It really depends on your state, our payback was 3 years, but best you can get now is 6 years due to incentives changed.

$34000 cost

One time: -$10200 federal tax credit (was 30% when we got it) -$1000 state rebate

Per year for 10 years: -$3000 state incentives (no longer offered by our state)

Per year until EOL (25 years): -$3500 power usage offset (EV uses lots of power + high power costs .25c/kwh)

State incentive no property tax increase for 20 years.

Total net difference over 25 years:

$98100

Equivalent APR: ~11%

Note that my case was a very much ideal case, but it did only about the same as the bullish market we've been having over the last decade.