Do solar panels work in the winter in Oregon?

Yes. Output is lower because days are shorter and the sun is lower: December production is about 22% to 38% of July across Oregon cities. Net metering credits from summer cover much of the gap.

Do solar panels work better in cold weather?

Yes. Panels are more efficient when they're cold. A cold, clear day produces more power per hour of sun than a hot summer afternoon, but winter has far fewer hours of strong sun.

Do solar panels work with snow on them?

A thin layer lets some light through; heavy snow stops production until it slides or melts off, which usually takes a day or two of sun on tilted panels.

Should I clear snow off my solar panels?

Usually no. It's not worth the risk of a fall or scratched glass. The snow will clear on its own, and a few days of lost winter production is a small part of the year's total.

Do solar panels work during a winter power outage?

Only with a battery. Grid-tied systems shut off during outages for lineworker safety. A battery lets solar keep powering essentials and recharge each day.

Clear rooftop solar panels catching winter sunrise above snow-covered Central Oregon pasture with Cascade peaks behind.

Solar in winter

Do solar panels work in winter, snow and cold?

How cold, snow, clouds and short days affect solar in Oregon, with month-by-month production data for cities across the state.

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Updated November 4, 2026

The short answer

Yes. Cold actually helps: solar panels are more efficient at low temperatures. What limits winter output in Oregon is short days, a low sun angle and snow cover. A kW of panels in Portland makes about 36 kWh in December versus 160 in July, and in Bend about 63 versus 177 (NREL). Snow usually slides off tilted, dark panels within a day or two of sun, and net metering carries summer surplus forward to cover winter bills.

Updated November 4, 2026

Cold weather: Makes panels more efficient
What actually limits winter: Short days and low sun
Portland, December: 36 kWh per kW (July: 160)
Bend, December: 63 kWh per kW (July: 177)
Snow: Usually slides off within a day or two of sun
Winter bills: Net metering banks summer credit

By city

How much solar makes in an Oregon winter

Modeled solar production per installed kW, December vs. July
City	December (kWh per kW)	July (kWh per kW)	December as % of July	Dec to Feb share of the year
Portland	36	160	23%	11%
Salem	37	166	22%	12%
Eugene	36	156	23%	12%
Astoria	32	139	23%	13%
Bend	63	177	36%	15%
Medford	50	169	30%	14%
Klamath Falls	69	183	38%	16%

Portland
December (kWh per kW)
36
July (kWh per kW)
160
December as % of July
23%
Dec to Feb share of the year
11%
Salem
December (kWh per kW)
37
July (kWh per kW)
166
December as % of July
22%
Dec to Feb share of the year
12%
Eugene
December (kWh per kW)
36
July (kWh per kW)
156
December as % of July
23%
Dec to Feb share of the year
12%
Astoria
December (kWh per kW)
32
July (kWh per kW)
139
December as % of July
23%
Dec to Feb share of the year
13%
Bend
December (kWh per kW)
63
July (kWh per kW)
177
December as % of July
36%
Dec to Feb share of the year
15%
Medford
December (kWh per kW)
50
July (kWh per kW)
169
December as % of July
30%
Dec to Feb share of the year
14%
Klamath Falls
December (kWh per kW)
69
July (kWh per kW)
183
December as % of July
38%
Dec to Feb share of the year
16%

NREL PVWatts, south-facing 20° tilt, 14% system losses, at each city's coordinates. Your roof's direction and shading change the numbers.

See your city's month-by-month numbers

Cold

Why cold isn't the problem

Solar panels convert light, not heat, into electricity, and they lose efficiency as they get hot. A typical panel gains a few tenths of a percent of output for every degree Celsius it runs below 25°C (77°F), so a clear, cold January day is efficient solar weather.

The real winter limits are the number of daylight hours and how low the sun sits in the sky. That's why Central and Southern Oregon, with clearer winter skies, keep a larger share of their summer output than the Willamette Valley and the coast.

Snow

Solar panels and snow

Panels are tilted, smooth and dark, so snow usually slides off within a day or two once the sun comes out. Light snow often melts off first.
Don't climb on the roof or use metal tools, hot water or a pressure washer to clear panels. Scratched glass or a fall costs far more than a few days of lost production.
Snow on the ground can actually boost output on clear days by reflecting extra light onto the panels.
In snowy areas such as Bend, Sisters and La Pine, we design racking for local snow loads, and the permit inspection confirms it.

Clouds

Clouds, rain and fog

Panels still produce under clouds, just less: heavy overcast can cut output to a small fraction of a sunny day, while thin clouds have a much smaller effect. Rain also rinses dust and pollen off the glass.

Do solar panels work on cloudy days?

Winter bills

How net metering covers winter

Oregon systems are usually sized on a full year of usage, not on winter. In spring and summer they make more than the home uses, and PGE and Pacific Power credit that surplus on your bill. Those credits carry forward to winter months, when production is low and electric heating pushes usage up.

Winter outages

Solar during ice storms and winter outages

Grid-tied solar shuts off during a power outage unless the home has a battery. With a battery, solar keeps recharging it every day, though short winter days mean less recharging, so we size winter backup around essentials such as the furnace fan, fridge, lights and well pump.