“Does that even work where it gets to minus twenty?” It is probably the question we hear most. The short answer is yes, with caveats that are worth understanding before you sign anything.
Cold is not the problem
Solar panels like cold. Electronics are more efficient at lower temperatures, and panel voltage rises as the mercury falls, so a crisp, clear January day can produce more per hour of sunshine than a scorching July afternoon. The issue in winter is not frost. It is the amount of light that reaches the glass.
What actually shrinks in winter
Four things work against you from November to February. Days are short, so there are fewer hours of sun. The sun sits low, so light arrives at a flatter angle and passes through more atmosphere. Overcast stretches are common in many regions. And snow cover on the panels stops production until it clears.
Taken together, a December month can produce only a small fraction of a June month. That is normal. It is also already built into the yearly estimates a good installer gives you. A kilowatt of solar in southern Canada often yields roughly 1,100 to 1,400 kWh a year, depending on location and design, and the Prairies and southern Alberta and Saskatchewan are among the sunniest places in the country. Winter simply takes a smaller share of that total.
A rough picture of the year
| Season | What to expect |
|---|---|
| December and January | Lowest output of the year, snow and cloud common |
| February and March | Rapid recovery as days lengthen, bright cold days can be very productive |
| April to August | The bulk of annual production, often more than the house uses |
| September to November | Declining steadily, still useful |
For a detailed month-by-month look, see how solar output changes through the year.
Snow, handled calmly
Panels are slippery glass set at a tilt, and they warm up as soon as any light gets through. Most snow slides off within a day or two. Leave it alone unless you can reach it safely from the ground with a soft tool made for the job. Never use sharp or metal tools, never scrape, and do not go up on an icy roof. Annual snow loss is usually a modest share of yearly output, so waiting is rarely costly.
A steeper tilt sheds snow faster. Some homeowners accept a bit of extra snow loss in exchange for a sturdier, lower-cost mount, and snow on the ground nearby can reflect extra light onto the panels on bright days. Ask your installer what they assume. Our guide to snow on solar panels covers the practical side in more depth.
Solar hot water in the cold
This is where design counts. A closed loop filled with a water and glycol mix will not freeze, and a well-built system keeps working through winter, though it delivers less. Evacuated-tube collectors do especially well in cold, windy weather because their vacuum insulation keeps heat from escaping. Flat plate collectors are cheaper and shed snow readily because they leak a little heat.
Whichever type you consider, confirm in writing how the system is protected from freezing and what happens if the pump stops. If you want the basics first, read how solar hot water works.
A worked example
Picture a 7 kW system on a two-storey house in southern Ontario. At roughly 1,100 to 1,400 kWh per kW, that is around 7,700 to 9,800 kWh a year, which would cover most of a typical household’s 9,000 to 12,000 kWh. In June it may overproduce. In December it may cover only a modest slice of that month’s use, and a house with electric heating will be buying plenty from the grid. Over twelve months the picture can still look good, as long as your utility banks the summer surplus.
Why annual numbers still add up
Most provinces credit exports at or near retail rate, often with credits that roll over for about a year, so the summer surplus helps cover darker months. Rules differ: Alberta and Manitoba use arrangements with lower export credits, and BC reportedly changed its rate structure in mid-2026. Read how net metering works across Canada and then confirm the current terms with your utility, since they change.
Practical tips for a cold-climate roof
- Keep trees trimmed, since low winter sun makes shadows longer
- Choose mounting hardware rated for your region’s snow and wind loads
- Check that wiring and connectors are rated for low temperatures
- Keep the lower edge of the array clear of places where snow can pile up against it
- Look at your monitoring app after storms so you notice a problem early
Seasonal upkeep is simple, and our maintenance checklist puts it in one place.
What to ask your installer
Ask for a month-by-month production estimate rather than one annual figure, and ask which tilt and snow-loss assumptions sit behind it. Ask what the racking is rated for in snow and wind, how wiring is protected from ice and ice dams, and whether the monitoring will alert you to a dead string. A clear answer on each is a good sign, and vague answers are worth a second quote.
A fair expectation
Do not expect solar to run your whole house in December. Expect it to take a real bite out of the year. If a salesperson promises otherwise, ask them to show the month-by-month numbers behind the claim. The cold climate hub collects our winter and weather guides.
Quick answers
Do solar panels work in Canadian winters?
Yes. Output is lower because of short days, low sun and snow cover, but cold temperatures actually help panel efficiency.
Should I remove snow from my solar panels?
Usually no. Tilted panels shed snow on their own, and scraping can damage them. Never climb onto an icy roof.