Solar Photovoltaics

Harnessing the energy of the sun is a very attractive approach to meeting our energy needs. There are a range of converter technologies such as solar collectors (for hot water), solar concentrators (for thermal electricity generation) and photovoltaics (PV). PV is an elegant solution, a converter with no moving parts, which is has a long lifetime (25 years + for mono-crystalline silicon) and minimal maintenance burden (dc side of a system). PV may be applied as either a grid connected or off-grid, standalone system. Standalone systems are usually employed in developing countries to provide lighting, refrigeration or power for communication systems. PV is competing with diesel generators in these applications which have high maintenance, fuel and supply costs. Grid connected PV offers the potential for energy generation at the point of use in urban environments or large scale solar plants in solar resource rich locations such as southern Spain and California. In terms of microgeneration in the built environment, the potential energy yield from PV is perhaps the easiest to predict. Roofs and facades offer large areas at suitable inclinations / orientations.

Silicon wafer solar cells have a low working voltage (~0.5 V) and so must be connected electrically in series to become useful. A ‘standard’ PV module consists of 36 cells in series, producing a maximum power point voltage of ~18 V suitable for charging a 12 V dc battery with a charge regulator. Grid connected […]

Background Photovoltaic modules have no moving parts and last upwards of 25 years with no maintenance aside from the occasional cleaning. Realising such a long lifetime for entire PV systems relies on the continued integrity of all system components. The installation of modules in building facades and other structures has necessitated the use of push […]

The Sustainable Energy Research Group has led a programme to develop what is believed to be the world’s first solar powered refrigeration unit installed on a working articulated vehicle for Sainsbury’s Supermarkets Ltd. Power for the refrigeration unit is generated by photovoltaic panels mounted on the trailer’s roof. An on-board battery stores the excess power for use by […]

Capital cost is the major issue and this impacts most directly on the size of a PV roof tile. For the ‘best integration’ a PV roof tile should be indentical in size and weight to a normal concrete tile. For example, a Marley Modern tile would provide an exposed area of 292 x 345 mm […]