Power plants in the Avista balancing area

The Avista balancing area takes in 30 power plants with 2,309 MW of nameplate capacity, the 38th-largest of the 40 areas covered here. Its plants sit in three states, with Idaho holding 38% of the capacity. Hydroelectric makes up 51% of the mix, and the largest plant is Noxon Rapids (488 MW). Since 2020, 244 MW has come online here, 100% of it wind.

Hydroelectric1,174 MW51%
Natural gas564 MW24%
Wind349 MW15%
Biomass and waste200 MW8.7%
Solar19.2 MW0.8%
Oil and petroleum2.8 MW0.1%

Capacity by decade it came online

Natural gasOil and petroleumHydroelectricWindSolarBiomass and waste

Above the line: capacity operating in 2025. Below: capacity retired at plants that still run.

The 25 largest plants in the area

Rank	Plant	State	Runs on	Capacity	First unit
1	Noxon Rapids	Montana	Hydroelectric	488 MW	1959
2	Rathdrum Power LLC	Idaho	Natural gas	302 MW	2001
3	Cabinet Gorge	Idaho	Hydroelectric	265 MW	1952
4	Rathdrum	Idaho	Natural gas	166 MW	1994
5	Rattlesnake Flat	Washington	Wind	144 MW	2020
6	Clearwater Paper IPP Lewiston	Idaho	Biomass and waste	114 MW	1950
7	Palouse	Washington	Wind	105 MW	2012
8	Clearwater Wind III	Montana	Wind	100 MW	2024
9	Summer Falls Power Plant	Washington	Hydroelectric	92 MW	1985
10	Box Canyon	Washington	Hydroelectric	90 MW	1955
11	Long Lake	Washington	Hydroelectric	70 MW	1915
12	Northeast (WA)	Washington	Natural gas	61.8 MW	1978
13	Kettle Falls Generating Station	Washington	Biomass and waste	57.9 MW	1983
14	Little Falls (WA)	Washington	Hydroelectric	43.2 MW	1910
15	Nine Mile	Washington	Hydroelectric	37.6 MW	1908
16	Main Canal Headworks	Washington	Hydroelectric	26.8 MW	1987
17	Spokane Waste to Energy	Washington	Biomass and waste	26 MW	1991
18	Boulder Park	Washington	Natural gas	24.6 MW	2002
19	Adams Nielson Solar	Washington	Solar	19.2 MW	2018
20	Upriver Dam Hydro Plant	Washington	Hydroelectric	17.6 MW	1936
21	Monroe Street	Washington	Hydroelectric	14.8 MW	1992
22	Post Falls	Idaho	Hydroelectric	14.5 MW	1906
23	Upper Falls	Washington	Hydroelectric	10 MW	1922
24	Plummer Cogen	Idaho	Biomass and waste	6.2 MW	1982
25	Grimes Way	Washington	Natural gas	4 MW	2005

States

State	Plants	Capacity
Idaho	8	872 MW
Washington	20	849 MW
Montana	2	588 MW

Operators with the most capacity

Operator	Plants	Capacity
Avista Corp	12	1,254 MW
Rathdrum Power LLC	1	302 MW
Rattlesnake Flat, LLC	1	144 MW
Columbia Basin Hydropower	2	119 MW
Clearwater Paper Corporation	1	114 MW
Onward Energy	1	105 MW
Clearwater Wind III, LLC	1	100 MW
PUD No 1 of Pend Oreille County (WA)	1	90 MW
City of Spokane (WA)	2	43.6 MW
Strata Manager, LLC	1	19.2 MW