thermodynamic solar energy.
Mechanical or thermodynamic solar refers to devices that transform solar radiation (heat) "directly" into mechanical motion that can be used directly or transformed into electricity.
Solar mechanics is a rare and very special technique. Each "solar engine" has unique, if not unique, characteristics. It is therefore very difficult, unlike the two other uses of solar, to present a principle of operation. A single common point: the concentration of solar energy via solar concentrators (heliostats, mirrors ...). We will return to these techniques in a future article.
To apply this technique, so we will mention three practical examples: the Solar Stirling engine, the Wheel of Minto and solar thermal power plants (actually: thermodynamic would be a better term) producing electricity.
All these projects and engines still remain fairly marginal. A higher cost of fossil fuels could boost R & D such solar applications.
Three examples of mechanical solar installations.
a) solar Stirling engine:
The famous hot-air engine with the heat source is the sun. For more information about her, click here
b) The wheel of Minto:
Project of an independent inventor who has never seen the industrially day yet the idea seems good.
c) Solar power (solar or electric): these are the most successful mechanical solar projects.
A solar thermal power plant consists of a field of solar collectors special called heliostats that concentrate sunlight on a pipe through which a heat transfer which drives a turbine that produces electricity.
The largest solar thermal power plant is called Solar Two, is located in California's electric power reaches 150 megawatts (150 000 kW!).
There 2 Examples of such plants in France: the solar plant Vignola (Corse-du-Sud) or solar power Themis (Pyrenees).
The history of Themis(About Jean Jacques BEZIAN Doctor Engineer in Physics of Energy and Research Professor of the Center for Energy and the Ecole des Mines de Paris)
THEMIS solar power plant was built on the site of Targasonne, and it produced its last kilowatt hour the 30 September 1986!
The unique French trial production of electricity using a solar tower, the THEMIS adventure took place in three stages:
- a preparatory phase to 1975 1979 around a joint team EDF - CNRS;
- a construction phase of 1979 1983 to, under the authority of EDF (the equipment Region Alps Marseille, REAM;
- an exploitation phase, from June to September 1983 1986, the Regional Group of Thermal Production (GRPT) Mediterranean.
It was during this period that three experimental teams, one of the Studies and Research Department (ERD) of EDF, based in Chatou, near Paris, a second in the premises of the Ecole Centrale in paris, attached to the CNRS, the last on the site, the Scientific Assessment Panel THEMIS (STRP mixed team AFME - CNRS) analyzed the performance obtained and proposed innovative concepts for future commercial power plants.
Since then, nothing (in solar applications), but campaigns astrophysical measurements, and a few thousand visitors a year to this modern but still vestige of French hopes to develop a solar thermal electric sector.