Project: High performance parabolic trough collector and innovative silicone fluid for CSP power plants

Acronym Si-CO (Reference Number: ID14)
Duration 01/04/2021 - 30/09/2023
Project Topic The Si-CO project aims to techno-economically demonstrate a new optimized and large-scale parabolic trough collector (Si-PTC) design that operates using HELISOL® XLP at 430ºC, a silicone-based heat transfer fluid (Si-HTF). This project also pursues to demonstrate and evaluate the exchange of this Si-HTF in existing power plants. The combination proposed (Si-PTC + Si-HTF), enables a cost reduction in the solar field, HTF and TES CAPEX of 12% and a 14% in OPEX for new solar plants. The technology proposed will enhance the annual energy production of a commercial PTC plant by 7.5% and the global capacity factor by 2%. Altogether, this translates in a LCOE reduction of up to 15%. Furthermore, the exchange application of the Si-HTF in existing plants, designed for an operation T of 400°C, has the potential to fix the H2 permeation issues because HELISOL® XLP shows almost zero formation at 400°C. After the HTF exchange, the use of HELISOL® XLP will avoid any future H2-HCE issues increasing its performance while prolonging its service time and reducing power plant down time, presenting clear O&M and environmental advantages for existing plants even if they can’t operate at 430°C. This also applies to new power plants with higher working T. Therefore, Si-CO pursues the 2 independent actions above mentioned, both based on the new HELISOL® XLP, which has additional cost reduction and better performance potential with respect to the other 2 commercial existing HELISOL® XLPgrades, because it has a lower vapour pressure during operation and can be operated at 430°C. The Si-CO project stands in a row with three international demonstration projects (SING, SITEF, SIMON) that successfully established Si-HTF as a very promising alternative with respect to the state-of-the-art HTF.
Project Results
(after finalisation)
CONTRIBUTION TO THE REDUCTION IN THE COST OF CSP POWER Si-CO project is an innovative solution that aims directly at cost reduction of PTC with silicone oil technology. The impact of Si-CO technologies on OPEX and CAPEX was calculated based on the Acciona Business Performance Model for a 50 MWe PTC power plant with 9 hours of TES . The new PTC using HELISOL®XLP will allow to reduce the CAPEX in Solar Field, HTF and TES systems by 12% (16M€ out of 140M€) and OPEX costs by 14% savings of 0.7M€/year out of 4.8M€. Taking into account all cost reduction, this project will directly affect the cost, increasing the performance and the reliability of CSP plants, leading to a reduction in LCOE of 15%. ENVIRONMENTAL AND SOCIAL IMPACT Si-CO project will bring significant environmental benefits: • Lower environmental footprint of the new HTF (HELISOL®XLP). • New Si-HTF does not contain or form carcinogenic products when aging. • Reduce the life cycle environmental impact of CSP installations by o Increasing the conversion efficiency using improved components o Reducing the solar field size for a given nominal installed capacity to save land.
Call 1st CSP Joint Call

Project partner

Number Name Role Country
1 ACCIONA INDUSTRIAL S.A. Coordinator Spain
2 Deutsches Zentrum für Luft- und Raumfahrt e.V. Partner Germany
3 WACKER Chemie AG Partner Germany
4 Rioglass Solar Systems LTD. Partner Israel
6 Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas Partner Spain
7 Rioglass Solar SCH S.L. Partner Spain
8 Senior Flexonics GmbH Partner Germany