![]() ![]() ![]() Solar energy
Solar
energy Not all the energy radiated by the Sun
reaches the surface of the Earth: some of it is reflected back into space, some is
dispersed and diffused in all directions by air molecules and dust particles in the
atmosphere, and some is absorbed by water vapour, by carbon
dioxide
The simplest and most promising use
of solar radiation in energy terms is that of solar panels, both for heating and for
the direct production of electric
energy At present
there is an enormous number of applications with small
photovoltaic
devices It is worth noting that other renewable sources of energy,
such as
hydroelectric Solar energy produces heat which can be exploited in many practical applications: flat panels for producing hot water, heating greenhouses, etc. Fig. 2 shows some applications of
photovoltaic solar panels - used for weather applications (top left), to
supply a building with electric energy (bottom left) and for public lighting (right), using
batteries Apart from the normal photovoltaic systems,
there are also
thermoelectric solar systems In many countries, numerous programmes and various incentives have been approved with regard to the direct use of solar energy with flat photovoltaic panels: Germany has a "100000 solar roofs" programme and in Italy, as already mentioned, ENEA is running a similar project. The United States of America has a programme for one million solar roofs, in part thermal solar, and Japan has a similar programme. The European Community also has a similar programme which includes aid for developing countries. |