Silicone Fluid Test Facility (SITEF)

Participants: DLR (Coordinador),CIEMAT-PSA, Wacker Chemie AG, TSK Flagsol Engineering, Senior Flexonics, TÜV NORD, Innogy, Rioglass Solar.

Financed by: Solar.ERA-NET; Spanish Ministry of Economy and Competitiveness (Programa RETOS - Acciones de Programación Conjunta Internacional 2014); German Ministry of Innovation, Science and Research of the North-Westfalia region (MIWF NRW).

Reference: PCIN-2014-083 (Spain)

Duration: January 2015 – December 2016/2017

The use of thermal or synthetic oil in solar power plants with parabolic-trough collectors (PTCs) is commercially extended. Currently the widely used type of heat transfer fluids are eutectic mixtures of diphenyl oxide and biphenyl, which have limitations on the maximum operating temperature, 395°C, and also at the minimum operating temperature for solar field pumping. The silicone fluids are an alternative; these fluids are used in installations of small and medium scale but are currently much more expensive and present similar maximum operating temperature limitation of diphenyl/biphenyl mixtures.

The SITEF (Silicone fluid Test Facility) project aims to demonstrate the loop scale functionality and applicability of a new silicone heat transfer fluid (SHTF) named HELISOL® developed by Wacker Chemie AG, and associated PTC components at temperatures up to 450°C. Such operation temperatures are beyond state of the art in PTC power plants and increase the overall power plant efficiency.

This innovative project will be achieved in a German-Spanish cooperation making use of the so called PROMETEO test facility at Plataforma Solar de Almería (PSA). This facility is being modified to install new components in the solar field that will allow continued operation under real operating conditions with fluid temperatures above 400°C. During the development of the project is planned to reach at least 1000 h of operation above this temperature level.