What is a PV Solar Panel?
Solar power, an energy form that involves the harnessing of energy from sunlight, turning it into electricity (also known as the photovoltaic effect) is thought to be one of the cleanest forms of renewable energy available at present. This form of alternative energy has steadily gained momentum over the last decades especially as electricity costs rise, fossil fuel stocks diminish and governments offer incentives to adopt cleaner, greener energy forms. With over 100% year-on-year growth in Photovoltaic (PV) system installation, PV module makers dramatically increased their shipments of solar panels in 2010. Globally, analysts report the largest markets for solar installations are currently Germany, Spain and the US.
In basic terms, Solar Panels are composed of PV cells, silicon-based or as a sprayed surface chemical, all of which are assembled in such a way as to react to light and catalyse the production of electrical energy. Each solar panel only has the ability to generate a certain amount of electricity therefore installations often contain several panels, called a Solar System, though size varies according to the solar panel you choose. There are a three main types of solar panel available - Monocrystalline, Polycrystalline and Thin Film, and it is worth researching them all before choosing which is right for you, especially as prices are becoming ever more reasonable across the market.
Monocrystaline Solar Panels
Solar panels made from monocrystalline silicon cells (single-crystal cells) are highly reliable and have been used for decades. There are suggestions that some units installed in the 1970's are still operational. Monocrystalline panels are, in comparison, more expensive than other available panels and are often used in telecommunications. However, reduced efficiency is experienced above standard conditions and they are effected by elevated temperatures.
Polycrystalline Solar Panels
Reportedly less efficient than monocrystalline solar panels, these semi-conductor, multi-crystal silicon cell panels are cheaper to produce, a benefit that is passed onto consumers. Their make up involves several individual cells packaged together, interlinked and then pinned by metal conductors. Like monocrystalline cells, polycrystalline cells are also effected by high temperatures, with their efficiency reduced considerably (12-15% reduction it is reported).
Thin Film PV Solar Panels
There are two choices of Thin-Film solar panels: Rigid or Flexible. The former is manufactured 'in one-go' on a production line, usually involving a sheet of glass. The latter, flexible Thin-Film solar panels, involves the application of layered photovoltaic chemicals thinly-laminated onto the surface of a conducting material, such as metal. A weather-protecting sealant is administered on the top surface to preserve the unit. Each layer of PV chemical applied will react to different types of light. Therefore, both forms of this particular PV solar panel is more likely to respond to low light from cloudy days for example – perfect for locations with reduced sunlight. Makers claim costs are kept to a minimum because of favourable construction overheads in comparison to that of semiconductor silicon panels (no expensive silicon cells to mount and interlink), and the increased efficiency thanks to the length of daylight hours the panels will work.