Electricity from solar energy – Photovoltaics
The theoretical foundations for Photovoltaics were laid by Albert Einstein, who, in 1921, was awarded his only Nobel Prize for his explanation of „the photoelectric effect“. In very simple terms, Einstein described how light can cause the electrons in certain metals to „move“.
Within a Photovoltaic system, this generates a current within the semi-conductor (mainly silicon) through the movement of electrons and electricity is produced.
Silicon exists everywhere but is a valuable raw material
Silicon is the second most abundant element on Earth after oxygen. Sand, quartz or semi-precious stones like amethyst or opals consist essentially of silicon. Photovoltaic systems require high quality silicon. Although worldwide there are only very few manufacturers of the silicon wafers required (thin wafers of almost pure silicon), production capacities are increasing all the time. Silicon has a decisive social advantage in that unlike oil, sand is available in limitless quantities everywhere, thereby avoiding damage to or conflicts with the environment.
Just a few components assure the electricity supply:
To supply 230V AC on demand in a domestic dwelling, only a few components are required:
- Roof-mounted photovoltaic modules for generating DC current
- An inverter for converting direct current into 230V AC
If the electricity is to be fed into the public grid, an export meter is required to allow the local electricity supply company to deduct the value of this electricity from your bill – that is all.
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