Question:

At the beginning of the 1980s, we often heard about the “Thémis” solar power plant in the Pyrenees, one of the first of its kind. However, the cost of the electricity generated by the plant was too high and it was shut down shortly afterwards. Renewable energies are once again on the agenda, particularly solar energy. Would it make sense to reopen “Thémis”?

Answer:

The solar power plant built in Targassonne in the eastern Pyrenees was indeed shut down in 1986 after only three years of operation. Some of the mirrors were converted into reflectors and used until 2004 to study gamma rays from space. The local administration of that region, which owns the site, and a subsidiary of the engineering firm Tecsol restored the plant to its original use and it generated its first kilowatt-hours on October 25. The thermodynamic process used initially was abandoned, however. That process was based on the use of a series of mirrors which concentrated the suns rays at the top of a 100-meter tower, where they heated a fluid to activate the generators. Today, sunlight is collected by photovoltaic cells and converted directly into electricity. The plant now consists of four panels measuring 50 square meters each, for a total capacity of 30 kW. When completed, the plant will include 80 heliostats for a total capacity of 600 kW, which is still rather limited.