Cut your carbon footprint: solar electricity is green, renewable energy and does not release any harmful carbon dioxide (CO2) or other pollutants. A typical home photovoltaic (PV) system could save around 1200 kg of CO2 per year - that's around 30 tonnes over its lifetime.
Cut your electricity bills: sunlight is free, so once you have paid for the initial installation your electricity costs will be greatly reduced. A typical home PV system can produce around 40 percent of the electricity a household uses in a year.
Sell electricity back to the Grid: if your system is producing more electricity than you need, or when you cannot use it, someone else can use it - and you could make a bit of money. Read more about feed-in tariffs and selling electricity.
Store electricity for a cloudy day: if your home is not connected to the national grid you can store excess electricity in batteries to use when you need it.
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What is PV and how does it work?
Solar PV systems capture the sun's energy using photovoltaic (PV) cells. The cells convert the sunlight into electricity, which can be fed back into the national grid by an inverter, and attract the new "feed-in tariff". PV cells do not need direct sunlight to work - you can still generate some electricity on a cloudy day.
What is the feed-in tariff for solar PV?
The feed-in tariff for solar PV is 41.3 pence. Plus a further 3p per kWh for any surplus which is fed back into the National Grid.
Who pays me for the feed-in tariff?
Your energy supplier pays you for producing clean energy either monthly or quarterly.
How long will the feed-in tariffs last?
Solar PV is the longest tariff at 25 years guaranteed the feed-in tariff will be reviewed in 2013 and every 5 years after that.
How do photovoltaic (PV) cells work?
PV cells are panels you can attach to your roof or walls. Each cell is made from one or two layers of semiconducting material, usually silicon protected by glass. When light shines on the cell it creates an electric field across the layers. The stronger the sunshine, the more electricity produced.
Does the glass front reflect the sun away?
The solar panels are designed with an anti-reflective coating which increases the amount of sun absorbed in to the solar cells.
What do PV panels look like?
PV cells come in a variety of shapes and colours, from grey "solar tiles" that look like roof tiles to panels and transparent cells that you can use on conservatories and glass.
What is KWp?
The strength of a PV cell is measured in kilowatt peak (kWp). That is the amount of energy the cell generates in full sunlight. Solar radiation of 1KWp per square meter is used to define standard conditions. In the UK, one kilowatt peak of solar will generate roughly 850 kilowatt hours (kWh) per year.
What is KWh?
A kilowatt hour is 1000 watts. This same as a unit of energy on your electricity bill.
Is solar PV suitable for my home?
To tell if solar electricity is right for you, there are a few key questions to consider:
Do you need planning permission?
In England and Scotland, you do not need planning permission for most home solar electricity systems, as long as they're below a certain size. You should check with your local planning officer if your home is a listed building, or is in a conservation area or World Heritage Site.
Do you have a sunny place to put it?
You'll need a roof or wall that faces within 90 degrees of south, and isn't overshadowed by trees or buildings. If the surface is in shadow for parts of the day, your system will generate less energy.
We have trees close to the roof; will it affect the efficiency of the system?
In some instances the trees can be cut so the panels receive more sun but without an onsite survey it is impossible to be more accurate about the potential performance of the system.
Is my roof strong enough?
Our installers will perform a site survey and make an assessment; normally the basic structural survey carried out by the installer is sufficient.
What is the correct pitch of the roof?
30-40 degrees from horizontal is best.
What direction does my house need to be?
The best direction is south facing. East-west is possible but the system will be less efficient.
How much roof space is needed?
Depending on the technology used either panels or tiles, roughly 7 square meters is needed per KWh.
If I do not have enough space can I split up the panels?
Yes this is possible. The installer can advise you the best layout for multiple locations.
How are the panels fixed?
There are various ways in which the panels can be fixed, the ‘on roof’ system uses a mixture of hooks and brackets or the ‘in roof’ system replaces existing tiles. Both systems will not damage the roof.
Can I use solar tiles?
Solar tiles cost more than conventional panels but if you need major roof repairs, PV tiles can offset the cost of roof tiles.
Can they be attached to anything else apart from the roof?
They can be boarded on to an A frame to the correct angle and placed on any flat surface. Mounted vertically on a south facing wall but will lose 30%of the optimum.
How much does it cost?
The costs of installing a solar PV system can vary it can depend on location, how easy it is to access the roof and technologies used. A typical installation will costs between £5000-£6000 per KWp, with an average system is between 2-3 KWp.
Will the cost and installation become cheaper?
The panels and technology are not likely to become any cheaper but the feed-in tariff are at the highest now so it’s the best time to invest.
How long will it take a PV system to pay back the cost of installation?
An average system roughly takes 8 to 12 years to pay for itself, after this period it will continue to make money for the rest of its life. For example, if you spend £10,000 you would receive roughly 9 percent of your investment back per annum.
What is the average size of PV system?
The majority of people install a system between 2-3 KWp, which will generate between 1700-2500KWh per annum.
What is the largest system that I can install?
4 KWp which needs 28 square meters of roof space.
How much can I save?
Savings can be considerable - almost 1 tonne of CO2 a year, and around £200 off your electricity bill. A 2 kWp system could provide around 40 percent of a household's yearly electricity needs.
After installing PV panels can I be self sufficient?
This is possible if batteries are used but these are not environmentally friendly. If batteries are not used then no.
How long do the PV panels last?
The panels have a manufacturer’s warranty of 25 years, but as there are no moving parts there is no reason why they will not last for longer.
What maintenance costs are there?
As there are no moving parts, maintenance is at a minimum the panels can get dirty but varied weather conditions generally keep them clean.
