A renewable generator, such as PV Solar, can be connected to the national grid in most countries. Also, when a solar PV array is connected to the grid you get paid for producing solar energy. With the system of FIT payments, a good income can be earned from even small (2-4KW) PV systems...
It works like this: Light from the sun (either directly or through thin clouds) hits the solar panels and is converted into DC electricity. With grid-connected systems the DC electricity is fed, via two small cables and an isolating switch, to a special inverter. This compact and quiet DNO approved inverter transforms the DC electricity into an exact replica of the AC grid-electricity and sends electrical power to the house circuits and back to the national grid (if there is surplus). An electricity meter measures how much solar electricity is being generated so that it can be sold (for around 15p/unit (KWh).
Typically, in Southern UK, 4 KW of PV panels (8m x 3.5m) will generate about 4,000KWh (units) of solar electricity per year - a 2KW system will produce half...
Typical costs (through SUSTAINERGY) are from of £1,200 per KW including installation. A typical 4KW system is around £5,500 installed.
Most roofs are suitable, providing they face between East, South, and West - optimum pitch is between 20-60 degrees. Roof material is not a problem - the PV array is secured (with 125mph loading tests) to special aluminium rails that are screwed to the roofs rafters through the slate/tile/shingle/concrete etc. Strict attention is paid to continuity of weatherproofing. Alternatively the whole array can be integrated into the roof - like a Velux roof window.
The whole PV system has a basic 2 year warranty, with 10 year full guarantee on the mounting structure, and the PV modules 25 years! The system has a life expectancy of over 35 years... Maintenance on PV systems (unlike WIND systems) is absolutely minimal - gentle washing of the PV glass and possible inverter service.
SUSTAINERGY are MCS accredited installers and thus have passed a strict quality control criteria. Local councils also contract us to install on remote public buildings.