Are Solar Panels Effective in Winter?

Solar panels have been around for a while now, and on the whole, we’re aware that by converting the sun’s light into electricity, we get a clean, carbonless energy source. 

But investing in solar panels for the first time can raise all sorts of questions like whether they’re effective in UK winter conditions. With UK winters lasting for 3 seemingly long months, but poorer weather conditions impacting us for around 4-5 months of the year, it’s a reasonable question to ask.

Ultimately, you want to know that you’re getting great value for money and there’s nothing worse than wondering if your new investment will be sitting idle for parts of the year.  

The great news is that solar panels work throughout all four of the UK’s seasons. Understandably, though, the lower levels of light in the winter months will impact the amount of electricity your solar panels generate. So, with that in mind, is it still worth investing in solar panels when you’re operating in a northern clime like the UK? 

How Do Solar Panels Function?

To get started, we need to understand how solar panels actually make electricity. 

Solar panels are made up of a number of photovoltaic cells (PV cells), sometimes known as solar photovoltaic cells. These solar cells are made from semiconducting materials, usually silicon. When sunlight shines on the cells, particles of daylight, AKA photons, cause electrons to get loose from their atoms, which is essentially a flow of electricity.

Visit our Guide to PV Solar Energy page for further information.

What Determines the Amount of Power Produced?

In short, the amount of power produced is dependent on how much sunlight is converted by your solar panels. In other words, the more sunlight the solar panels can absorb, the more power you’ll get out of them. 

There are a few factors that can improve the energy conversion rate:

• Quantity, Quality, Size & Location: The number, size, location and quality of the solar panels can all have a direct impact on the amount of electricity generated. It stands to reason that the bigger the surface area and the larger the number of panels, the more electricity can be produced. Similarly, positioning your solar panels to maximise their exposure to sunlight will give you the best performance. 
• Temperature: Your gut might tell you that solar panels need warm, sunny conditions to function effectively. However, it’s a common misconception that solar panels work better in heat. In reality, cooler conditions help solar panels operate more efficiently as electrons are at rest, which means that activating them with sunlight generates a bigger voltage difference. 
• Direct vs Diffuse Sunlight: Direct sunlight is where sunlight travels from the sun in a straight line, whereas diffuse sunlight is where the light has been scattered by particles in the atmosphere, such as clouds. Modern solar panels are capable of generating electricity under both conditions but work better under direct sunlight conditions. 

Although it’s true that no matter how many panels you have, your electricity output will be negatively impacted by shorter, wintery days, the output isn’t zero! Plus, you’ll find that cooler temperatures also mean your solar panels work more efficiently.   

Does Cloudy Weather Reduce Energy Production?

Solar panels actually work reasonably well in cloudy weather, despite the lower light conditions. Just how effective the solar panels are is highly dependent on the cloud density. The denser the clouds, the less sunlight the solar panels will receive.

Interestingly, rainy weather can help solar panels work better than dry, cloudy weather as the rain washes away dirt or dust gathered on the panels, which would otherwise block sunlight. 

When we’re all facing rising energy bills, no matter how small the output is on a cloudy day, having your own source of power means you won’t have to worry about energy prices fluctuating in the future. 

Do Solar Panels Work in the Winter With Snow?

When it comes to whether solar panels work in the snow, the answer is a little more complicated. 

At first glance, layers of snow covering your snow panel will prevent sunlight from reaching your solar panels, which means they’ll generate less (if any) electricity. However, that’s not the end of the story. 

Solar panels are typically made from dark, reflective glass and so this darker material absorbs heat from the sun much quicker than lighter-coloured surfaces. The result is that as the solar panels get warmer, the snow will melt.

Additionally, snow on the roof can even reflect sunlight back onto the panels, meaning the solar panels may benefit from more sunlight than on a non-snowy day. 

Do Solar Panels Ice Over?

Like anything that’s outside, solar panels can form ice on them. But don’t despair, all is not lost. 

Since ice is clear, there’s nothing to prevent sunlight from reaching the solar panels, so they’ll still work fine. Additionally, since solar panels are typically black, they’ll warm up quicker than other surfaces and help to melt the ice, which runs off due to the tilt angle. 

One possible issue is if water freezes within crevices of the solar panels as this may cause physical damage. However, if you always ensure that you buy high-quality solar panels from fully qualified solar panel installers, you can be confident that you’ll be getting long-lasting equipment and receive support if you do run into any problems. 

How Do You Take Care of Solar Panels in the Winter?

Now that we know that solar panels can work during the winter, it may be tempting to clean off snow, ice and other debris from your solar panels’ surfaces to try and boost electricity production. 

As tempting as that is, it’s not a recommended best practice unless you seek help from a professional solar panel cleaning service. The risks and hazards of being in slippery conditions far outweigh the benefits.

There are a few things that you can do to prepare your solar system to be ready for the winter. 

• If your solar panels have been installed in a movable frame, then you may wish to adjust the angle a little steeper in order to best capture the sunlight. 
• Ensure that you turn off or unplug any unused appliances during the day. This is less about using electricity and more about ensuring that you’re able to generate maximum power during daylight hours, whether storing it in a battery for use overnight or sending excess to the grid. 
• If you’re using a battery to store excess power, ensure that it’s properly insulated for the winter. Batteries tend not to fare as well in cold weather. 

Solar Energy Solutions From Mypower

Solar panels are not only viable during the winter, but also very helpful in our constant search to reduce the impact of energy price fluctuations on our business’ operating costs. At Mypower, we have over 10 years of experience installing commercial solar panels, solar panels on agricultural buildings, and even industrial solar panels.

Get in touch today to learn more about how Mypower can help you on your renewable energy journey.