Nowadays the most used energy resources are the so called “not renewables” and, in particular, fossil fuels like oil, cock and natural gas or nuclear fuel like uranium. The availability of these resources is, at present, rather high and consequently their cost relatively low. Nevertheless, reserves are not endless and therefore, considering the actual worldwide energy consumption and his growing trend, it will get serious concerns about both their future availability and their market price in the next years.
The solar energy is the energy associated to the solar radiation and is the primary resources of the planet.
The solar energy is a renewable energy source and can be exploited to produce work that is energy useful for the humanity.
The main technologies capable to convert solar energy in useful energy are:
1. Thermic solar panels
The thermic solar panels (technical denomination is solar collector) are devices that provides for converting the solar energy in thermic energy and for its transferring towards a thermal accumulator for further usage: hot water production, environment heating and solar cooling.
The thermic solar panels must not be confused with photovoltaic solar panels which are applied to produce electric power.
2. Concentration solar panels
The concentration solar panels are devices capable to concentrate sunbeams towards a small receiver through a system of reflecting mirrors.
The thermal energy emitted by the sunbeams concentration is then used to heat a thermal vector liquid, producing steam force, thus electric energy. The concentration systems are also known as Concentrating Solar Power (CSP).
3. Photovoltaic solar panel
These panels are based on the typical characteristic of some semi-conductor to convert the incident solar energy in electric energy. The typical characteristics of the panel (power, voltage, output current) are obtained by a direct sun exposition of the panel with a typical irradiation of 1000 Watt/sqm, at 25°C of temperature in perpendicular position with respect to the sunbeams in total lack of shadows.