Carmelo natale solar energy

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Liceo Statale Vito CapialbiVibo Valentia, ItalyComenius Project

NO HUMAN NO CRYHeadmaster: Mr Giovanni PolicaroProject Coordinator: Anna Pia Perri

by Carmelo Natale I A MVienna, 14-18 March 2012

Solar Energy

The Sun is an extremely powerful energy source, and solar radiation is by far the

largest source of energy that reaches Earth, but when it hits the Earth’s surface this energy

is quite low intensity. This is partly because the Earth’s

atmosphere and the clouds absorb nearly 54% of all

incoming sunlight.

In the 20th century, solar energy became increasingly attractive as an energy source because, unlike fossil

fuels such as coal, oil and natural gas, reserves a virtually inexhaustible and it

does not pollute.

It is easy to convert solar energy into heat (thermal energy) using

flat-plate collectors. Solar panels are mainly used for heating water

and homes.

Solar radiation can be converted directly into electricity photovoltaic cells. In these cells, a

small electrical voltage is generated when light

strikes the junction between a metal and a semiconductor (such

as silicon).

The voltage generated by a single photovoltaic cell generates only a very low

voltage which is why, so far, they have mainly been used for low-power

applications, for examples calculators and watches.

However, if large numbers of individual cells are connected together, more than one kilowatt of electric power can be generated but these larger units are very

expensive and so far they have been used only to provide power for weather and communication

satellites.

The potential for solar energy is enormous; unfortunately the current high cost of collecting, converting and storing it has made it less attractive as an exploitable energy source.

We can find other kinds of photovoltaic cells also in Calabria, particularly in

coastal and sunny areas.We can find other kinds of photovoltaic cells also in Calabria, particularly in coastal and sunny areas.