Costes and Income
The size of the roof will determine the possibilities for the size of the Photovoltaic Installation plant. The more roof space available the more energy can be produced, the more CO2 can be saved and the more money can be made.
For a PV system with a rated power of 1000 watts (1kWp) you will need approximately 10m roof space.
The Energy yield of the UK is expected to be in between 900 kWh for example in Scotland to 1300kWh in parts of Cornwall for such a 1 kWp system.
Already a 2kWp system then produces approximately 2200 kWh of solar electricity in London per annum. This system would generate an Income of around 941.60 plus a Saving of approximately 110.00.