Daylight lands on the photovoltaic module and is converted to clean electricity. An inverter then converts the electricity from direct (DC) to alternating current (AC), for use in the home. At certain times the solar energy system could be producing more power than is needed and this is exported back to the national grid. At night and during periods of high electricity usage, electricity that you need is bought from the national grid in the normal way.

Yes! The cells in the PV system only require daylight to work and will even generate energy on cloudy days. It is also thought that becuase of the pitch that a roof in this country is built, your system could be catching as much daylight as other countries on the continent.

There is no simple answer, and it will depend on a number of factors:

A - How much money you would like to invest?

The supply and installation of a system can cost approximately of £5,000 per kWp and you should allow approximately 8 square meters of surface area per kWp. An average system size would be 2kWp and the maximum size under the feed-in tariff is 4kWp.

B - How much of your electricity you want to generate?

For most households, systems between 1.5 & 3 kWp, that will generate between 1300 & 2500 kilo Watt hours (kWh) of electricity per annum are most commonly fitted, but remember, you also get paid for any excess electricity that you generate.

C - How many panels can be installed in an optimal location?

Your system will be designed to suit the location, space and budget available for the project. The cost of installation will also vary according to how easy or difficult it is to access the roof and the type of fixing that is required.

The feed-in tariff rates are currently set at 41.3p for every unit (kWh) of electricity you generate, regardless of whether you use it or not. Any electricity that you generate and subsequently use will save you 9-12p per unit where you don’t have to buy it from your normal supplier. You will also receive an additional 3p for every unit exported back to the grid that you generate surplus to the requirements of your home.

Most estimations benefit from a payback term of approximately 10 years or so, leaving you to carry on earning a further 15 years of cash back from the feed-in tariff. The feed-in tariff payments are guaranteed for 25 years regardless of the intial cost of your system. The added benefit of free electricity for years to come after your payback period and the feed-in tariff are also key points to remember. Most importantly, the feed-in tariff payments are index linked to inflation which will help to offset the expected rise in fuel costs – the sooner you act the greater the benefit would be.

On domestic properties the maximum size system that can be installed and qualify for the highest Feed in Tariff of 41.3p is a 4 kWp array (approximately 29 square metres surface area and roughly 20 panels). Installations above this size are classed as commercial and the tariff is reduced slightly.

No, PV systems are designed to be installed by qualified Solar PV installers and electricians, accredited to MCS standards (Microgeneration Certification Scheme). Only qualified installers are able to process, organise and commsission your connection to the Government Feed In Tariffs Scheme (FITS).

Solar PV modules can be cleaned in the same way as standard building glazing but in general, PV systems are self-monitoring and operate automatically with minimal maintenance.