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Parabolic Trough Technology Research and Development

Parabolic trough R&D efforts focus on improving the technology's performance and cost competitiveness.

Learn more about these efforts, including parabolic trough technology R&D today, the organizations involved in research and development, and its R&D history.

R&D History

Since Luz built the first commercial parabolic trough power plant in 1984 (SEGS I), parabolic trough technology has been constantly evolving and improving. Luz made significant progress during the seven year period when the nine SEGS (solar electric generating station) plants were built. Following 1991, the operators of the SEGS plants, government research laboratories, and industry continued to develop the technology.

R&D Today

The parabolic trough technology of today has significantly improved from the last SEGS plant built 15 years ago. However, substantial opportunities remain for further improvement in efficiency, improvement in component reliability, or reduction in cost.

R&D efforts focus on all aspects of parabolic trough solar power plant technology.

Solar Field

The research and development of parabolic trough collector technology has focused on the following:

  • Receiver — Development of improved more reliable receiver designs with improved selective coatings, and able to operate at higher temperatures
  • Concentrator Structure — Development of lower cost structures that maintain the optical performance of LS-2 collector.
  • Reflectors — Lower cost and higher performance reflectors that are more durable, with improved solar reflectivity, and that reduce mirror washing requirements.
  • Balance of Collector Systems — Improved drives, controls, and collector interconnects.

Thermal Energy Storage and Heat Transfer Fluid

R&D activities have focused on development of the indirect two-tank, molten-salt thermal energy storage (TES) option for near-term applications. The longer-term R&D efforts focus on new storage or process designs that could substantially reduce the cost of parabolic trough technology, including moving to a higher temperature heat transfer fluid (HTF), or direct steam generation in the solar field.

Other advanced thermal energy storage options include advanced heat transfer fluids in a single-tank thermocline storage system, concrete thermal energy storage, or phase-change thermal energy storage.

Power Plant Technologies

R&D activities have focused on the best approaches to integrate parabolic trough technology into combined-cycle power plants, how to optimize the design of parabolic trough plants utilizing an organic Rankine cycle, and how to minimize the impact of dry cooling. Additionally, some work has focused on how to reduce the O&M costs of solar power plants.

Systems Integration

One of the key R&D efforts has been to develop the tools and testing capabilities to characterize the performance of the various parabolic trough components. Additionally many new models have been developed for evaluating systems or specific components.

R&D Organizations

The U.S. Department of Energy Solar Technologies Program administers its research and development of parabolic trough technology through SunLab — a partnership between NREL and Sandia National Laboratories.

Other organizations involved in parabolic trough research and development include:

For more information, see our list of publications on parabolic trough research and development.