This guide was last updated: April 2024‍

Installing solar panels on your roof can be a great way to make your home more energy efficient.

Not only will they reduce your energy bills, but they could also earn you money by selling unused electricity to the National Grid.

They’re a great way to cut your home’s carbon emissions, too. Each solar panel you fix to your home could save up to 900kg of CO2 per year. So if you have 10 panels, it’s like taking five petrol cars off the road.

Oh, and yes… the UK is sunny enough to make installing solar panels worthwhile!

How do solar panels work?

First, we need to address a common misconception. Solar panels probably aren’t what you think they are. And what you think they are is actually called a photovoltaic (PV) panel.

The key difference is that:

• Photovoltaic panels work by converting energy from the sun into electricity.
• Solar (thermal) panels work by converting energy from the sun into heat.

When most people think of solar panels, they’re really thinking about photovoltaic (PV) panels which are more common. We’ll focus most of our attention on PV panels in this guide.

But first, let’s look at the main differences between the two…

How do photovoltaic (PV) panels work?

As we know, photovoltaic panels work by converting energy from the sun into electricity. From there, the electricity is connected to your home’s electricity circuit to be used when needed. A battery can also be installed to store the energy generated by the solar panels for later use.

Photovoltaic panels work well during the day, even when it’s cloudy.

Here’s how a typical photovoltaic panel works in more detail:

1. Light from the sun hits the face of the solar panel.
2. Solar radiation is absorbed by a layer of silicon.
3. Electrons in the silicon move around, creating a direct electric current.
4. The direct current (DC) is fed to a solar inverter which converts it into alternating current (AC).
5. The AC current can be fed either to your home’s breaker box for immediate use or a battery for later use.

How do solar thermal panels work?

True solar panels - i.e. solar thermal panels - work by converting energy from the sun into heat. The heat is converted into hot water which is then transferred to your home’s hot water system. It’s then used to heat up your hot water tank’s water before being sent back to the solar panel to be heated up again.

Solar thermal panels only work well when the sun’s shining brightly enough to heat up the water.

Here’s how a typical solar thermal panel works in more detail:

1. Light from the sun hits the face of the solar panel.
2. Heat from the sun is absorbed by a special fluid, usually made up of water and antifreeze.
3. The heated water is pumped into a heat exchanger which sits inside your home’s water tank.
4. The heat exchanger heats up the water in your water tank, without the two liquids meeting.
5. The used solar fluid is pumped back to the solar panel for reheating.

What are the best solar panels?

All photovoltaic panels work by converting the sun’s energy into electricity. But this can be done in lots of different ways.

There are four main types of photovoltaic panel:

• Monocrystalline solar panels
• Polycrystalline solar panels
• Passivated Emitter and Rear Cell (PERC) panels
• Thin-film solar panels

The most common types of panels used to power people’s homes are monocrystalline and polycrystalline.

The following chart shows their main differences.

Neither monocrystalline nor polycrystalline panels are ‘better’ than the other. The type that’s best for you will depend on your unique circumstances.

Have a small home in an area that gets hot in summer? Monocrystalline panels might be better for you.

Have a large home in an area that stays cool in summer? Polycrystalline panels might be better for you.

But it’s not quite as simple as that. You’ll also want to consider the upfront cost, the amount of electricity you want to generate, whether the panel’s appearance suits your home and how much sunlight your roof gets per day.

Which type of solar panel is best for you is something you’ll need to think about.

Solar panel brands

There are lots of manufacturers of solar panels. And that’s good. It means there’s likely to be much more innovation and a further fall in prices as they compete with one another.

Popular solar panel brands in the UK include:

• Canadian Solar
• JA Solar
• Panasonic
• Sharp
• Solarcentury
• SunPower
• Suntech
• Trina
• Viridian
• Yingli

How much energy does a solar panel produce?

A single photovoltaic panel operating in ideal conditions can generate up to around 400 watts per day. That’s enough to power a modern TV for around three hours, or provide around 5% of an average house’s daily electricity usage.

But there are lots of things that will impact how much energy a solar panel will produce, including:

• Panel type (e.g. monocrystalline or polycrystalline)
• Hours of sunlight (the more, the better)
• Roof direction (south is better)
• Roof angle (35° is best)
• Temperature (ideally not too cold or hot)

So it really depends on which panel you buy, what the weather’s like (remember, this will change throughout the year) and the position of your roof.

Use the following calculation to work out how many kilowatt hours (kWh) of energy a photovoltaic solar panel can produce in a day:

• The size of the panel in square metres
• * 1,000
• * the panel’s efficiency percentage
• * the number of sunlight hours in a day
• / 1,000

Do clouds affect solar panels?

Photovoltaic panels are affected by cloud cover, but not as much as you might think! It largely depends on the thickness of the cloud, but a panel’s efficiency could be reduced by around 10% to 25%.

This is great news for those of us living in the UK since a 400-watt photovoltaic panel still might produce around 300 watts on even the cloudiest of days.

Does rain affect solar panels?

Photovoltaic panels aren’t directly affected by rain but they are affected by the clouds that disperse rain. So they should be able to generate a good amount of electricity even during a downpour.

Ironically, a photovoltaic panel won’t generate more electricity if it’s struck by lightning.

Does roof direction affect solar panels?

The direction solar panels face is important because they work best when they’re directly facing the sun.

Because the UK is in the Northern Hemisphere, the optimum direction for solar panels to face is south (towards the equator).

But don’t worry if your only available roof space is north-facing. The panels will still be able to generate around 68% of their potential, making them worth considering.

How many solar panels do I need?

In theory, you’d need around 22 400-watt photovoltaic panels to power the average home. That’s because the average home uses around 8,800 watts of electricity a day.

But in practice - and assuming your home has space for 22 panels on your south-facing roof - the panels’ output will vary depending on the weather. So you’d need even more to provide all your electricity needs all year round.

Most people don’t install enough solar panels to go completely ‘off-grid’. Instead, they install what they can.

This depends on:

• The size of their roof.
• The direction of their available roof space.
• The cost of installation.

So a smaller terraced home might install 12 400-watt panels across its south and north-facing roofs, generating up to 4,000 watts a day (remember, the north-facing roof will generate around 68% of its potential).

But a larger detached home might install 24 300-watt panels on its south-facing roof, generating up to 7,200 watts a day.

Perhaps the question shouldn’t be, “How many solar panels do I need?” but rather “How many solar panels are right for my home?”

How much are solar panels in the UK?

There are several costs associated with fitting solar panels to your home:

• Solar panels
• Battery (if you want one)
• Labour

Solar panels

Globally, the cost of photovoltaic panels is at an all-time low. The cost of solar panels was $0.11 per watt in the US at the end of March 2024 (around half the price a year before), following a sharp rise in Chinese solar panel exports.

In the UK, we haven’t quite seen the same drop in price. This could be partly because demand is low as a result of inconsistent government policy and a 28% rise in installation costs between January 2019 and January 2024.

However, the efficiency of photovoltaic panels increased by 25% between 2010 and 2019. So the amount of electricity generated per £1 spent has increased.

How much will they set you back, exactly? The following cost estimates include installation:

• 1-2 bedroom house: £4,216
• 3 bedroom house: £7,026
• 4 bedroom house: £9,837

Solar panels are typically sold together, rather than individually. This is handy since their total daily output will be advertised, making it easier to find what you need.

For example, if you wanted to generate 5,000 watts of electricity per day you could buy a package of 12 415-watt panels or 16 300-watt panels.

Often, it’s cheaper to buy more lower-watt panels than fewer higher-watt panels. But you’ll need more roof space to fit them.

Battery costs

If you want to store the energy generated by your solar panels, you’ll need to invest in a particular battery.

Solar battery storage systems can cost from under £1,000 to over £10,000 depending on the capacity and brand. So they’re not insignificant purchases. But they offer several benefits:

• Store the energy you generate to prevent wasting ‘free’ solar energy.
• Keep your lights and electrical items running during a power cut.
• Use battery-stored energy during peak times to avoid peak-time electricity costs.
• Store electricity to sell back to the grid at the most cost-efficient times.
• Go off-grid by storing enough energy to use throughout the day.

Home battery systems are a relatively new concept that hasn’t yet been widely adopted. But once it does, costs are likely to fall.

Labour costs

Unless you intend to install the solar panels yourself (which we don’t recommend for safety reasons), you’ll be looking at paying a qualified technician around £150 to £200 per day.

It should take a technician around 2-3 days to install the panels, so the total labour cost could be around £450 to £600.

How long do solar panels take to pay for themselves?

Can you get grants for solar panels?

Solar panels aren’t cheap. But you may be able to receive a grant to help fund the installation, depending on your circumstances.

Grants don’t have to be paid back. And they’re usually provided by the government, local council or a utility provider.

You can check which grants you might be eligible for on our Grants page (you’ll need a Snugg account to access it) or by visiting the gov.uk website.

Are solar panels worth it?

Adding solar panels to your home could be a great long-term investment. But they might not be suitable for everyone.

Environmental benefit

Installing solar panels reduces the amount of energy you need to draw from the grid which, in turn, reduces the carbon emissions produced by your home.

And studies show that a solar panel only needs to generate energy for four years before it’s recovered the same amount of energy and associated pollution that went into manufacturing the panel in the first place.

After that, your solar panel should have a net positive effect on the environment for up to 46 years - unlike a gas boiler which will continue to burn fossil fuels until the end of its lifespan.

Self-sufficiency

It could be worth installing solar panels if you’re looking to decrease your reliance on grid electricity.

Not only will you be less affected by energy prices, but you’ll also minimise the risk of blackouts (so long as you have a solar battery).

The peace of mind that comes with being self-sufficient could be worth the cost alone.

Solar panels for sheds

Solar panels don’t have to be attached to the roof of your home. They can be installed anywhere, including on top of your shed.

If your shed needs power - for lighting or plug sockets, for example - installing solar panels could be worth looking into.

Solar panels could also be a non-disruptive way of powering your shed without having to dig up the garden to bury a power line connected to your house.

It could be relatively affordable, too. Depending on the size of your shed and how you use it, you’ll almost certainly need a smaller setup than if you were to install solar panels on your house.

And hey, if your house is short on suitable roof space - or you simply want more power - then you could always install additional solar panels on your shed to power your house.

Should you get solar panels in Scotland?

Scotland may not be known for its sunny weather, but there’s more than enough sunshine to power solar panels.

In fact, Errol Estate Solar Farm in Perthshire generates enough electricity to power 55,000 homes.

So you can be confident that installing solar panels is worth considering for all the reasons already discussed in this guide.

But there are a couple of differences to note.

Scotland enjoys slightly fewer hours of sunshine than the rest of the UK (1,384 hours per year in Edinburgh vs 1,460 hours in London) so it may take a little longer to recoup the upfront cost of installing solar panels.

And the Scottish government offers its own grant schemes (see below).

What are home energy Scotland grants?

At the time of writing, the Scottish government offers the Home Energy Scotland Loan scheme for those who meet their criteria.

This cashback loan scheme allows you to recoup up to £7,500 (£9,000 for rural households) of the cost of installing solar panels (as well as many other energy efficiency improvements).

You can learn more about Scotland’s energy-saving home improvements grant on the gov.scot website.

Should you get solar panels in Wales?

Wales is one of the sunniest parts of the UK, with Cardiff clocking up 1,553 hours of sunlight per year versus London’s 1,460 hours.

So investing in solar panels is well worth considering for all the reasons already discussed in this guide.

Should you get solar panels in Northern Ireland?

Northern Ireland is one of the least sunny areas of the UK, with Belfast enjoying just 1,285 hours of annual sunshine versus London’s 1,460 hours.

But that’s still more than enough sunlight to make solar panels an effective way of bringing down your energy bills and reducing your home’s carbon emissions.

So investing in solar panels is still worth considering for many of the reasons discussed in this guide.

You can find out if there are any suitable energy efficiency grants in Northern Ireland on the nidirect.gov.uk website.

How do you install home solar panels?

There are two ways to install solar panels; you can do it yourself or hire a technician to do it for you.

We don’t recommend most people attempt to install solar panels themselves since getting onto a roof can be very dangerous and you’ll need to know what you’re doing.

It’s easy enough to find a technician (Snugg can help you find one - enter your postcode to find a local installer) and the process can be done within a day.

Here’s how a technician would install your panels:

1. The roof’s integrity will be checked to see if it’s able to support the panels safely (this is done by a surveyor).
2. Scaffolding will be erected to safely reach and carry the equipment to the roof.
3. Anchor points will be fixed to the roof (usually the rafters below it).
4. Solar panel mounts will be attached to the anchors so that the orientation of the panels can be adjusted.
5. The solar panels will be attached to the mounts and orientated for optimum sun exposure.
6. An inverter will be installed to convert the generated DC power to AC power which can be used around the home (a battery can be installed at this point too if you have one).
7. The solar panels will be wired up to the inverter.
8. The system will be connected to the national grid via your breaker box.

Are solar panels right for my home?

Hopefully, this guide has helped you figure out whether installing solar panels might be right for your home.

But if you’re still not sure, we can help you find out in just a few minutes.

Simply visit Snugg.com and enter your postcode to get a personalised energy efficiency plan.

The plan will show you the potential cost and savings of installing solar panels to your home, along with other energy efficiency installations - like double glazing and heat pumps.

Ultimately, every home is different. But solar panels can be a great way to reduce energy bills, reduce carbon emissions and boost the value of your home.