South Dakota home charging cost for the 2027 Rivian R1S Quad (20in AT)

In South Dakota, home electricity runs 14.33¢/kWh — put a 2027 Rivian R1S Quad (20in AT)'s EPA-rated 50.1 kWh/100mi against that and 100 miles costs $7.18, versus $16.02 for a gas car averaging 25.5 mpg. Charging at home is much cheaper than gas here: 55.2% less than gas per mile, here specifically.

What a year of driving costs

At fueleconomy.gov's default of 15,000 annual miles, the 2027 Rivian R1S Quad (20in AT) costs roughly $1,077 a year to charge at home in South Dakota, against roughly $2,403 a year for an equivalent gas car. That's a savings of about $1,326 a year.

What one full charge costs

Covering the 2027 Rivian R1S Quad (20in AT)'s EPA-rated 325-mile range takes about 162.8 kWh, which costs about $23.33 at South Dakota's residential rate — figured from the EPA's own combined range and consumption numbers, not the pack's nameplate capacity.

How this compares nationally

This combination ranks 13,501 of 20,400 state/model pairs for cost savings against gas (1 is cheapest). The Rivian R1S Quad (20in AT) alone ranks 390 of 400 models for efficiency; South Dakota alone ranks 14 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 South Dakota electrician quotes for Level 2 install before you commit either way.

Where these figures come from

Every figure on this page traces to a named EIA or EPA dataset — see the methodology guide. At 14.33¢/kWh, South Dakota sits in the middle of the national range — the guide to why charging cost varies by state shows where.