It’s a common myth that solar panels don’t work well in the winter. In fact, solar panels operate more efficiently in the cold. As solar panels get hotter, they produce less power from the same amount of sunlight. The white of the snow also reflects light and can help with performance.
Of course, the further north you go the shorter the days are in the winter. This means that depending on where you are located your solar array could produce between 10% to 25% less energy. However, this difference will be made up in the summer when the days longer than at the equator. Fortunately, Calgary is among the places in Canada that experiences the most sunshine. This means that despite a loss of energy production in the winter, Calgarians get to maximize their output.
What About the Snow?
Solar panels that are covered in snow will not produce energy. However, sunlight will penetrate snow up to a few inches and will warm the panel and help melt the snow. Also, since northern solar arrays need to be pitched to optimally produce, the angle well help the snow slide off. The ideal fixed pitch in Calgary is 51°.
The Northern Alberta Institute of Technology (NAIT) conducted a study to determine the impact of snowfall on solar panels. It showed that at a 53° pitch (ideal fixed pitch for Edmonton) the performance was only impacted by 3.02% during winter months and overall by 1.65% over the first 3 years of the study. This means the impact of snowfall on solar panels is minimal.