Charging a 2027 Rivian R1S Quad (22in UHP) at home in Hawaii

In Hawaii, home electricity runs 45.95¢/kWh — put a 2027 Rivian R1S Quad (22in UHP)'s EPA-rated 47.3 kWh/100mi against that and 100 miles costs $21.76, versus $16.02 for a gas car averaging 25.5 mpg. Here the math runs the other way: 35.8% more per mile than gasoline, because Hawaii's rate and this model's efficiency combine unfavorably.

What a year of driving costs

Hawaii owners putting 15,000 annual miles on a 2027 Rivian R1S Quad (22in UHP) spend about $3,263 on home electricity, compared to about $2,403 a gas-car equivalent would spend on fuel. At this mileage, that's roughly $860 a year worse than the gas comparison.

What one full charge costs

At Hawaii's rate, fully covering this 2027 Rivian R1S Quad (22in UHP)'s 338-mile EPA range costs about $73.53 (160 kWh) — the energy the EPA test actually used, not the battery's rated size.

Where this ranks

Among all 20,400 state-and-model combinations this site tracks, charging a 2027 Rivian R1S Quad (22in UHP) in Hawaii ranks 20,364 for cost savings versus gas — 1 being the best deal nationally. Separately, the Rivian R1S Quad (22in UHP) ranks 371 of 400 EV models for raw efficiency, and Hawaii ranks 51 of 51 for cheapest residential electricity.

Before you install a home charger in Hawaii

Everything above is the per-mile and per-year cost once a home charger exists — getting one installed is a separate electrical job whose price depends on your panel and wiring, not the state average used here.

Ask a licensed Hawaii electrician to quote the install before this math becomes a real decision.

More on how this number was built

The methodology guide names the exact EIA and EPA tables behind this page's numbers. This is one of the combinations where charging costs more than gas — the guide to when that happens explains why the arithmetic can go either way.