi/kWh) Gas car for comparison (mpg)

Grid charging–

Generator–

Gasoline car–

Per milecost basis

Reading this honestly

Generator charging is almost always the most expensive mile on the board, and anyone telling you otherwise is selling something. A gallon of gasoline holds roughly 33 kWh of energy; a portable generator converts perhaps 5–8 kWh of that into usable electricity. You are paying for the other 25 kWh as heat and noise.

That doesn't make it pointless. It makes it insurance. The comparison that matters isn't generator versus grid — it's generator versus not going anywhere.

What the numbers assume

10% loss between the outlet and the battery, which is typical for AC charging
Generator output per gallon varies with load; lightly loaded generators are far worse than the figures here
Gasoline comparison ignores maintenance, which favours the gas car more than reality does

Charge rate calculator → · Why winter changes all of this →

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