What Is Solar PV?

What Is Solar PV?

Solar Photovoltaic (or solar PV for short) systems work by capturing the sun’s rays using photovoltaic cells.

PV cells are thin layers of semi-conducting material (usually silicon). Electrical charges are generated when the silicon is exposed to light, which can be conducted away as direct current. The stronger the sunshine, the more electricity is produced (you will still generate electricity on a cloudy or dull day, but you will generate more if it’s sunny).

Multiple cells are connected together (usually behind glass) to form a photovoltaic solar panel. PV solar panels come in a variety of shapes, sizes and come in either black or blue (depends upon the crystalline structure of the PV cells). The choice depends on where you intend to put them.

Where to put the PV?
Typically solar PV panels will be placed on the roof of your house. They can either be integrated into the roof, replacing some tiles, or fixed on top of the existing roof tiles.

A pitched roof is the best site for a PV solar system. South-facing roofs give the best result, but East or West facing roofs are also fine. You will need to check that the panels are not shaded by high buildings or trees, as this will reduce their efficiency.

One other thing you will need to check is the strength of your roof. Solar Photovoltaic panels are not light, particularly when they are placed on top of existing tiles. Your solar PV installers should check the strength of the roof structure before advising you on the best system – but do remember to ask.

How much do they cost?
How much the PV solar panels cost will depend on the type (whether integrated or on-top) and how many you are installing. Remember that the photovoltaic solar panels cost is only one part of the project: you are likely to need scaffolding as well as experienced installers to do the job properly.  

The most cost-effective time to install solar photovoltaic panels is when you are having your roof replaced, as the extra cost of the solar pv installation will be minimal. Under the Government’s Feed-In Tariff scheme, you can be paid for the electricity you generate, and for the surplus electricity you export to the grid.  (see the section on The Feed In Tariff for more information).