Solar photovoltaic or PV for short is the method of generating electrical power from the sun. PV installations have grown rapidly in recent years due to the governments FIT (feed in tariff) scheme. A PV installation involves mounting solar panels on either a roof or a spare piece of garden or yard. A solar pv installation does not fall under the domestic RHI scheme.
How PV works?
Solar cells within the solar panels convert the suns radiation into DC electricity. This is then run through an Electrical Inverter which converts the direct current to alternating current to then be used in our homes to power our kettles, televisions and lighting etc.
Types of PV panels
- Mono-crystalline: Solar cells made up of wafer thin slices of silicone crystal. They are the most efficient panels available but also the most expensive and delicate. These types of panels are often found in revolutionary modern buildings as they can be embedded into glass.
- Poly-crystalline: Solar cells that have been made from melted down and re-crystalised silicone. They are less efficient than mono-crystalline panels but are much cheaper. These types of panels can also be embedded into glass. Poly-crystalline panels are the most commonly used in the UK.
- Amorphous (thin film): Extremely durable but offer a much lower efficiency compared to the other types of panel. Amorphous panels are the cheapest on the market but require a lot more space to be as effective as a poly or mono-crystalline array.
Roof space and direction?
Solar PV gives its highest outputs when facing South. Other orientations of panels can be installed but this will have a negative effect on the amount of electricity the panels create per year. Ideally Solar PV systems should be installed at a roof pitch of around 35 degrees to ensure they catch all of the available sunlight during a day and should be installed away from any potential shading such as trees, lamp posts and any inline buildings.
Savings and costs?
A small size solar system would take up around 14 square metres of roof space and would generate around £400 of savings for your home per year. This installation would cost between £3000-£5000.
A medium sized solar system would take up around 28 square metres of roof space and would generate around £800 of savings for your home per year. This installation would cost between £5000-£8000.
A large sized solar system would take up around 42 square metres of roof space and would generate around £1000 of savings for your home per year. This installation would cost between £9000-£12000.