Solar Photovoltaic (PV) panels absorb energy from the sun and convert it directly to electrical energy. The amount of electricity produced depends on the area of panels, the intensity of light and the efficiency of the panels. The most common installation involves mounting the panels on a south facing roof in order to maximize the level of sunlight falling over them. Although direct sunlight will produce the greatest amount of electricity, it is not essential and solar panels will usually provide some electricity even on cloudy days.
How it works
In a typical solar cell, silicon absorbs sunlight and produces a flow of electrons (electricity) across it. The cells are then linked together to form a solar panel and the panels can be further linked into modules, giving a wide range of possible voltage output. The electricity produced is Direct Current (DC) which will be converted to Alternating Current (AC) for most applications.
There are three types of solar cell, monocrystalline, polycrystalline and thin film. Each has different electrical properties and typical efficiencies range from ten to twenty percent. Solar panels can be mounted on a roof, integrated with the roof and now there are even solar tiles which will blend with the existing roof tiles. Solar panels can also be mounted on frames on the ground.
There are two options for micro-generation systems; grid-connect and stand-alone. Grid-connect systems consist of the solar panel array and an inverter which converts the DC current into AC current which is harmonized with the National Grid. This allows any surplus electricity to be sold back to the energy provider, in effect using the National Grid as a battery. In stand-alone systems the electricity produced is stored in a bank of batteries.
The area required for solar panels is relatively large. An example installation will cover 10m2 and produce a peak of around 1.5kW. This would cover a third of a typical household electricity requirement.
In a new-build situation or when a roof is being renewed, integrated panels or tiles can replace traditional roofing materials, off-setting some of the cost of the PV.
An Energy Performance Certificate, otherwise known as an EPC, provides an energy rating for a home. As part of our solar PV installation we conduct and EPC inspection to ascertain what band your home falls into.
To qualify for maximum tariff your home needs to qualify for a category D or above once your installation is complete.
Solar energy funding may be available for small or large projects, whether domestic or commercial depending on various factors of eligibility.
If you are thinking of investing in renewable energy systems for your home or business, you can find out more about eligibility at: http://www.energysavingtrust.org.uk