Black Hills Power, Inc.
Investor Owned electric utility · South Dakota · #248 of 3,199 U.S. utilities by customers · EIA utility #19545
Black Hills Power, Inc. is a investor owned electric utility serving 85,804 customers in Montana, South Dakota, Wyoming. In 2025 it sold 1,858 gigawatt-hours of electricity for $243.47M in revenue, an average realized rate of 13.10¢ per kWh across all customer classes and 15.07¢ per kWh for residential customers. Its reported service territory covers 11 counties. EIA records its activities as: generation, transmission, buying transmission, distribution, wholesale marketing.
Customers, sales and rates by customer class (2025)
| Class | Customers | Sales (GWh) | Revenue | Avg realized rate | Share of sales |
|---|---|---|---|---|---|
| Residential | 69,800 | 588 | $88.67M | 15.07¢ | |
| Commercial | 15,980 | 829 | $115.41M | 13.93¢ | |
| Industrial | 24 | 441 | $39.40M | 8.93¢ | |
| Total | 85,804 | 1,858 | $243.47M | 13.10¢ |
Average realized rate = revenue divided by sales as reported on EIA Form 861. It blends fixed charges, demand charges and riders into one per-kWh figure; it is not the utility's tariff rate. Estimated residential bill assumes the average residential customer's actual 2025 usage (702 kWh/month).
Operations by state
| State | Customers | Sales (GWh) | Residential rate |
|---|---|---|---|
| South Dakota | 82,900 | 1,527 | 15.12¢ |
| Wyoming | 2,857 | 171 | 13.77¢ |
| Montana | 47 | 160 | 6.99¢ |
Five-year trend
| Year | Customers | Sales (GWh) | Revenue | Residential rate |
|---|---|---|---|---|
| 2021 | 74,147 | 1,829 | $235.78M | 15.10¢ |
| 2022 | 75,131 | 1,875 | $226.11M | 13.87¢ |
| 2023 | 76,031 | 1,840 | $214.44M | 13.63¢ |
| 2024 | 77,522 | 1,870 | $230.09M | 14.33¢ |
| 2025 | 85,804 | 1,858 | $243.47M | 15.07¢ |
Reliability (2025)
Average outage time (SAIDI): 541 minutes per customer per year
Average outages (SAIFI): 2.27 per customer
Average restoration time (CAIDI): 239 minutes
As reported for South Dakota under the IEEE standard, with major event days included where the standard reports them. Lower is better; see the reliability rankings.
Energy supply (2025)
Net generation: 1,625 GWh
Wholesale power purchased: 1,257 GWh
Winter peak demand: 343 MW
Energy losses: 13.1% of energy handled
Meters & rooftop solar (2025)
Smart (AMI) meters: 100.0% of 85,804 meters
Customer-sited generation (net metering): 264 installations, 2.5 MW of capacity
Counties served
Butte, SDCampbell, WYCarter, MTCrook, WYCuster, SDFall River, SDLawrence, SDMeade, SDPennington, SDPowder River, MTWeston, WY
Other large utilities in South Dakota
- NorthWestern Energy - (SD) - 65,396 customers, residential 13.35¢
- Sioux Valley SW Elec Coop - 30,059 customers, residential 13.87¢
- Southeastern Electric Coop Inc - (SD) - 24,428 customers, residential 12.98¢
- West River Electric Assn Inc - 21,332 customers, residential 15.16¢
- Watertown Municipal Utilities - 14,497 customers, residential 9.29¢
- City of Brookings - (SD) - 12,568 customers, residential 10.69¢
- Black Hills Electric Coop, Inc - 11,478 customers, residential 14.79¢
- Butte Electric Coop, Inc - 7,472 customers, residential —
All South Dakota utilities and rates
Source: U.S. Energy Information Administration, Form EIA-861 2025 (filed by the utility; figures as published). Utility #19545 in the EIA frame.