Many homeowners suspect that solar panels will get covered with snow, and efficiency will drop. This common myth is not actually the reality for most solar panels. Solar panels are designed to be versatile and withstand a myriad of weather conditions – including winter weather. While it’s true that a thick layer of snow would prevent the photovoltaic cells in a solar panel from generating electricity, a typical dusting or a few inches won’t pack on enough to completely block all sunlight. Plus, the reflective nature of snow might increase the amount of light that hits your panels and boost production.
The snow will also likely slide right off your panels. This is because in heavy snowfall areas, like Alberta, installing solar panels to receive the most sunlight at the “correct” angle is actually incentivized when heavy wet snowfalls hit and are immediately melted off by the next day’s warm temperatures. This means the slightly heated/dark panel melts the snow slightly, which slides down due to the angle in which it’s sitting. Along the same vein, the cold nature associated with snow is actually much better for the cells in the solar panel itself, as cells are more efficient in letting energy pass through when they are colder than when they are very hot!
For most Calgary homeowners, they're primarily concerned with the question, "does snow stop solar panels from working?" Knowing the answer to this question is crucial for Calgary homeowners to harness solar energy as a reliable and affordable source of energy. After all, knowing that your panels will work all year round is a great argument for using them! And, being aware that your roof and shingles, solar panels, and entire home is going to go through an annual ice-melt without the security of an unproblematic energy source does seem like a no-brainer.
Understanding Solar Panel Functionality in Winter
Solar panels work by converting sunlight into usable electricity, a process known as the photovoltaic effect. Photovoltaics don't need hot weather to work - in fact, high heat levels can make solar panels less efficient. So, despite the cold weather in Alberta in winter, solar panels can be surprisingly productive, making them a great choice for the province's households and businesses alike.
The quality of winter Sun is a huge factor. Even though daylight hours are shorter at this time of year, the Sun emits a very intense light in winter, and in clear conditions, this can mean prolonged periods of high solar production. There's also snow to consider - solar panels can benefit from high albedo (the reflection of the Sun's light) in their near environment. In snowy areas like Alberta, in certain conditions, solar panels can be up to 80% more productive in winter than they would be on a summer day.
The province's geography gets a lot of homeowners in Alberta wondering about solar panel installation in winter. Once you've done some research into the province's (and the wider federal Canadian) commitment to renewable energy supplies, the Sun might as well be rising on a very sustainable future. Solar power could be a great part of the energy mix in an average Alberta home - moving away from our "fossiled" view of our oil-buried predecessors. Technology is finally bringing lighter and more efficient panels onto the market, so perhaps now might be a better time to go solar than previously. Solar panels and winter - there's a bright thought!
The Impact of Snow on Solar Panels
The build-up of snow can severely affect the performance of solar panels. First, it blocks sunlight. Solar panels require sunlight to produce electricity, and a layer of snow prevents sunlight from reaching the panel. The intensity of this effect depends both on the thickness of the snow and the tilt of the panels; while a thin layer of snow may still allow some sunlight to pass, flatter panels will allow more snow to accumulate.
The total amount of snow also affects the structural integrity of the solar system. Under large enough loads, the panels may bend or even break. This is particularly concerning in areas that receive snow throughout the winter; the sun may not have a chance to remove the snow from the panel before causing structural problems.
So while a solar panel with snow on top of it will not produce electricity, it will not prevent a solar panel from producing electricity permanently, even if the entire system becomes buried. The solar panels will only cease production while snow is actively falling. In fact, there will have a built-in system to raise the temperature of the panel to remove the snow.
Benefits of Snow for Solar Panels
Snow and solar are a winning combination, as snow can actually help panels be more efficient in several ways. Snow has an insulating effect, so when it initially piles up on solar panels, it keeps them cool so they won’t overheat. In addition, snow naturally gets panels cleaner. When it melts off the surface of the panels, any dirt or dust that accumulated will be washed away with it to help panels run at their most efficient, capturing the most solar energy possible.
Additionally, the fresh, white color of snow works to more effectively reflect the sun and therefore increase solar energy capture. Thanks to what scientists call the albedo effect, more sunlight will be reflected, or bounced back up to, solar panels. This only adds to the other energy-generating benefits of snow on solar panels. Insomuch, the color of snow and panels is one of the ways that the solar and snow combination are a good thing to outdoor pleasures of the winter months.
Snow and solar panels interact in their own right, in every area where snowy months of the year are typical. Results are the same for solar panels for your home, be it a rooftop system or not, and for solar panels for your business, regardless of what each individual industry model might be otherwise. So, anyone that has a solar panel installation should get their own solar panel snow rake.
Case Studies and Real-Life Examples
Homeowners in Calgary use solar energy to power their homes...in the dead of winter. And what's more, many have actually had success doing so—with one even saying that their solar system generated over 70% of their energy needs (even during the winter)—all because of modern, more efficient solar technology.
So, you'd better believe that solar panels can work well in the snow. Because they usually can. In fact, when exposed to sunlight, your average solar panel will work "just fine"—producing on cloudy days about 80% of an energy yield of what you'd typically see from them—that is, if they're not totally buried under the snow, first. However, because it can seem to enhance the reflection that's all around them by themselves, large banks of snow (from Edmonton to Ontario, the BC lower mainland or almost everywhere—even Alberta), you'll find more often than not can actually help make most of that sunlight electricity even better—helping photovoltaics perform better in winter.
The article suggests that snow accumulation might actually enhance rather than disrupt the flow of PV efficiency. Because the snow itself can increase light exposure onto PV modules, it may have something of a mirror effect on your panels, especially if the majority of your PV system is distributed onto the rooftops of your Edmonton estate. Conversely, I assume that most of you live in places of the world that are exposed to a significant amount of yearly snowfall.
Of course, a sufficient amount of snowfall angled on your panels will offset the shape of your designated panels, leading to a particularly surprising lower energy production. However, once a higher temperature is achieved, it may cause a snow shedding of sorts to retract the actual amount of unmitigated snowfall onto the panels. Afterwards, it's reasonable to assume that your project performance is back to short-term normalcy.
Generally, very low temperatures seem to improve the efficiency of solar PV cells as exposure to long-term extremely warm temperatures is not too uncommon of an occurrence. Basic science confirms that PV panels tend to improve on functioning performance based on "cold and sunny weather."
