Solar Panels (PV)

Generate electricity from sunlight

Solar panel electricity systems, also known as solar 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.

Key benefits: of solar electricity

  • PV panels provide your own clean power source that helps reduce global warming. A typical home solar PV system could save over a tonne of carbon dioxide per year – that's more than 30 tonnes over its lifetime.
  • Reduce your electricity bills, since daylight is free.
  • Installing them may also increase the value of your property.
  • Are extremely low maintenance.
  • Have a long lifetime of 25 years or more.
  • Are silent in operation and can be visually unobtrusive.
  • Increases your awareness of electricity use and encourages more energy efficient behaviour.
  • Improves your home’s energy efficiency rating

How do solar panels (PV) cells work?

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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 direct sunshine, the more electricity is produced.

Costs, savings and maintenance

Costs

The average domestic solar PV system is 3.5kWp and costs around £7,600 (including VAT at 5%).

Costs have fallen significantly over the last year. They vary between installers and products, so we recommend a hand full of local mcs approved installers we have worked with closely over the last few years.

For a list of recommended installers please email us paul@acornelec.co.uk

Savings

A 3.5kWp system can generate around 3,000 kilowatt hours of electricity a year – about three quarters of a typical household's electricity needs. It will save over a tonne of carbon dioxide every year.

If your system is eligible for the Feed-In Tariff scheme it could generate savings and income of around £635 a year (based on a 3.5kWp solar PV system eligible for a generation tariff of 15.44p/kWh correct as of 28/11/12 ).

You will get paid for both the electricity you generate and use, and what you don't use and export to the grid. When applying for FITs you will need to show evidence of your property's Energy Performance Certificate and this will affect what tariff you can get. If you would like us to recommend someone for the ECP please email us paul@acornelec.co.uk

Please note that the Feed-in Tariff scheme is not available in Northern Ireland.

´╗┐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 additional benefit of being cleaned by rainfall to ensure optimal performance. Debris is more likely to accumulate if you have ground mounted panels.

If dust, debris, snow or bird droppings are a problem they should be removed with warm water (and perhaps some washing-up liquid or something similar – your installer can advise) and a brush or a high pressure hose (or telescopic cleaning pole) if the panels are difficult to reach. Always be careful if you are working above the ground or near the top of a ladder. Alternatively, there are a number of specialist window cleaning companies who will clean solar PV panels for you at a cost (of around £30 based on our research in March 2012) depending on the size of your array and location. Many of these companies use a water fed pole system which does away with the need for a ladder.

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 may need replacing some time during this period. Consult with your installer for exact maintenance requirements before you commit to installing a solar PV system.