Do Solar Panels Work in Winter?

As winter blankets regions like Canada, it's natural to question the effectiveness of solar panels in such harsh conditions. Many believe solar panels might struggle or underperform during the colder months, but this is a misconception. Solar panels can effectively meet energy needs even during the Canadian winter.

The Cold Advantage

Solar panels exhibit increased efficiency in colder weather. Colder temperatures improve energy production efficiency, increasing the daily amount of electricity produced despite fewer daylight hours. Solar panels function optimally on bright, cold days because they rely on sunlight, not heat, to generate electricity. The conductivity of the materials used in solar panels tends to improve in the cold, enhancing electricity production. Solar panel efficiency is less affected by extreme cold than extreme heat.

Snow and Sunlight

But what about snow? Surely that disrupts how much energy is generated, right? This is true, especially in heavy snowfall regions of Canada, however, sunlight can still reach solar panels and maintain energy production even with light snow cover. Yes, production will be hampered compared to solar panels free of snow, but it isn’t entirely a write-off.

A study conducted by the Northern Alberta Institute of Technology (NAIT) which found snow coverage only results in roughly 5% annual energy loss due to snow coverage (compared to snow-cleared arrays) across their five year study. The project is still ongoing and results are posted live here. Results however will vary from property to property, but does show some compelling results for winter production.

Snow reflection can boost the efficiency of bifacial modules, especially on ground mounted or flat roof arrays through the Albedo Effect. The dark surface of solar cells attracts heat, causing snow to thaw and slide off, leaving a clean and effective panel surface. Solar panels are engineered to withstand heavy snow and wind loads.

Ground mounted solar array in winter.

Reduced daylight hours and lower sun angles do affect solar panel output, but modern solar technology can harness available light, even on overcast days. Since 2010, solar panels have gained twice as much efficiency as solar panels of the last decade. Most solar panels installed in Ontario during the start of the Micro-FIT Program (2010) were 180 – 225W modules. Today in the same footprint, solar modules can reach 500W.

Some homes even have roof angles that with a little thaw can cause snow to completely slide off the modules and “self-clean”. It is recommended that during heavy snowfall, some clearing will be required should you want to produce in the winter, however, we recommend that contacting a solar professional to clear the snow would be safer.

Incentives and Savings

Both provincial and federal governments provide grants, loans, and/or rebates for energy-efficient home upgrades, including solar panels. Solar panel systems are connected to the grid, and excess electricity generated during sunnier months can offset winter energy consumption. 

---

To find out how you could benefit from going solar, contact one of our Solar Specialists below to learn more.

Free Solar Assessment