NorthWestern Energy and solar
NorthWestern Energy is an investor-owned utility serving about 51,787 homes in South Dakota. Here's what its rates and export rules mean for solar: for a typical customer, solar is not worth it.
- Average price (2026 est.)
- 14.2¢0% above South Dakota average
- Typical bill
- $134939 kWh a month
- Exports credited
- ~28%Avoided-cost export credit
- Typical payback
- 21.5 yrs4 kW, cash
Export rules for NorthWestern Energy customers
Avoided-cost export credit, varies netting.
Avoided-cost buyback; verify current tariff.
Solar for a typical NorthWestern Energy home
| System | 4 kW (50% of 939 kWh/month) |
|---|---|
| Cost | $13,500 |
| First-year savings | $651 |
| Payback | 21.5 years |
| 25-year net | $2,538 |
Uses the utility's average price.
Solar adoption
- Homes with solar (2025)
- —
- Share of customers
- —
- Residential solar capacity
- —
- Residential customers
- 51,787
EIA-861, 2025.
Questions about NorthWestern Energy and solar
Does NorthWestern Energy have net metering?
Avoided-cost buyback; verify current tariff.
How much does electricity cost with NorthWestern Energy?
Residential customers paid an average of 13.4¢ per kWh in 2025 (EIA), about 14.2¢ adjusted to 2026. The typical home uses 939 kWh a month, a bill of about $134.
Is solar worth it with NorthWestern Energy?
For a typical customer, solar is not worth it: a 4 kW system costing about $13,500 pays back in about 21.5 years, with $2,538 net over 25 years.
How many NorthWestern Energy customers have solar?
NorthWestern Energy did not report residential net-metered solar to EIA for 2025.
Legal name: NorthWestern Energy - (SD) (EIA ID 13809). Data: EIA-861 2025 and monthly data through 2026, state policy research October 2026.