Advice on Solar Photovoltaics (Solar PV)
Solar PV Electricity Panels
Turn light from the sun into cheap, affordable electricity.
Solar PV is the most popular renewable energy technology in the UK, as it has proven to work in the UK climate and it has become a lot more affordable over the last ten years, due to the in the cost of materials and installation.
IS YOUR PROPERTY SUITABLE FOR SOLAR PV?
Solar Photovoltaics (generally just called solar PV) generate electricity during daylight hours by using the suns energy. They don’t need bright sunshine to work and in fact are designed to work even in cloudy British weather.
Most properties with a roof that is approximately South facing are suitable for the installation of solar PV panels. Properties with an East-West facing roof may also be suitable especially if a split inverter is used. However, we would not advise installing solar PV panels on a North facing roof as it is unlikely to receive a lot of sunlight, especially in the winter months when the arc of the sun is lower.
The panels will produce the most electricity if the pitch of the roof is between 30 to 40 degrees. However, PV panels can be installed on most roof types and are commonly installed on flat roofs, using a frame mounting system.
For older properties, the roof timbers would need to be inspected to ensure that they are strong enough to support the weight of the panels; and if the property is a listed building or located in a conservation area then planning permission would need to be sought.
HOW DO THE SOLAR PV PANELS WORK?
Each solar PV panel is made of a number cells containing silicon crystals either as one sheet (mono-crystalline) or many small crystals (poly-crystalline).
As light shines on the cells an electric field is created, causing electrons to flow across the layers of silicon creating electricity.
The panels generate direct current (DC) which needs to be converted to alternating current (AC – or mains equivalent) electricity for use in your home. This is the job of the inverter, which is essentially the ‘brains’ of the system.
The system will automatically export any unused electricity to the National Grid and import electricity when the panels are not creating enough (for example at night). In effect the National Grid is used as a battery.
Energy storage systems, also known as batteries or thermal stores, allow you to capture heat or electricity when it is readily available (ie during daylight hours) and save it until a time when it is useful (ie during night-time).
Electricity batteries help you make the most of renewable electricity and have proven to be very popular with owners of renewable energy systems. There are a number of companies who produce batteries to be used with renewable energy systems, with the most well known company being Tesla. The cost of electricity batteries is dependent upon the size of the batteries and the manufacturer, but is normally ranges from £4,000 to £6,000 for a fully integrated 4kWh system.
Heat batteries can store spare heat or electricity generated by renewable energy systems. They are generally smaller and lighter than thermal stores, and it is claimed that they don’t lose performance over time compared with electrical batteries. However, they are not as widely used as Electricity batteries.
GOVERNMENT INCENTIVE TO INSTALL SOLAR PV
The Government introduced an incentive scheme called the Feed in Tariff (FiT) in 2010 to encourage homeowners to invest in renewable energy technologies such as Solar PV. The Government scrapped the Feed in Tariff in 2019 and it has since been replaced by the Smart Export Guarantee