Guide to home solar panels

What are solar panels?

There are two main types of solar power available for your home. They may look similar, but they’re very different in terms of what they do.

• Electricity-generating solar panels – known as photovoltaics (PVs), take energy from the sun and convert it into electricity. These panels give you electricity that you can potentially sell to the grid.

• Water-heating solar panels – known as solar thermal systems, use the sun to heat your water. The water flows through coils in the panels and back into your water cylinder. The panels don’t generate electricity, so it’s only your household that can benefit from reduced running costs.

Why is solar power so important?

Did you know that the sun radiates more energy down to the earth’s surface in one day than the whole planet will use in a year? Imagine every home being able to tap into that energy, without the need for a power grid to make and distribute energy all over the country.

Our sun is an amazing source of renewable energy, and an ever-increasing number of UK homes are installing solar panels to take advantage of it. According to provisional government figures, for the end of December 2023 there was a total of 15.7 GW of solar capacity in the UK across 1,441,285 installations. This is an increase of 6.9% (1.0 GW) since December 2022.

Domestic installations, such as panels on the roof, account for 29% of the total capacity. Solar farms make up about 50% of capacity.

What are the benefits of solar panels?

There are many benefits of solar power, including:

• A lower electricity bill – depending on how much electricity you use and the size of your PV panels, you may be able to produce enough energy for your whole home. If you opt for a solar thermal system, you should also save money on heating water.

• Money-making potential – you can sell your unused electricity from your PV system to the grid. Someone else can use it, and you’ll make some extra cash as a result.

• A lower carbon footprint – solar energy is renewable, so you’re powering your home without burning fossil fuels – saving the planet one bit at a time.

• Increase the value of your property – an energy-efficient home could be more valuable and attractive to potential buyers because it has the benefit of reduced energy bills.

• Year-round electricity – despite common misconceptions, solar panels still work on cloudy days and even during winter.

How much do solar panels cost?

The average PV system size provides around 3.5kWp of electricity and costs around £7,000 according to the Energy Saving Trust.

When you get a quote make sure it includes the cost of the inverter, which is needed to convert the direct current (DC) power produced by the panels to alternating current (AC) need to run household appliances.

If you are re-roofing your property you could consider solar tiles, but these might work out more expensive than panels.

The costs of your home PV system will vary depending on what type of solar option you go for, how much power you need and the cost of labour to install. They’ll also vary per provider, so it’s worth comparing a few quotes to make sure you get the right deal for you.

The cost of installing a typical solar water heating system is around £6,000. Costs will depend on whether you choose evacuated tube or flat-plate collectors, as well as the size of the system and whether you need to replace your boiler and include a larger hot water cylinder.

While the initial outlay is high for either system, you need to weigh that up against the potential savings over the lifetime of the panels – or for the period you’re likely to be in the house.

Sunlight is free, so once you’ve factored in buying the panels and paying for installation, you can expect to see substantial savings on your bills, even if you have to supplement your usage with some electricity from the grid. Given the current energy prices, it’s a good time to start making your own electricity if you can. Not to mention the environmental benefits and cutting your carbon footprint too.

Will solar panels work for my home?

To work out if solar panels would be a good fit for your home, you’ll need to determine if your roof is suitable and how effective you home solar panels will be. Consider the following factors:

• Your home’s orientation – the more sunlight your panels get during the day, the more effective they’ll be. A south-facing roof is the best spot for a solar power system and north facing is not recommended. East and west-facing systems will yield less power than south-facing panels. Take advice from an expert if needed.

• The angle of your roof – to be at their most effective, your home solar panels will need to face the sun at a certain angle. Your potential supplier should be able to tell you if your roof is suitable.

• Is your roof strong enough for the system you need? A typical installation will take up around 20m² roof area, according to the Energy Saving Trust. If your roof isn’t big enough, you may have to go for a smaller system.

• Is your roof big enough? For example, to produce 4kW of electricity, you’ll need 16 x 250W panels. Each 250W panel typically measures 1.6m² so your roof will need to be over 25.6 m² to accommodate them all. If your roof isn’t big enough, you may have to go for a smaller system.

• Will your panels be in direct sunlight or shade? Are there any trees, buildings or other structures throwing shade onto your roof that could stop your solar panels getting the sunlight they need?

How much can you make from PV solar panels?

Making money from your PV panels isn’t guaranteed, and it could take many years to recoup the purchase and installation costs. You’ll need to factor in the original installation cost, any cost savings on your electricity bills and how much you earn for any energy you sell to the grid. But as panels come down in price, the time to break even is getting shorter.

There are many variables that can affect the payback/profitability outcome. For example, using household appliances during the day when your solar panels are generating free power for you.

Even the placement of your solar panels can affect the amount of energy produced. Depending on the size of your PV system and whether you have any solar storage in place, you may still need to rely on the grid for some of your electricity use.

On the other hand, if you end up making more electricity than you need, you can sell your surplus electricity back to the grid under the government’s Smart Export Guarantee (SEG) scheme. Under the scheme, the larger electricity suppliers pay small-scale electricity generators for the clean electricity they provide to the grid. The tariffs are decided by the energy suppliers so it’s worth shopping around to find the best rate for you.

The SEG scheme was brought in to replace the previous Feed-in-Tariff scheme, which closed to most new applicants in April 2019.

Can I get a grant for solar panels?

Unfortunately, the government no longer offers grants to help pay for solar panel installation in England, Wales and Northern Ireland. If you live in Scotland, you could apply to Home Energy Scotland for a grant or interest-free loan for solar panels and other kinds of renewable energy, depending on your eligibility.

You might be able to get a grant from the Energy Company Obligation Scheme administered by the energy companies or schemes administered by your local authority. These are typically aimed at people on certain benefits or for low-income households that live in energy-inefficient homes.

For households not eligible for this kind of grant, one potential way of bringing down the cost of solar panels is to use a group purchase scheme.

Groups of people wanting to install solar can get together, then installers bid for the work. The size and the bargaining power of the group can help keep prices down. Some councils round the country participate in this type of Solar Together schemes. Estimates of potential savings are between 10-25% depending on the scheme.

To encourage energy saving, VAT on the installation of energy-efficient home improvements such as solar panels has been cut from 5% to zero from 1 May 2023 until 31 March 2027. This should help reduce the costs of installing your home solar power system.

Are solar panels effective in the UK?

The UK isn’t exactly known for its sunny weather, but that doesn’t mean we can’t benefit from solar energy.

Although PV panels do work more efficiently on sunny days, they don’t need direct sunlight to work. They can still generate electricity on cloudy days, and in some ways, they might be better suited to cooler temperatures, because there’s less of a risk of them overheating. Having said that PV has a very low (0.05%) failure rate.

How to compare solar panels

When you’re comparing solar panel systems, the first thing you’ll need to know is how much electricity you need. Find out your current electricity consumption – measured in kilowatt-hours (kWh) – and decide how much of that you can and want to cover. Look at the amount of available and suitable space you have on your roof and the number of sunshine hours available to see what is possible.

Here are some points you should consider when comparing solar panel options:

• How much power a panel can provide (measured in watts).

• The efficiency of the panel, meaning how much sunlight can be converted into electricity (measured as a percentage). As well as looking at their current efficiency, it’s also a good idea to check their efficiency level for say 25 years or the warranty period (if that’s longer).

• How the panel’s performance is affected by temperature.

• The size of panels compared to your available space.

• The weight of panels and whether that works with your roof.

• The product warranty – this can be up to 40 years, but read the terms carefully to see what exactly is covered.

• How much the panel’s performance will decrease over time.

• Installation costs – if these are separate.

• If you’re going to include a battery in your system.

• The price and your budget.

How much power you use of what you generate will be affected by various factors. These include whether you work from home, charge an electric vehicle, how you heat your water and how much you run your appliances during the day.

When it comes to comparing options, it’s important to remember that the cheapest option isn’t always the best. You want to make sure that your solar panels have a good lifespan. You’ll also need to weigh up the panel’s efficiency versus the cost.

When it comes to PV panels, you have three main options:

• Monocrystalline solar panels are made of one piece of silicon. You can recognise them by their sleek, black appearance. They’re the most effective and space-efficient and but also the most expensive.

• Polycrystalline solar panels are made from several pieces of silicon and they have a blueish colour. They’re easier to produce and therefore cheaper, but they’re less efficient.

• Thin-film solar panels are the cheapest to make and buy because they require less material and they can be made from various materials such as silicon, cadmium, and copper. They’re more flexible and they’re tolerant to heat, but they’re the least efficient model on this list.

There are also solar roof tiles available for those who don’t like the appearance of solar panels, but these are considerably more expensive.

As solar technology improves, new types of panels become available so always check what your options are.