Types of Mounted PV Panels

Solar PV (photovoltaic) panels are used to change the sun's energy into electricity which can be used to power the electric appliances in the home or business. Most panels are roof mounted to receive maximum sun hours. However, it is possible to ground mount PV panels. There are several main types of roof mounted PV panels. They three types are monocrystalline, polycrystalline, and thin film. They are all constructed using a semi conductor, typically silicone. Monocrystalline panels are made from a single silicone crystal. Monocrystalline are the most efficient, but also the most expensive. Polycrystalline are the second most efficient type of panel, and are slightly cheaper. Polycrystalline panels are made from a block of silicone, The least efficient type of PV panel are thin film panels. These are made from atoms of semiconductor material on a metal or glass base. The efficiency rate range from seven percent for thin film to fifteen percent for monocrystalline panels.

Hybrid Panels

A new entrant to the market is the hybrid panel which provides electricity and heat. Producing heat improves the efficiency of these panels by between twenty to forty percent. Additionally hybrid panels require less space than a separate thermal and a PV system. Hybrid panels are the most efficient of all roof mounted panels, but they are also the most expensive.

Costs of Roof Mounted PV Panels

The cost of a roof mounted PV panel system depends upon the type of panel chosen, the nature of the building's roof, and the size or power of the system. Comparison sites exist on the Internet to compare companies costs. A typical domestic system of 4kw will typically cost £14,000 upwards Whereas a 2.5 kw system will cost perhaps closer to £11,000. An exact quote can only be given once an installation company has inspected your property and carried out a survey on the roof to ascertain if it is strong enough to hold roof mounted panels. The roof must be able to hold not only the weight of the panels, but also upward forces generated by the wind under the panels. If strengthening is required then this, typically costs several hundred pounds. Most solar panels come with a twenty five year warranty and require minimal maintenance.

Feed In Tariffs

When considering the cost of installing PV panels feed in tariffs may be a consideration. If a domestic system up to 5kw is installed by a company approved by the MCS scheme, then the householder will be eligible for cash back. The cash back is a government scheme to encourage take up of new technology. It pays 43.3p per kilowatt hour the system generates and is guaranteed for twenty five years. The income is dependent on the size and efficiency of the PV panels. Estimates of income are in the region of £900 to £1,100 per year. This income is free from tax. Some companies will install PV panels for free. In this arrangement, the householder benefits from free or cheaper electricity whilst the installation company benefits from the feed in tariffs. The installation company will typically be responsible for the installation costs and maintaining the panels post installation.