Photovoltaics is concerned with the direct conversion of (sun)light into electricity by means of solar cells. The silicon solar cells generate direct current as soon as the sunlight hits the cell surface. As this happens without requiring any movable parts or chemical processes, the solar cells have extremely long lifecycles of well over 30 years. A number of individual solar cells are connected electrically and framed to form weatherproof solar modules. In a solar power system, these modules can be connected to any desired number of strings. This allows both small low-power installations as well as high-wattage solar systems to be implemented.

Most solar power systems are grid-connected, whereas so-called off-grid or stand-alone solutions make up only a minor percentage of the photovoltaic systems installed in Europe. These are used in allotment gardens, for example, or as autonomous power supply systems without access to the utility grid, such as traffic information systems or cottages and campers.

To maximize the power output, the solar modules should face towards the south and be mounted at a tilt angle of between 25° and 30°. Steeper module tilt angles, e.g. up to 60°, will reduce the output by about 10%. The energy output of the solar modules is also reduced when the system faces towards the south-west or south-east. Orientation towards the east or west still provides a minimum output of about 15 to 20%. Since the output reduction is limited, the use of a solar system thus makes sense even if the module location and orientation is not ideal. However, orientation towards the north (NE, NW, N) is not suitable for solar power systems.

An additional benefit of photovoltaic systems is the significant reduction of CO₂ emissions. Even a rather small system with a total power of only 3 kWp (which is equivalent to a roof size of about 27 sq.m.) eliminates CO₂ emissions in the region of 10 to 15 kg per day, which would otherwise be produced by less eco-friendly power systems such as coal power stations, combined heating and power stations or gas turbine power stations.

PV-traker 5kWp power