Spanish company TSK has designed the first optical system to inspect parabolic trough collectors at solar thermal plants in order to spot any defects that might affect their ability to generate power. The system is more precise than conventional inspection solutions.

Parabolic trough concentrated solar power (CSP) technology is the most widely used of the four technologies that exist today to take advantage of solar energy. This system begins by concentrating the Sun’s rays using a line of curved mirrors toward an absorption tube. Within this tube a fluid circulates that later transports the heat energy produced to a storage area and conversion into electricity.

In order to improve the efficiency of these parabolic trough collectors and the solar energy power plants where they are used, it’s important to monitor their geometry as closely as possible and find any possible defects in the reflective mirrors.

TSK has created the first extensive optical system that can find possible manufacturing and positioning defects in these collectors. The conventional methods used today are very time consuming and normally only test 4-5% of the collectors in a plant, which leaves a lot of room for error.

The system developed by TSK is based on the workings of the CSP systems themselves, but in reverse. A mobile laser is placed at the point of the conduction tube for the heat-conducting fluid, and from there a beam is sent toward the mirror.

The system takes pictures of how the laser hits the mirror, and these images are analyzed by a software program that looks for any possible deformations in the trough. This cuts the inspection time to less than one minute per collector and enables inspecting their entire surface, thus guaranteeing that the collectors are in perfect condition when they are placed into service.

TSK has also been involved along with Spanish companies Sener and Acciona in the installation of Morocco’s first large solar thermal plant at Ouarzazate near the Sahara desert, as well as the solar facility at Bokpoort in South Africa by the Kalahari desert.