Photovoltaic systems



In years to come, there will not be a single, unique source of electricity, but many renewable (and non renewable) electricity sources that will be combined to answer the planetís electricity needs. Photovoltaic energy and wind energy are likely to become the dominant form of electricity generation in the future.

With solar cells, it is possible to convert sunlight directly into electricity by the photovoltaic process. As sunlight is uniformly distributed, this enables every building to have the potential to generate solar electricity locally. The roof is the most convenient place to mount the solar cells if it is correctly orientated to receive solar irradiation.

The potential for generating electricity directly from sunlight is very large and is becoming increasingly cost effective as the technology improves and the price of electricity generated by conventional sources like fossil fuels increases.


  • The technology can be used almost anywhere since sunlight is available everywhere.
  • The production equipment can almost always be installed close to the consumption site, thereby avoiding electricity losses during distribution and transport.
  • The installation size can be easily adjusted according to needs and available resources.
  • There is no operational pollution. No gaseous discharge, no waste, no risk of physical accidents.
  • There is very little maintenance or repairs as there are no moving parts.
  • Electricity can be produced locally, encouraging energy sobriety to balance energy produced and energy consumed.


  • The roof of the building has to be correctly orientated i.e. south facing
  • The technology is currently expensive but costs are steadily decreasing

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