The most common solar PV installation in UK homes is a 3.5kWp system, capable of generating approximately 3,000kWh of electricity each year in optimal conditions. This amounts to around 75% of a typical household's electricity consumption, meaning that a solar system can make a home largely self-sufficient, dramatically. A large portion of potential solar panel earnings comes from the government's generation tariff, which is part of the Feed-In Tariff (FIT) scheme. Under the generation part of this. On top of the generation tariff, you also receive a fixed rate of 4.5p/kWh for any surplus electricity that you feed back into the National Grid. This rate is subject to change, but if you join the FIT scheme before April 2013 then it. It's important to remember that all the solar PV earnings you make must be offset against the cost of installing and maintaining your solar.