Posted on 01 June 2004
Solar energy: Immense potential
Solar energy in the stricter sense (1) can be used in three ways:
· Solar thermal collectors use the solar radiation falling on them to heat tap water (and, to a lesser extent, to heat water for space heating).
· Photovoltaic modules convert solar radiation directly into electricity.
· Solar thermal power plants use solar heat by concentrating solar radiation (for instance using mirrors focussed upon a “solar power tower”, or by means of parabolic troughs) and then conveying the energy of the medium thus heated to a turbine or to a Stirling engine. 
The sun also drives our climate – wind, clouds and thus also rain are a result of solar irradiance. Similarly, sunshine is essential to biomass. This is why wind energy, hydropower and biomass are included under the concept of solar energy in a wider sense.