The MS trough is a new kind of parabolic trough collector, which in comparison to other parabolic trough collectors offers special features for the operation with molten salt as heat transfer medium.
An important advantage of the MS trough is that it makes nightly solar field heating for preventing salt solidification dispensable – the molten salt is drained and pumped to a well isolated storage tank during night. In the next morning, the absorber tubes are pre-heated by solar irradiation and afterwards refilled with hot molten salt.
The MS trough is constructed in such way that the line of gravity in the concentrator as well as the rotation axis of the collector are located in the absorber tube axis (the focal line). Because of this, the absorber tube is not rotating while tracking the sun and the concentrator is turning around the “stationary” absorber tube (fixed focus).
Meanwhile, the absorber tube is completely detached from the concentrator by a new kind of bearing. This allows very large thermal expansions of the absorber tube. Therefore, the MS trough reaches a collector length of over one kilometer with an almost continuously irradiated absorber tube.