Are you considering investing in solar power and are wondering do solar panels work in the winter? The short answer is yes! Solar panels can still generate electricity in the winter.

However, data shows that energy generation can drop to an eighth of what it would be on a summer day, so choosing solar panels designed to optimise energy production all year round is essential.

This guide explores how solar panels work in the UK during the winter, how winter weather affects solar panels, and how you can improve performance during those cold, overcast days.

Pro tip: Avoid upsells and confusing packages—choose a provider with a clear, fixed-price quote that won’t change. Heatable, a Which?-approved solar installer, offers transparent pricing with no surprises.

Quick Takeaways:

• Solar panels rely on daylight and can still generate power in winter conditions.
• Winter can affect performance through shorter days, a low sun angle, and a cloud or snow cover.
• The cold temperature in winter can help enhance solar panel efficiency.
• You can improve panel performance in winter by adjusting the tilt, removing snow, debris, and obstructions and investing in microinverters.

How Do Solar Panels Work in the Winter?

Knowing how solar panels work can help you understand how they can still generate electricity in the winter.

Solar panels rely on daylight or atmospheric light and not heat from the sun to generate energy. The panels consist of photovoltaic (PV) cells that capture and convert light into electrical energy.

The cells are crafted from layers of semiconducting material like silicon. They have properties that allow them to generate an electric current when light particles called photons hit the surface of the solar panel.

Contact with light triggers a reaction that knocks electrons free from their atomic bonds within the cells, generating an electrical charge.

Since the cells respond to light, solar panels can still harness enough energy to produce electricity from the low light of a gloomy or overcast winter day.

Thanks to technological advancements, some high-performance models are designed for efficiency in low-light conditions to help maximise energy generation.

How Does Winter Affect Solar Panels?

The winter weather can cause solar panel performance to dip due to various factors. These include:

Shorter Days

Winter is characterised by fewer daylight hours with the sun rising later and setting earlier. Daylight hours can drop to around 7 to 8 hours per day in winter in the UK compared to 16 to 17 hours in the summer.

This means light only hits the panels for a short period, leading to significantly less energy production.

Lower Sun Angle

The sun is lower in the sky during winter months, meaning direct light has to pass through more of the atmosphere before reaching the solar panels.

This reduces the amount of energy they can generate and this is exacerbated by factors like shading from nearby trees or structures.

Cloud Cover

Although clouds can’t halter electricity production entirely, they can diminish the performance of the panels.

Cloudy and overcast skies will block much of the already weak winter sunlight from reaching the panels. Increased cloud frequency can further reduce energy production.

Snow Cover

Thick snow can cover your solar panels in a layer of snow, preventing light from reaching the PV cells. Accumulated snow can also add weight to the panels and decrease efficiency.

However, heavy snow is rare in the UK and any light snow will slide off slanted panels or quickly melt. The melting snow can actually help your panels by removing any dirt or debris.

Do Solar Panels Operate in Cold Temperatures?

Yes! Solar panels rely on light and not heat so they’ll still operate even in cold winter temperatures. Cold temperatures are actually an upside for solar panels since it allows them to operate more efficiently.

Like most electrical equipment, solar cells function better when the temperature is lower and where heat-induced performance issues are low.

The cold temperature reduces resistance and allows the electrons within the cells to move more freely, boosting power generation capacity.

More electricity is generated within the cell when exposed to light, allowing your panels to make the most of the few daylight hours in winter.

How To Improve Solar Panel Performance in the Winter

There are a few actions you can take to improve the performance of your solar panels during the winter. These include:

Adjusting the Panel Tilt and Orientation

Adjusting the tilt of your solar panels can help capture more sunlight since the sun is lower in the sky during the winter.

It will also encourage snow or rain to slide off more easily. Changing the orientation to ensure your panels face south can also ensure maximum exposure to the sun.

Manage Snow or Debris

Snow and debris can block sunlight and reduce energy production so ensure you keep your panels clean for maximum output.

Panels that are angled between 30-45 degrees generally handle snow better. You can also use a special snow rake or garden hose to clear the panels or hire a professional for the job.

Remove Obstructions

The sun’s low angle can cause new shading and obstruction issues during the winter. Evaluate and trim any nearby trees or structures that could cast shadows on your panels. Ensure that the installation site remains free from obstructions to maximise the amount of light reaching the panels.

Utilize Battery Storage

Invest in a solar battery to store excess energy produced during clearer days. You can then use the stored energy during periods of low production, such as on cloudy or snowy days, ensuring a more consistent power supply.

Although it doesn’t improve the solar panel performance, it can help you make the most of the power your panels generate.

Invest in Microinverters

The type of inverter you use can impact the performance of your solar panels during the winter due to the startup voltage needed.

The direct current (DC) electricity generated by solar systems must be converted to alternating current (AC) for home use and the process requires a minimum level of DC voltage to start up or activate.

DC inverters usually require from 80 to 200 volts to start operating while microinverters can operate at much lower thresholds and can require as little as 22 volts to start.

This can be useful in capitalising on minimal energy production and improving efficiency in low-light winter conditions.

Final Thoughts

Solar panels don’t rely on direct sunlight or heat to generate electricity and can still work in the winter. However, shorter days, a low sun angle, and cloud or snow cover can impact performance.

Fortunately, you can enhance power production through various actions like adjusting the tilt, removing snow, debris, and obstructions and investing in microinverters.

Sources and References:

• https://www.gov.uk/government/publications/renewable-energy-and-the-effects-of-wind-and-solar-droughts/how-well-do-we-understand-the-impacts-of-weather-conditions-on-the-uks-renewable-wind-and-solar-energy-supplies-html