$42.77full charge
The i4 eDrive40 (81 kWh) costs about $42.77 to charge fully at Hawaii's average home rate of 48.00¢/kWh, including ~10% charging loss (89.1 kWh from the wall). That is $12.84 per 100 miles.
EIA residential average, Hawaii, 2026-07 (latest in this book). No Hawaii gasoline series, so this uses PADD 5 regular, week of Oct 5, 2026.
No bordering states.
At 1,000 miles a month and 30 mpg, home charging costs $128.43 and the gas car costs $190.90. The EV saves $62.47 a month at $5.727/gal. Both miles and mpg are editable on the calculator.
The listed DC fast-charge time to 80% is 31 minutes at up to 205 kW. A full home charge is a different session. This page prices the energy from the wall, not how long a Level 2 charger takes.
This page uses the residential rate. Public fast-charging prices are a separate scenario and are not included.