Please note PV systems generate electricity and are not to be confused with Solar Thermal or solar water systems that are used to heat water.
What is solar electricity?
Solar electricity is the same as your regular mains supply but because it's generated from sun light its clean, silent and from an inexhaustible supply…
“The sun delivers enough solar energy to earth in 15 minutes to supply the whole world with energy for year.”
PV* or photovoltaic modules convert light into dc electricity. An inverter changes the dc electricity into ac electricity so that we can use it in our homes for cooking and lighting etc. *The correct technical term for this process is Photovoltaic - or PV for short.
The simplest and most cost effective systems consist of a number of PV modules mounted on the roof or onto a frame on the ground.
What is a Photovoltaic module?
PV modules are made up of specially coated Silicon cells. As light falls on these cells electrons rush from one side of the silicon to the other and an electrical current is created. The more cells there are the more current is generated. When the right number of modules are linked together enough voltage is created to match the system voltage with the mains or grid.
Module type & performance:
Poly Crystalline PV modules rated at 1 kWp will generate approximately 750-850kWh per annum in the UK climate*, provided the array is south facing and un-shaded.
Poly Crystalline modules are the most commonly used. Poly Crystalline means that the silicon cells are cut from a block made from many pieces of silicon. They have a blue-flecked appearance. Most manufacturers offer Poly Crystalline modules.
Mono Crystalline PV modules rated at 1 kWp will generate approximately 850kWh per annum *E.g. Sharp 180 watt modules.
Mono Crystalline modules usually have a white diamond shape between the cells. Mono Crystalline means the silicon cells are cut from a single block of silicon.
Hybrid PV modules rated at 1 kWp will generate over 900kWh per annum. E.g. Sanyo HIP modules
Hybrid modules comprise a mono crystalline cell with a thin amorphous layer - they are up to 12% more efficient. They have the highest power to area ratio on the market so they are an obvious choice for roofs where space is at a premium.
The ideal site will be within 40 degrees of south. The Ideal pitch is around 30 degrees
Sites that face 90 degrees from south will suffer a 20-30% reduction in performance.
Diagram
Click to enlarge the diagram
*These figures are based on experience of previous installations and are not a guarantee of how much energy a given system will yield in a given year.
How the PV system works
The electricity generated by the PV modules is converted from DC to AC by an inverter and connected to your consumer unit. The electricity flows to wherever it is needed to power your appliances. At times when there is more electricity being generated than is needed - it will flow out through an export meter into the grid to be used locally by your neighbours. The meter records the exported electricity and the exported units can be sold to a number of electricity supply companies.
See Sell your electricity back.
The “clean” solar electricity is always used in priority over electricity from the grid. When the solar panels can't generate sufficient electricity - at night, for example - electricity is drawn from the grid in the normal way, so you will never be without electricity.
Solar electricity is the same as your regular mains supply but because it's generated from sun light its clean, silent and from an inexhaustible supply…
“The sun delivers enough solar energy to earth in 15 minutes to supply the whole world with energy for year.”
PV* or photovoltaic modules convert light into dc electricity. An inverter changes the dc electricity into ac electricity so that we can use it in our homes for cooking and lighting etc. *The correct technical term for this process is Photovoltaic - or PV for short.
The simplest and most cost effective systems consist of a number of PV modules mounted on the roof or onto a frame on the ground.
What is a Photovoltaic module?
PV modules are made up of specially coated Silicon cells. As light falls on these cells electrons rush from one side of the silicon to the other and an electrical current is created. The more cells there are the more current is generated. When the right number of modules are linked together enough voltage is created to match the system voltage with the mains or grid.
Module type & performance:
Poly Crystalline PV modules rated at 1 kWp will generate approximately 750-850kWh per annum in the UK climate*, provided the array is south facing and un-shaded.
Poly Crystalline modules are the most commonly used. Poly Crystalline means that the silicon cells are cut from a block made from many pieces of silicon. They have a blue-flecked appearance. Most manufacturers offer Poly Crystalline modules.
Mono Crystalline PV modules rated at 1 kWp will generate approximately 850kWh per annum *E.g. Sharp 180 watt modules.
Mono Crystalline modules usually have a white diamond shape between the cells. Mono Crystalline means the silicon cells are cut from a single block of silicon.
Hybrid PV modules rated at 1 kWp will generate over 900kWh per annum. E.g. Sanyo HIP modules
Hybrid modules comprise a mono crystalline cell with a thin amorphous layer - they are up to 12% more efficient. They have the highest power to area ratio on the market so they are an obvious choice for roofs where space is at a premium.
The ideal site will be within 40 degrees of south. The Ideal pitch is around 30 degrees Sites that face 90 degrees from south will suffer a 20-30% reduction in performance.
Diagram
Click to enlarge the diagram
*These figures are based on experience of previous installations and are not a guarantee of how much energy a given system will yield in a given year.
How the PV system works
The electricity generated by the PV modules is converted from DC to AC by an inverter and connected to your consumer unit. The electricity flows to wherever it is needed to power your appliances. At times when there is more electricity being generated than is needed - it will flow out through an export meter into the grid to be used locally by your neighbours. The meter records the exported electricity and the exported units can be sold to a number of electricity supply companies.
See Sell your electricity back.
The “clean” solar electricity is always used in priority over electricity from the grid. When the solar panels can't generate sufficient electricity - at night, for example - electricity is drawn from the grid in the normal way, so you will never be without electricity.
