In short: Lewiston has about 34,700 people and sits in Nez Perce County. Avista Corp serves the county, averaging 11.62¢ per kWh for homes in 2024 (EIA). Rooftop solar here makes roughly 1,170 kWh a year per kW of panels by our estimate, which is about average for the U.S..
This page covers what is local to Lewiston: its utility, outage records, sunshine, weather risks and charging. Statewide rules such as net metering, incentives and electrician licensing are in our Idaho energy guide.
Lewiston at a glance
- Place: Lewiston, Nez Perce County, Idaho; about 34,693 residents (Census Bureau estimate, July 2024).
- Utility: Avista Corp (investor-owned). Homes paid an average 11.62¢ per kWh in 2024 (EIA-861); the average customer lost 165 minutes of power on normal days and 225 counting major storms, with 1.1 interruptions a year (utility-wide, not just Lewiston).
- Sun: 4.00 kWh per square meter per day on average, from 1.01 in December to 7.52 in July (NASA POWER). Our rough estimate: about 1,170 kWh a year per kW of panels.
- Climate: about 580 cooling degree-days and 6,230 heating degree-days a year (base 65°F, NASA POWER), so heating is the big load.
- Top hazards in Nez Perce County: wildfires “relatively moderate”, river and heavy-rain flooding “relatively low” and heat waves “relatively low” (FEMA National Risk Index; overall county risk rated “very low”).
- Public charging: 21 ports at 5 locations in Lewiston, 16 of them DC fast (AFDC, October 20, 2026).
Your utility and what it means
Avista Corp is an investor-owned utility and served about 128,226 home customers in 2024; its 11.62¢ average was below the 13.73¢ statewide average for July 2026. Those are utility-wide averages, not a quote for your address; your own bill is the real number.
For reliability, Avista Corp reported 165 minutes per customer without major storms in 2024, less than the statewide figure of 174 (EIA-861). Utility-wide numbers hide a lot: a home at the end of a long rural line usually has more outages than the average.
Net metering, export rates and incentives are set at state level and by each utility. Start with the Idaho guide and then ask your utility for its current interconnection steps before you sign anything.
Backup power in Lewiston
- Wildfires (relatively moderate): Wildfire risk can mean planned shutoffs and smoke. A battery charged by solar gives quiet backup, and fueled generators need extra care on dry days and clear space around them.
- River and heavy-rain flooding (relatively low): Heavy rain can flood basements and take out power. Put sump pumps on backup power and keep equipment above the flood line.
- Heating load: a winter outage can stop a furnace blower, boiler pump or heat pump. List what your heat needs to run before choosing a generator or battery.
- Short outages: a portable power station covers phones, Wi-Fi, a CPAP and lights; a home battery switches over automatically.
Size your setup with the generator sizing tool and the battery backup calculator, and compare options in backup power. Generator safety (CPSC): outdoors only, at least 20 feet from the house, exhaust away from doors and windows, never in a garage, and battery-powered carbon monoxide alarms inside. A licensed electrician should install any transfer switch, with a permit; see generator installation.
Solar in Lewiston
By our rough estimate each kW of panels makes about 1,170 kWh a year in Lewiston (NASA sunshine data times 365 days times 0.80 for system losses). Valued at Avista Corp’s 2024 average of 11.62¢, that is about $136 a year per kW if all of it offsets your own use (an estimate, not a promise). Production swings with the seasons: July is the sunniest month at 7.52 and December the dimmest at 1.01, a 7.5-to-1 gap, so a battery or a bigger system helps in winter.
Check your own roof with the solar potential tool, see solar costs and net metering vs net billing, and read the steps in solar installation.
Batteries and EV charging
A home battery earns its place when outages are frequent, when your utility pays little for exported solar, or when evening prices are high; compare in home batteries and battery costs. Lewiston has 21 public charging ports in the federal station list including 16 DC fast, but home charging is cheaper and easier: see the EV charging cost calculator and EV charger installation.
Drive on another fuel? See every alternative fuel station in Lewiston: hydrogen, propane, natural gas, E85 ethanol, biodiesel and renewable diesel.
Permits and inspections
Solar, generator transfer switches and EV chargers normally need an electrical permit from the Lewiston building or permitting department, or from Nez Perce County if you live outside city limits, and often a utility interconnection approval. We have not verified a local permit page for Lewiston, so check the city and county websites or ask your electrician, who will know the process. Hire only a licensed electrician or installer; the Idaho guide lists the state licensing rules.
Nearby guides
More local guides: see all of Idaho, or the whole Idaho energy guide.
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Lewiston energy FAQ
Who is my electric company in Lewiston?
Federal data lists Avista Corp as the main utility serving Nez Perce County. Small areas can be served by a different company or a co-op, so confirm on your bill.
How much power will solar make in Lewiston?
About 1,170 kWh a year per kW of panels by our estimate, so a 6 kW system would make roughly 7,020 kWh. Shade, roof direction and tilt change this; run your address through the solar potential tool for a better number.
Will a home battery keep my heat on in an outage?
It can keep a furnace blower, boiler pump or a heat pump running for a while, but long cold outages drain a battery fast without solar to recharge it. Pair it with a generator or wood or propane heat if outages here run for days.
Do I need a permit for solar or a generator in Lewiston?
Almost always an electrical permit for a transfer switch, solar or an EV charger, issued by the city or county where you live. Your licensed electrician or installer normally pulls it. Never connect a generator to your house wiring without a transfer switch.
Sources: EIA Form 861 (2024) for utility prices and outages; NASA POWER climatology (2001 to 2025) for sun and degree-days; FEMA National Risk Index for county hazards; AFDC station locator for public charging; Census Bureau for population. Estimates are ours and are not promises; see our editorial policy. Prices and programs change, so check each program page.