Commercial parabolic trough CSP plants: Research trends and technological advancements

Solar energy is an auspicious renewal energy source because of its abundant availability and its flexibility to be converted into heat or into electricity. Concentrated solar power technologies are promising units for producing electricity in large scale applications and parabolic trough solar collector is the most matured technology for these plants. The objective of this paper is to summarize and to discuss the current status of parabolic trough collector commercial power plants around the world and the technological developments in various constituents of such concentrated solar power plants. More specifically, this review includes various developments in the concentrators and receiver tubes in order to enhance both the thermal and the optical efficiencies. Moreover, the different existing and newly developed heat transfer fluids are discussed in this work and the emphasis is given in the discussion of the different operating temperature levels, the storage system and the applications that use different fluids. Furthermore, different tracking options of the parabolic trough solar collector are examined, different storage technologies, as well as various power cycles and their modifications to enhance the overall efficiency of the parabolic trough collector-based power plants are discussed in detail. The final conclusions of this work indicate the recent developments and the future designs of the parabolic trough solar collector power plants.