Yes, solar panels work in winter in the UK. Solar panels generate electricity from daylight rather than heat, which means they can continue producing energy during autumn and winter, even on cold, cloudy and overcast days.
However, solar panels will generally produce less electricity during winter than they do in summer. That's mainly because the days are shorter, the sun is lower in the sky and there is less solar energy available.
So, while your solar panels don't suddenly stop working when the clocks go back, it is useful to understand how their performance changes throughout the year – and how battery storage can help you make better use of the energy you generate.
Do Solar Panels Work on Cloudy Days in the UK?
Yes. Solar panels work on cloudy days, although they won't normally generate as much electricity as they would under clear, bright conditions.
Solar photovoltaic (PV) panels convert light into electricity. Although direct sunlight provides excellent conditions for solar generation, panels can also use diffuse daylight that reaches them through cloud cover.
That's particularly important in the UK, where cloudy weather is hardly unusual.
The Energy Saving Trust confirms that solar panels continue to generate electricity on cloudy days because they can absorb visible light and wavelengths that pass through clouds.
Do Solar Panels Need Direct Sunlight?
No. Solar panels do not need direct sunlight to generate electricity.
They need light.
That's why a solar PV system can continue generating electricity when it's:
Cloudy or overcast
Cold
Raining
Autumn or winter
Bright but not particularly sunny
Output will vary according to the amount of available light, but an overcast sky doesn't simply switch a solar system off.
Do Solar Panels Work in Cold Weather?
Yes – and cold temperatures themselves aren't the reason solar generation falls during winter.
Solar PV panels can actually operate efficiently in cooler temperatures. Very high panel temperatures can reduce photovoltaic efficiency, so a bright, cold winter's day can provide good generating conditions.
What limits overall winter generation is primarily the reduction in available solar energy, including shorter daylight hours and the lower position of the sun in the sky. The Independent
Are Solar Panels Less Efficient in Winter?
This is where there's an important distinction between efficiency and total generation.
Cold weather doesn't necessarily make a solar panel less efficient at converting the light that reaches it into electricity.
But considerably less solar energy is available during a typical UK winter day than during a long summer day.
Consequently, total daily and monthly solar generation is normally much lower in winter, even though the panels themselves are still working perfectly well.
This seasonal variation is normal and should be considered when a solar PV system is designed and its expected annual generation is calculated.
How Much Electricity Do Solar Panels Generate in Winter?
There isn't one figure that applies to every UK solar installation.
Winter solar output depends on factors including:
The size and specification of your solar PV system
Your location in the UK
Roof orientation and pitch
Shading from trees, buildings or other obstructions
Local weather conditions
The time of year
The design and efficiency of the system
That's why it's better to consider expected annual solar generation rather than judging a system by what it produces on a particularly dark December afternoon.
Current UK guidance consistently shows a significant seasonal difference between summer and winter generation, principally because of reduced daylight and solar irradiance. The Independent
Do Solar Panels Work in Low Light?
Yes, but their output will be lower.
Modern solar panels can generate electricity from relatively low levels of daylight. However, the amount of electricity generated is directly influenced by the amount of usable light reaching the panels.
A dull winter morning therefore won't normally produce the same amount of electricity as a bright summer afternoon.
The important point is that low generation isn't the same as no generation.
Do Solar Panels Work in the Rain?
Yes.
Rain doesn't prevent solar panels from working. If there is daylight reaching the panels, they can continue generating electricity.
Heavy cloud associated with rain may reduce the amount of available light and therefore reduce generation, but the rain itself isn't preventing the photovoltaic cells from operating.
Rain can also help wash away some surface dust, pollen and debris from panels. The Independent
Do Solar Panels Work in Snow?
Yes, provided light can reach the solar cells.
A significant covering of snow can temporarily reduce generation because it prevents light reaching the panel surface.
Fortunately, prolonged heavy snow isn't a regular occurrence across much of southern England, and the angle of roof-mounted solar panels can help snow clear from the surface.
You should not climb onto your roof to clear snow from solar panels. Aside from the risk of damaging the panels, working at height in icy conditions presents an obvious safety risk.
Do Solar Panels Generate Electricity in Autumn?
Absolutely.
Autumn is simply part of the gradual transition from the higher solar generation of summer towards the lower generation of winter.
As daylight hours decrease, you should expect solar generation to reduce too. But your panels will continue producing electricity whenever sufficient daylight is available.
And there are still plenty of uses for that electricity.
Including some slightly less essential ones...
#BeMoreChris 🎃
As usual, Chris got a little too excited about Halloween this year and bought the largest inflatable pumpkin he could find.
Unfortunately, an enormous glowing pumpkin isn't particularly impressive during daylight.
Luckily, Chris's solar panels can generate electricity during the day and, when surplus solar is available, his home battery can store that energy for use after dark.
So when night falls, stored energy can contribute towards keeping his unnecessarily enormous pumpkin glowing.
#BeMoreChris
There's actually a serious point behind Chris's questionable Halloween purchasing decisions.
The electricity generated by solar panels isn't always produced at the same time that you want to use it.
And that's where battery storage becomes particularly useful.
Does Battery Storage Work in Winter?
Yes. A home battery works throughout the year.
During periods of good solar generation, electricity generated by your solar panels is first available for your home to use. Depending on the system configuration, surplus electricity can then be stored in a battery rather than immediately exported to the grid.
That stored energy can be used later – including in the evening after your solar panels have stopped generating.
Battery storage therefore gives households greater flexibility over when their solar-generated electricity is used.
Energy Saving Trust similarly notes that battery storage can retain surplus daytime solar generation for use when your home is generating less electricity, such as at night. Energy Saving Trust
Can Solar Batteries Charge in Winter?
Yes.
If your solar panels generate more electricity than your home is consuming at that particular time, compatible battery storage can use that surplus electricity to charge.
However, because overall solar generation is lower in winter, there may naturally be less surplus solar available to charge your battery than during spring and summer.
That doesn't mean the battery becomes redundant.
Modern battery systems can provide considerably more flexibility than simply storing surplus summer solar.
Battery performance can also be affected by very low temperatures, particularly where a battery is installed outside or in an unheated space. If you already have battery storage, read our guide to how to protect battery storage in winter for practical advice on cold-weather protection and winter operation.
Can You Charge a Solar Battery From the Grid in Winter?
Many modern battery storage systems can be configured to charge using electricity from the grid as well as solar PV.
This can be particularly useful during winter.
Depending on your battery system, electricity tariff and configuration, it may be possible to charge your battery during a cheaper off-peak electricity period and then use that stored electricity when grid electricity is more expensive.
That can change the role of your battery throughout the year.
In summer, you might predominantly use it to capture surplus solar generation.
In winter, when less surplus solar is available, off-peak grid charging and tariff optimisation may become more important.
Whether this is suitable – and how the battery should be configured – will depend on your individual system and electricity tariff.
Are Solar Panels Worth It in Winter?
Solar PV shouldn't really be judged on winter alone.
A solar installation is designed to generate electricity throughout the year, with substantially more generation expected during spring and summer and lower generation during autumn and winter.
The more useful questions are:
How much electricity is the system expected to generate annually, how much of it can you use yourself, and how effectively can any surplus generation be stored or exported?
Your household's consumption pattern matters too.
Someone who works from home and uses considerable electricity during daylight hours may use solar energy differently from a household that's empty throughout the working day.
Battery storage, EV charging, heat pumps, air conditioning and other significant electrical loads can all influence the most appropriate system design.
How Can I Get More From My Solar Panels in Winter?
You can't make December behave like June, but you can make better use of the electricity that your system does generate.
Monitor your system. Understanding when you're generating and consuming electricity makes it easier to identify opportunities to use more of your own solar energy.
Move flexible loads where practical. Running appliances such as washing machines and dishwashers during periods of solar generation can increase self-consumption.
Review your battery settings. The most appropriate charging strategy in July may not necessarily be the best strategy in December.
Review your electricity tariff. If your battery supports grid charging, an appropriate time-of-use tariff may provide additional opportunities during periods of lower solar generation.
Keep an eye on shading. The sun sits lower in winter, so surrounding trees and buildings may affect your panels differently from summer.
And if your system's generation suddenly looks significantly different from what you'd normally expect for the time of year, it's worth investigating rather than assuming it's simply because it's winter.
What Affects Solar Panel Generation Throughout the Year?
Season is only one factor.
The performance of a solar PV system is influenced by the property itself, including available roof space, roof orientation, pitch and shading.
That's why two neighbouring properties can potentially have different solar generation profiles.
It's also why UK Green Energy Installations doesn't approach solar design with a predetermined number of panels or a one-size-fits-all package.
We look at the individual property, available space and the customer's energy requirements before recommending a system.
Should I Wait Until Spring to Install Solar Panels?
Not necessarily.
Installing solar PV during autumn or winter means your system can already be operational as solar generation begins increasing again towards spring and summer.
There may also be a DNO application required before certain solar or battery systems can be connected.
The process and timescale depend on the proposed system and local Distribution Network Operator, so it's something worth considering when planning an installation rather than waiting until the first sunny week of spring.
Solar Panels and Battery Storage in Hampshire, Surrey and Berkshire
UK Green Energy Installations designs and installs solar PV and battery storage systems for homes across Hampshire, Surrey and Berkshire.
We're MCS certified, a Tesla Approved Installer, Platinum GivEnergy Installer and Myenergi Product Champion, and we install systems from a range of leading manufacturers.
Rather than simply looking at how many solar panels will fit on a roof, we consider how the system will work for the household throughout the year – including solar generation, electricity consumption, battery storage and future requirements.
Because solar panels do work in winter in the UK.
They just don't produce the same amount of electricity in December as they do in June – and a properly designed solar and battery system should take that into account from the beginning.
Contact UK Green Energy Installations