/SOLAR THERMAL TECHNOLOGY
What is solar thermal energy and how is it generated?
Solar thermal energy is a renewable energy source that converts the heat from solar rays into electricity by indirect means, using steam cycles.
Three kinds of technology are used to generate solar thermal power: parabolic trough collectors, tower-like collectors or dish collectors. Currently, the first technology is considered the most promising.
Parabolic trough collectors are mirrors that reflect solar rays on a large scale and focus them on a central heating or receiver tube running the length of the parabolic trough at its focal point. Solar thermal power stations using parabolic trough collectors are suitable for operation within an average temperature range from 125º C to 400º C.
The mirrors constantly track the movement of the sun across the sky, ensuring that the heating potential is exploited to the maximum. The mirrors reflect the solar radiation onto the central heating tube, consisting of a primary circuit containing a fluid (water, oil or other). This fluid can reach a temperature in the region of 425º C.
The heat absorbed by the fluid in this way is transferred to a secondary circuit of water, transforming it into steam. This steam then drives the turbine and, consequently, the attached generator.