The solar power glossary

O Off-grid solar power systems which are not connected to an electricity network. The electricity produced is consumed or stored directly on site (so-called stand-alone systems).
  On-grid solar power systems which are connected to a regional electricity grid. When a large amount of electricity is produced due to optimum levels of sunlight, electricity is fed into the grid; electricity can be drawn from the grid if necessary (when it is dark).
P Photovoltaics refers to the method of directly converting solar radiation into electrical energy.
  Plus sorting all modules achieve an output greater than their specified nominal output (according to performance test). This guarantees optimum efficiency in the system without the need to sort modules.
  Profitability a solar power system's profitability is calculated based on the system's costs, feed-in tariffs and solar incidence at its location. On average, a south-facing system with a roof pitch of 30° pays for itself over 12 to 14 years.
  PV systems short for photovoltaic systems or solar power systems.
R Recycling return of used materials to the economic cycle and their processing into new products. The advantages lie in the reduction of the amount of waste and the conservation of raw materials.
  Renewable energies energies which come from a natural, non-depletable source, such as the sun, water, wind, geothermal heat und biomass.
  Rooftop installation in this type of installation, supporting structures are installed above the roof covering and solar modules are fastened on top.
S Secondary silicon recycled silicon
  Self-generated electricity self-generated electricity can be consumed on site with any remaining power fed into the public grid. In both cases, the feed-in rate for solar electricity is guaranteed by the German state for twenty years under the German Renewable Energy Law. The more electricity is consumed on site, the greater the revenue achieved from the solar power system concerned. The proportion of electricity used on site can be increased to over 60% using intelligent consumption management products. Those who produce self-generated electricity are unaffected by increases in electricity prices. Pressure is also taken off the German grid, as solar power generation and consumption are synchronised directly in the building where the power is used.
  Solar-grade silicon refers to silicon crystals which have a sufficiently high grade of purity to be used in photovoltaic applications. The chemical element silicon is a semi-conductor and forms crystals with a resistant diamond structure. It is the second most common element in the earth's crust after oxygen. For processing in the solar sector, raw silicon is purified to achieve solar-grade silicon and then cast into blocks for further processing into wafers.
  Solar power system complete system of solar panels which produces a direct current thanks to the photovoltaic effect. An inverter converts the generated electricity into alternative current, so it can be fed into the grid.
  Solar panel laminates unframed photovoltaic modules which are embedded in the supporting structure using EPDM rubber strips.
  SolarWorld No.1 racing car specially manufactured by SolarWorld AG in cooperation with Bochum University of Applied Sciences which is powered exclusively by solar energy. The vehicle is driven by a highly efficient solar power generator and reaches speeds of up to 120 km/h. You can find further information about SolarWorld No.1 at
  Solar cell see 'cell'
  Solar2World the 'Solar2World' programme is where the SolarWorld Group brings together all its social commitment projects for the use of solar energy technology, especially in developing countries.
  Stand-alone system solar power systems which are not connected to an electricity network. The energy produced can be stored in batteries ready for use at a later stage.
  STC (standard test conditions) standard test conditions are conditions under which a module or cell's electric and voltage characteristics are measured and then entered on the module data sheet. STC = 1,000 W/m², 25° C cell temperature, solar spectrum AM = 1.5.
  Sunmodule Plus  Sunmodule Plus is an innovative module concept. Plus sorting means that each module achieves a greater output than their specified nominal output (according to performance test), thus guaranteeing optimum efficiency in systems without the need to sort modules.
  Sustainability 1. the capacity to endure; refers to a system which lasts a long time; 2. scientific concept regarding objective limits to exploiting the environment; 3. ethical-normative concept, the core of which is the issue of fairness and balance.
  Sustainability management management of environmental, social and economic factors, firstly, in order to achieve sustainable company and business development and, secondly, to ensure a company makes a positive contribution to the sustainable development of society as a whole.
V Value chain, solar the solar value chain refers to the production stages from sand or raw silicon processing through to the finished photovoltaic module, including recycling.
W Wafer extremely thin discs made of solar-grade silicon used to make solar cells. They can be monocrystalline or multicrystalline.
  Watt international unit of power named after the Scottish inventor James Watt; symbol: W.