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In short, yes! Shorter days and overcast skies might raise doubts, but solar panels work in all seasons – including winter. Remember, solar panels need light, not heat, to generate electricity. Thanks to modern technology and diffused light capture, they continue to provide clean energy throughout the colder winter months.
Let’s look at the data to see how solar generation performs in the UK through the winter months.
Here, we can see the overall solar generation to the UK’s electricity grid through 2024, giving us a good view of how solar generation changes through different times of the year.
Source: Energy Dashboard
Here, we can see the same trend from an individual home set-up:
Source: Energy Stats
With cold temperatures not impacting solar panels, the decline in output is due to the number of daylight hours, the lower angle of the sun and the frequency of cloudy days experienced in the UK winter months compared to summer. The UK averages around 8 hours of daylight in winter compared to 16 hours in summer. That’s 50% fewer hours of daylight, which will immediately result in half the amount of solar production. As we can see above, when you factor this in, with the lower sun and cloudier days, winter output can drop to around 15.0% of that experienced in peak summer months.
Regarding solar panel efficiency, cold weather helps improve panel efficiency by reducing internal resistance. Solar panel output can vary in different temperatures (known as the temperature coefficient) but only declines in warmer weather, meaning the panel works more efficiently in colder temperatures.
Regarding panel efficiency, this temperature coefficient means that for every 1oC above 25oC, solar panels lose around -0.3% to -0.5 %. However, this is not an issue in the cold, meaning they perform no matter how cold it gets.
Another question many ask is, “How does daytime supply marry up to nighttime demand” during the more extended and darker nights? That is a valid question. However, it’s not limited to winter. Overall, homes with solar panels export around 50-60% of their generation. The amount they export is lower through winter at around 40-50% compared to 70% in summer. With the ‘Smart Export Guarantee’, energy tariffs are available for consumers to sell excess electricity back to the grid at around £0.15 per kWh. This income helps offset the cost of electricity you import from the grid, i.e. you’re now selling excess electricity to the grid for £0.15 per/kWh and then importing it for around £0.25 per/kWh. Therefore, the net cost for your solar electricity is around £0.10 per/kWh – a saving of 40%.
However, suppose you combine your solar panels with a Battery Storage Unit, such as the Tesla Powerwall. In that case, you can charge your battery during the day using your solar panels and then use this electricity through the night, further improving your savings and reducing your carbon footprint.
Whilst the UK continues to invest in solar at an individual, business, and grid level, we can see that the UK as a whole is generating 240GWh (240,000,000kWh) of electricity through December, which is enough to power almost 900,000 homes for the entire month.
If we look at other European countries with a similar latitude to the UK, this is how much of their electricity is now being generated by solar:
| Country | Solar % of Total Electricity |
| Netherlands | 17.7% (6th highest in Europe) |
| Germany | 14.8% |
| Belgium | 11.9% |
| Denmark | 11.3% |
Source: Our World in Data
Most panels have a temperature coefficient of around -0.35% per °C. That means they lose less performance to heat in colder weather, improving energy conversion rates.
For example, panels operating at 5°C will be more efficient than those at 25°C. This is another reason solar power performs well, even in places like Norway and Canada.
Even when the skies aren’t clear, scattered light still powers PV cells. However, on cloudy winter days, solar panels may produce 30–50% of their usual output.
Snow can:
Pro tip: Consider snow-friendly mounting angles and anti-reflective glass coatings for winter climates.
Despite the lower hours of sunlight, winter still brings measurable savings.
Depending on where you are in the UK, your electricity from the grid will cost around £0.25 per kilowatt hour (kWh). The average UK home will use around 9kWh per day during the winter months. During winter, a standard 4KW solar panel system produces between 3 and 6 kWh per day. It is not enough to make the average daily amount of 9kWh per day, but it is a decent enough chunk. Using this free solar energy from your panels would save you around £30 per month on your electricity bills.
When it comes to the environment, every little helps. Every kWh of energy you can use from the sun is another kWh you’re not pulling from the UK grid, which during November – February 2024, had 34.5% of electricity generated by burning fossil fuels in the form of gas.
Regular care keeps your system running smoothly when it matters most.
Monitoring systems help:
Some panels are simply built better for cold, cloudy climates.
| Panel Type | Efficiency | Winter Suitability |
| Monocrystalline | 15–22% | Best in low-light, compact, but higher cost |
| Polycrystalline | 13–16% | Good for milder climates, more budget-friendly |
| Thin-Film | 10–12% | Works in extreme cold, lower efficiency |
| Bifacial | 16–20%+ | Leverages snow reflection, ideal in snowy zones |
Monocrystalline panels with anti-reflective glass are ideal for UK winters.
Winter isn’t a barrier – it’s just another season your panels are ready for. With the right setup and proactive care, your solar system can:
Just remember:
📞 Ready to upgrade or install a winter-ready system? The Solar Co can help.
The short answer? Yes – they 100% do.
When you think of solar panels, you might imagine the need for endless sunny skies, but that’s unnecessary. Even in cloudy weather, solar panels generate electricity from natural daylight, meaning diffused sunlight, i.e. sunlight that is shining through clouds, works just fine.
The UK’s daylight hours, which vary from 8 to 16 hours depending on the time of year, and mild climate make solar energy a viable year-round solution.
To prove this claim, let’s look at some real-life data to show how UK solar generation compared on two very different days regarding the weather.
Friday, 9th May 2025 – Sunny day across the UK.
Here, we can see the total solar generation to the National Grid in Gigawatt Hours (GWh).
Thursday, 6th June 2025 – cloudy and wet across the UK.
Here we can see the cloud cover across the UK:
And here is the comparable total solar generation to the National Grid in Gigawatt Hours (GWh) on this cloudy day.
Let’s compare these two days’ half-hourly generation (showing every hour for ease). We get the following data showing the overall average variance in solar output on a cloudy day across the UK, which was 43.6% of a sunny day with no clouds.
| Time | Friday, 9th May (Gigawatts) | Thursday, 6th June (Gigawatts) | Variance % (Cloud Vs Sunny) |
| 07:00am | 0.622 | 0.246 | 39.5% |
| 08:00am | 2.321 | 0.897 | 38.6% |
| 09:00am | 4.724 | 1.621 | 34.3% |
| 10:00am | 7.642 | 2.624 | 34.3% |
| 11:00am | 10.150 | 3.763 | 37.1% |
| 12:00pm | 12.055 | 4.564 | 37.9% |
| 13:00pm | 12.901 | 5.514 | 42.7% |
| 14:00pm | 12.721 | 6.203 | 48.8% |
| 15:00pm | 12.049 | 5.735 | 47.6% |
| 16:00pm | 10.645 | 5.510 | 51.8% |
| 17:00pm | 8.731 | 4.176 | 47.8% |
| 18:00pm | 6.129 | 2.993 | 48.8% |
| 19:00pm | 3.602 | 1.916 | 53.2% |
| 20:00pm | 1.566 | 0.751 | 48.0% |
Source: https://www.energydashboard.co.uk/historical
Here we have images from a The Solar Co customer proudly showing us how, despite cloudy conditions, his solar set-up was still generating enough electricity to meet his demand and producing a little extra to sell back to the grid.
Whilst this data shows a drop in solar generation, as you would expect, solar panels continue to generate electricity even on cloudy days. Also, let’s not forget that if it rains, that will help clean the solar panels, removing dust and dirt that will otherwise start to reduce the panel’s efficiency.
The results shown above explain, in part at least, why record numbers of UK consumers are opting to invest in solar panels to reduce their energy bills and carbon footprint and ultimately help the environment. Latest data from the UK government shows how solar panel sales are surging:
Over 75% of solar panel installations have been domestic, and the remaining 25% commercial. Of the domestic installations, 80% are retrofitted to existing properties, and 20% have been installed on new builds.
In addition to producing free electricity all year round, most solar panels come with an output warranty of around 30 years. Depending on the quality of the panel, e.g. Monocrystalline or Polycrystalline, the loss of power output against the minimum peak power at standard test conditions should be around +80% after 30 years of use.
For context, if you have a system installed with an Annual Solar Energy Production of 5,000 kilowatt hours (kWh), your panels will be under warranty to still be producing +80% of that after 30 years which would equate to an Annual Solar Energy Production of 4,000 kilowatt hours (kWh). Remember, that is what the manufacturer is willing to put under warranty, so the reality is that output should be higher than this over a more extended period.
Several factors determine how efficient your system performs:
In terms of overall efficiency, solar panels can last for 25-30 years with the output of your panels only degrading by around 0.3% to 1.0% per year.
These factors mean a well-installed system will perform consistently – even in Winter.
Solar panels generate electricity without direct sunlight thanks to photovoltaic (PV) cells that absorb light, whether direct or diffused when the sun’s rays shine through clouds.
“Germany – with weather very similar to the UK – is one of the global leaders in solar energy production.”
Whilst output on overcast days drops to 10–50% of full sunlight levels, newer technologies and premium panels help improve efficiency and solar production.
Yes, Winter reduces solar output – but it doesn’t stop it. In the UK, we average around 12 hours of daylight each day, varying between 8 hours in the Winter and 16 hours in the Summer. For a more detailed breakdown, here is how many hours of daylight we see by month in the UK:
If we look at overall UK solar generation at a grid level, this also gives a good illustration of how your solar output performs throughout the year:
As we can see, solar output during Autumn/Winter will be lower (around 25.0% of your annual solar energy production), while your electricity consumption increases (around 57.0% of your annual electricity consumption). Therefore, to enhance your setup even further, you can pair your solar panels with a battery storage unit to store your solar power for later in the day when the nights draw in.
Investing in solar is a strategic move, environmentally and financially.
| Solar is right for you if… | You may reconsider if… |
| You live in the UK and want to cut bills | You want full power output in Winter |
| You care about reducing carbon emissions | You have poor roof orientation or shading |
| You want protection from volatile energy costs | You’re expecting 100% off-grid living |
| You want long-term investment value | |
| You have suitable roof orientation, i.e. south facing | |
| You want energy security |
Even in cloudy weather, UK homeowners can benefit from solar power thanks to efficient technology, smart installations, and long daylight hours – up to 16 hours during Summer months.
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Here at The Solar Co., we have extensive experience installing integrated solar panels, alongside more traditional on-roof setups in the South-East. We’ve put together a comprehensive guide that addresses some of the questions we most often receive from customers. This will help you decide if they are right for you.
Integrated solar panels, also known as in-roof solar panels, seamlessly blend into a building’s roof. Unlike conventional solar panels that sit on top of an existing roof, integrated panels become part of the roof itself, providing a more aesthetically pleasing finish.
In this guide, we’ll cover the following:
Advantages:
✅ More aesthetically pleasing
✅ Likely to add even more value to your property
✅ Prevents birds nesting behind panels
✅ Saves money on meshing
✅ Will save money on tiles if done at build stage
Disadvantages:
❌ Increased costs to install retrospectively
❌ Impact on efficiency during hotter periods
❌ Designated Flashing Zones: Integrated panels require flashing zones around the system’s border, limiting usable space and often resulting in fewer panels compared to on-roof systems.
❌ Rigid Layout Constraints: Fixed mounting trays must align perfectly, preventing panel staggering or orientation changes, which limits layout flexibility.
The cost of integrated Solar Panels will vary depending on whether they are added to a new build or retrofitted into an existing roof.
Retrofitting will naturally involve removing a large percentage of the existing tiles and replacing them with the in-roof solar panels. This will incur a larger cost due to the added manual labour and extra expense associated with disposing of the removed tiles. Where the roof is already tiled, integrated solar panels generally cost an additional £150 – £250 per panel compared to on-roof systems.
For new builds, they are integrated into the roof at the build stage. There are additional costs to integrate them, around £100-£150 per panel versus a traditional set-up, but there is something important to bear in mind.
Each solar panel typically covers around 2m² meaning that for every panel installed there is a relative saving on the roofing cost of that area, i.e. you will need fewer tiles and labour.
Given that installed slate tiles cost approximately £160 to £275 per m² and concrete tiles around £60 to £80 per m², the avoided expense of tiling 2 m² per panel can significantly reduce the overall cost difference, making integrated solar a cost-effective option.
Your roofer might not be inclined to tell you this!
Top-level, integrating your solar panels may reduce the efficiency of the system by 2-5%.
Let us explain why it’s difficult to provide a more precise number.
All solar panels lose efficiency when they are above a certain temperature, around 25c.
There are not many days in the UK when the temperature exceeds 25c, however note this is the temperature of the panel, not the air.
With Integrated solar panels sitting flush with the room, there is slightly reduced airflow to cool the panels. This reduced air could increase the temperature of the panel itself by 5c to 10c.
An individual panel may produce around 0.5% less power per Celsius above 25c, so on those days, the panels are likely to be 5% less efficient than a traditional on-roof solution.
On a hot August day, if you exported 30kWh with a traditional on-roof solution, you would export 28.5kWh with an integrated set up. At an export rate of 15p per kWh, that would be £4.27 rather than £4.50. That is a 23p difference.
There will only be so many days of the year when this becomes relevant, owing to the seasonal climate of the UK.
The loss of efficiency should be balanced against the additional value it adds to the property.
This graphic gives you a good example of how the finish can differ:
Opting for integrated solar panels versus a traditional on-roof solution is likely to add even more value to your house.
Reduced electricity bills from a system already in place is very appealing to many prospective buyers. Any installation therefore is likely to increase the value of your property.
However, integrated panels provide a very nice aesthetically pleasing finish, which is likely to be preferred by the majority, and therefore valued even more.
Numerous studies show properties with efficiency upgrades (such as solar panels) sell for as much as 15% more. This could be caveated that someone who has invested in solar panels in their home are likely to have made other investments to command a higher selling price, but there is plenty of evidence that it’s a key part in selling a home for a bigger price, and faster.
There is a good chance that the extra cost of integrating the panels, and then the slight drop in efficiency is completely offset by the extra value it adds to the house because of the better finish.
Get them if:
You want your solar panels to look seamless and are happy to compromise on a small amount of efficiency during some months and have the budget to integrate them.
Don’t get them if:
You think a traditional on-roof installation looks fine, want to maximise the power you generate, want as many panels as possible and want to keep costs as low as possible.
If you’re based in the South East, then contact The Solar Co and get a quote.
We install both on-roof and integrated solutions and can help advise on what is right for you.
The Solar Co designs the most optimal systems for each customer. For each system we design, we do the following
Give us a call, WhatsApp or an email and let us help you.
We’re thrilled to announce that The Solar Co has been shortlisted for a national Which? Award in the category of Renewables Installer of the Year!
Which? is one of the UK’s most trusted consumer organisations, known for standing up for high standards, transparency and great service. Each year, their awards recognise companies that go the extra mile for their customers – and we’re incredibly proud to be one of just a handful of businesses highlighted in the renewables category.
Based right here in Bromley, we’ve worked hard to help local homeowners take control of their energy bills with expertly installed solar panels and battery systems. From initial consultation through to aftercare, we pride ourselves on being professional, transparent and friendly – and we’re proud to have received outstanding reviews from our customers on Google Maps and Trustpilot.
“We’re incredibly proud to be recognised by Which?,” said George, co-founder of The Solar Co. “It’s a name people across the UK associate with honesty and high standards, and this nomination means a lot to us and to our customers.”
“This is a real moment of pride for the whole team that has made this possible,” added Mark. “We’ve worked hard to build a company that genuinely helps people—whether it’s saving money on bills or doing their bit for the planet. To be shortlisted for a national award like this is a fantastic recognition of that mission.”
Thank you to all of our amazing customers for your support. We’re proud to be representing Bromley on the national stage – and excited for what’s ahead!
Owning a Tesla is exciting, but understanding the nuances of electric vehicle (EV) charging can be a bit of a learning curve. A common question among Tesla owners is: should I plug in my car every night? It’s a valid concern, as proper battery care is crucial for longevity and optimal performance. Let’s delve into the details and find the best charging strategy for your Tesla. We’re here to help you navigate the world of EV charging, so you can keep your Tesla running smoothly!
Teslas, like most EVs, use lithium-ion batteries. These batteries work by moving lithium ions between the anode and cathode to store and release energy. It’s a complex process, but the key takeaway is that these batteries, like all batteries, degrade over time.
Battery degradation refers to the gradual loss of a battery’s ability to hold a charge. Several factors contribute to this, including:
It’s important to dispel the myth of battery “memory.” Older battery technologies sometimes suffered from this issue, where repeated partial discharges would reduce capacity. Modern lithium-ion batteries don’t have this problem, so you don’t need to worry about fully discharging your Tesla’s battery regularly.
There are definite advantages to plugging in your Tesla every night:
While plugging in every night offers convenience, there are potential drawbacks:
Luckily, Tesla makes it easy to manage your charging habits. You can set charging limits within the car’s software, preventing it from charging beyond your desired percentage. I highly recommend taking advantage of this feature.
Here are some specific recommendations for Tesla charging:
Tesla offers a battery warranty that covers defects and excessive degradation. It’s important to familiarise yourself with the specifics of your warranty.
Here are some additional tips for maintaining long-term battery health:
Whether you should plug in your Tesla every night depends on your individual driving habits and needs. While there’s no single right answer, understanding the principles of battery chemistry and following best charging practices can help you maximise your battery’s lifespan and ensure optimal Tesla performance. By implementing the advice in this guide, you can confidently manage your Tesla’s charging and enjoy the benefits of electric vehicle ownership.
If you are looking for a certified Tesla installer to help you with an EV Installation or a Tesla Powerwall installation then be sure to get in touch today to learn how we can help you achieve your perfect home or business!
Did you know that the amount of solar energy that hits the Earth in just one hour is more than the entire world’s energy consumption for a whole year?! That’s mind-blowing, isn’t it? Imagine harnessing that incredible power to fuel your everyday life. It’s not science fiction—it’s solar energy! But how exactly do those sleek panels on your roof translate sunlight into usable electricity for your home? It’s a fascinating process involving several key components. I’m here to break it down for you in simple terms, so you can understand the journey from sunlight to powering your lights, appliances, and everything in between. Let’s dive in!
At the heart of every solar system is, of course, the solar panel itself. These panels are like tiny powerhouses, working their magic through something called the photovoltaic effect. This fancy term simply means that when sunlight (photons) hits the silicon in the solar cells, it knocks electrons loose, creating an electrical current. This current is direct current (DC) electricity, which flows in one direction.
Now, let’s talk about what these panels are made of. They’re built from multiple layers, with the crucial part being the silicon cells. These cells are arranged in a grid-like pattern and sandwiched between protective layers of glass and other materials. This construction protects the delicate silicon and ensures the panels can withstand the elements.
You might have heard of different types of solar panels. The most common are:
Here’s where things get interesting! Remember that solar panels produce DC electricity, but most of our household appliances use alternating current (AC) electricity, which flows in alternating directions. This is where the inverter comes in. It’s like a translator, converting the DC power from the panels into AC power that your lights, fridge, and telly can use.
There are a couple of main types of inverters:
Inverter efficiency is crucial. A more efficient inverter means less energy is lost during the conversion process, maximising your solar system’s output.
Once the inverter has converted the DC power to AC power, it needs to be integrated into your home’s electrical system. This is done by connecting the inverter to your electrical panel (also known as the breaker box or fuse box).
Your electrical panel is the central hub of your home’s electrical wiring. It distributes power to different circuits throughout your house. The connection from the inverter is made through a dedicated breaker, which protects the system from overloads and short circuits.
Here’s another cool bit: net metering. If your solar system produces more electricity than your home is using, the excess energy is sent back to the grid! This is often measured by a bi-directional meter that tracks both the electricity you use from the grid and the electricity you send back. In many areas, you can receive credits on your electricity bill for this excess energy – how brilliant is that?!
Wouldn’t it be great to see how much energy your solar panels are generating? Well, you can! Modern solar systems come with monitoring systems that track energy production in real-time. These systems can range from simple displays on the inverter to sophisticated online platforms and mobile apps.
Monitoring is incredibly useful. It allows you to:
Some systems even integrate with smart home technology, allowing you to control appliances and manage your energy consumption more efficiently. Imagine turning off your lights remotely or scheduling your washing machine to run when solar production is at its peak!
Now, a very important point: safety. Working with electricity can be dangerous, so it’s absolutely crucial to have your solar panels professionally installed. Qualified solar installers have the expertise and training to ensure the system is installed correctly and safely, adhering to all electrical codes and regulations.
Here are a few safety precautions related to solar panel systems:
Don’t forget about permits and inspections! Before you install your system, you’ll likely need to obtain permits from your local council. After installation, an inspection will be carried out to ensure everything meets safety standards.
Rather than risk your life or damaging your property – be sure to get in touch today with one of our expert team members. As a MCS Certified Solar Installer we will help make sure that your Solar System is designed perfectly for your personal needs and ensure the installation happens hassle free with a promise of maintenance and support after the job is done! Reach out today to hear how we can help!