Idaho home charging cost for the 2026 Rivian R1S Tri Max (22in)

At Idaho's residential electricity rate of 12.8¢/kWh, a 2026 Rivian R1S Tri Max (22in) (rated 44.6 kWh per 100 miles by the EPA) costs $5.71 to drive 100 miles on home charging, against $16.02 for the same distance in a car averaging 25.5 mpg on gasoline at $4.085/gallon. Charging at home is much cheaper than gas here: 64.4% less than gas per mile, here specifically.

What a year of driving costs

At fueleconomy.gov's default of 15,000 annual miles, the 2026 Rivian R1S Tri Max (22in) costs roughly $856 a year to charge at home in Idaho, against roughly $2,403 a year for an equivalent gas car. That's a savings of about $1,547 a year.

Cost of a full charge

Covering the 2026 Rivian R1S Tri Max (22in)'s EPA-rated 371-mile range takes about 165.4 kWh, which costs about $21.17 at Idaho's residential rate — figured from the EPA's own combined range and consumption numbers, not the pack's nameplate capacity.

2026 Rivian R1S Tri Max (22in) in Idaho, ranked

This combination ranks 7,987 of 20,400 state/model pairs for cost savings against gas (1 is cheapest). The Rivian R1S Tri Max (22in) alone ranks 356 of 400 models for efficiency; Idaho alone ranks 3 of 51 states for electricity price.

Next step: home charger installation

The numbers above assume Level 2 home charging is already in place — the electrical work behind that is a real, separate cost that varies by panel, wiring, and local labor rates, not something this page's per-mile math includes.

Line up a few Idaho electrician quotes for Level 2 install before you commit either way.

Where these figures come from

See the methodology guide for exactly which EIA and EPA figures feed 2026 Rivian R1S Tri Max (22in)'s cost in Idaho. Idaho is one of the cheapest states for home electricity — the guide to why the cost varies so much by state covers what drives that.