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Solar panels

Generate cheap, green electricity from sunlight

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What are solar panels?

Solar panel electricity systems, also known as photovoltaics (PV), capture the sun's energy using photovoltaic cells.

These cells don't need direct sunlight to work – they can still generate some electricity on a cloudy day.

The cells convert the sunlight into electricity, which can be used to run household appliances and lighting.

The benefits of solar electricity

  • Cut your electricity bills. Sunlight is free, so once you've paid for the initial installation, your electricity costs will be reduced.
  • Cut your carbon footprint. Solar electricity is green renewable energy and doesn't release any harmful carbon dioxide or other pollutants. A typical home solar PV system could save around 1.3 to 1.6 tonnes of carbon per year (depending where you are within the UK).

How do solar panels (PV) cells work?

PV cells are made from layers of semi-conducting material, usually silicon.

When light shines on the cell it creates an electric field across the layers. The stronger the sunshine, the more electricity is produced.

Groups of cells are mounted together in panels or modules that can either be mounted on your roof or on the ground.

The power of a PV cell is measured in kilowatts peak (kWp). That's the rate at which it generates energy at peak performance in full direct sunlight during the summer.

PV cells come in a variety of shapes and sizes.

Most PV systems are made up of panels that fit on top of an existing roof, but you can also fit solar tiles.

Solar tiles and slates

Solar tiles are designed to be used in place of ordinary roof tiles.

A system made up of solar tiles will typically cost about twice as much as an equivalent panel system.

Solar tile systems are not normally as cost-effective as panel systems, and are usually only considered where panels are not considered appropriate for aesthetic or planning reasons.

How much could solar panels save me?

Costs, savings and financial support for solar

England, Scotland and Wales

A 4kWp system can generate around 4,200 kilowatt hours of electricity a year in the south of England – that's the same amount of electricity as it takes to turn the London Eye 56 times. It will save around 1.6 tonnes of carbon dioxide every year. A 4kWp system in Scotland can generate about 3,400 kilowatt hours of electricity a year – that’s the same amount of electricity as it takes to turn the Falkirk Wheel 2,200 times. It will save approximately 1.3 tonnes of carbon dioxide every year.

The average domestic solar PV system is 4kWp and costs around £6,200  (including VAT at 5 per cent). 

The table below shows how much money you could save on your electricity bills by using the energy you generate. This depends on your lifestyle - the more you are at home during the day, the more you are likely to save. Look at the column which most suits the times of day that your home is occupied. 

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Location

Savings on bills (£/year) last updated April 2019

Home all day

Home in the mornings

Home in the afternoons

Out all day until 4pm 

Out all day until 6pm

London, South England £240 £195 £175 £120 £100
Aberystwyth, Wales £230 £185 £170 £120 £95
Manchester, North England £230 £185 £165 £115 £95
Stirling, Scotland £220 £175 £160 £110 £90

Solar panels were eligible for Feed-In Tariff payments. The FITs scheme closed to new applications on 31 March 2019. If you have already installed solar PV with a MCS certificate dated on or before 31 March 2019 you may still be able to apply. For more information about the FITs scheme and recent changes please visit our Feed-In Tariffs  page.

Northern Ireland

The table below shows how much money you could save on your electricity bills by using the energy you generate. This depends on your lifestyle - the more you are at home during the day, the more you are likely to save. Look at the column which most suits the times of day that your home is occupied. 

Location

Savings on bills (£/year) last updated April 2019

Home all day

Home in the mornings

Home in the afternoons

Out all day until 4pm 

Out all day until 6pm

Belfast, Northern Ireland £260 £205 £185 £130 £105

Please note, the Northern Ireland Renewables Obligation Certificates (NIROCs) scheme is now closed to all technologies since April 2017 and you can’t receive payments from generation tariffs any more. However, you can still cut your electricity bills by using the free electricity generated by solar PV and receive export payments from the electricity excess that you sell to the grid.

The table below shows you how much you'd be likely to receive in export payments per year, depending on the amount of time you are at home. Figures are based on a standard three-bedroom terraced house.

Location

 Export tariff (£/year) last updated April 2019

Home all day

Home in the mornings

Home in the afternoons

Out all day until 4pm 

Out all day until 6pm

Northern Ireland £126 £142 £148 £166

£173

 

Costs can vary between installers and products, so we recommend getting quotes from at least three installers. 

Other factors that affect PV installation costs are:

  • The more electricity the system can generate, the more it costs but the more it could save.
  • Larger systems are usually more cost-effective than smaller systems (up to 4kWp).
  • PV panels are all about the same price per kWp, but PV tiles cost much more than a typical system made up of panels.
  • Panels built into a roof are more expensive than those that sit on top.

 

 

Solar PV maintenance

Solar PV needs little maintenance – you'll just need to keep the panels relatively clean and make sure trees don't begin to overshadow them.

In the UK panels that are tilted at 15° or more have the benefit of being cleaned by rainfall to ensure optimal performance. Debris is more likely to accumulate if you have ground mounted panels.

Once fitted, your installer should leave written details of any maintenance checks that you should carry out from time to time to ensure everything is working properly. This should include details of the main inverter fault signals and key trouble-shooting guidance. Ideally your installer should demonstrate this to you at the point of handover.

Keeping a close eye on your system and the amount of electricity it’s generating (alongside the weather conditions) will familiarise you with what to expect and alert you to when something might be wrong.

The panels should last 25 years or more, but the inverter is likely to need replacing some time during this period, at a cost of about £800.

Consult with your installer for exact maintenance requirements before you commit to installing a solar PV system.

Helpful resources

 

Solar Energy Calculator

Use the Solar Energy Calculator to gain an idea as to what financial benefits you may see from installing a solar PV system.

Try our tool

Financial support

Find out what support is available for renewable technology specifically in Scotland.

Discover more

Speak with an expert

For independent advice on solar technology, contact your local energy advice centre.

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