LINE-FOCUS CONCENTRATING SOLAR THERMAL TECHNOLOGIES UNIT

Silicone Fluid Maintenance and Operation (SIMON)


Participants: DLR (Coordinator), CIEMAT-PSA, Wacker Chemie AG, TSK Flagsol Engineering, Innogy, Rioglass Solar Sch, Senior Flexonics, TÜV NORD
Funding: Solar.ERA-NET; Spanish Ministry of Economy, Industry and Competitiveness (Programa RETOS - Acciones de Programación Conjunta Internacional 2017); German Federal Ministry for Economic Affairs and Energy (BMWi).
Reference: PCIN-2017-009 (Spain)
Duration: October 2017 – September 2019
Background:
The use of thermal or synthetic oil in solar power plants with parabolic-trough collectors (PTCs) is commercially extended. The silicone-based heat transfer fluids present an attractive functionality and applicability to heat transfer fluid based on diphenyl/biphenyl mixtures, whose use is extended in current power plants in operation. The feasibility of a silicone oil formulation, HELISOL® 5A from Wacker Chemie AG, has been demonstrated in the previous SITEF project.
Objectives:
The SIMON project (Silicone Fluid Maintenance and Operation) aims to demonstrate the applicability of two products of the HELISOL® range, which have improved viscosity and lower vapor pressure, thus facilitating a substitution scenario for the heat transfer fluid currently used in solar power plants with parabolic troughs in operation. This demonstration of the use of these fluids with operating temperatures of 425 °C in the PROMETEO and REPA testing facilities of the Plataforma Solar de Almería, will be completed with the study of the behavior of improved PTCs’ components for the new test conditions, in particular receiver tubes, by Rioglass Solar, and flexible joins for the interconnection of collectors, by Senior Flexonics. Finally, we want to demonstrate a reconditioning / recycling process associated with a resistance of 25 years of thermal properties of the fluids that will be intensively tested during the project.
Public results:

  • Press release on the achieved proof of concept and the successful release test of HELISOL at Plataforma Solar de Almería: https://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10258/368_read-29176/#/gallery/31564 
  • C. Hilgert, C. Jung, G. Saliou, J. Dersch, C. Wasserfuhr, J. León. Status report on silicone based heat transfer fluids for CSP. In Proceedings of the ASME 2018 Power and Energy Conference, Lake Buena Vista (USA), 24-28.06.2018. Ref. 2018-7769. ISBN 978-079185141-8.  
  • E. Schaffer, C. Hilgert, C. Jung, C. Wasserfuhr, J. León, L. Valenzuela. Silicone based HTF in parabolic trough applicatons – from lab to loop. SolarPACES Conference 2018, Marrakech (Morocco), 03.10.2018.
  • L. Valenzuela, E. Schaffer, C. Hilgert, C. Jung, G. Saliou, J. León. Novel silicone HTF for parabolic troughs power plants: Operational experience at PSA (Spain). CSP Focus Innovation 2018, Xi’an (China), 26.10.2018.
  • C. Hilgert, C. Jung, C. Waserfuhr, J. León, L. Valenzuela. Qualification of Silicone Based HTF for Parabolic Trough Collector Applications. SolarPACES 2018. AIP Conference Proceedings 2126, 080003 (2019). https://doi.org/10.1063/1.5117598