Project: Characterization and Optimization of High Reflectivity Mirrors for Solar Towers

Acronym	MIRAGE (Reference Number: ID12)
Duration	01/03/2023 - 28/02/2026
Project Topic	In this project, it is aimed at maximizing the reflectivity and lifespan of reflective surfaces (termed mirrors in this proposal) for both beam down central receiver applications and heliostats. To achieve this goal, the relationship between mechanical properties, wetting properties, and optical properties will be studied methodically. Mirrors obtained from Sisecam (industrial partner) will be tested in both laboratory environment through accelerated aging tests and through simulation of normal operation conditions achieved by exposing the mirrors to the atmosphere on outside racks in different locations in order to subject the mirrors to environmental loads. These mirrors will be investigated regarding their optical and mechanical properties before the start of each measurement using characterization techniques such as UV-Vis spectroscopy, AFM, and SEM. Initial defects on the protective transparent surface (glass) and the reflective coating will be identified for further testing. Mirrors that are tested outside will be unmounted and tested 1) every three months, 2) after extreme weather events such as thunderstorms to determine the degradation of optical performance and the mechanical problem (defect propagation etc.) responsible for it. Mirrors will further be tested inside a laboratory environment to determine their durability using accelerated aging, high solar flux testing, and corrosion experiments to determine the conditions that result in performance degradation. Data obtained will be analyzed and the mirrors will be optimized for maximum reflectivity, maximum lifespan and minimum cost. Furthermore, the collected weather data will be used to build a simple numerical model to estimate the optical performance at any given location on earth. The outcomes of this study will shed light onto the relationship between mechanical properties and optical properties for the design of mirrors and offer design priorities for the next generation of cost-effective reflective surfaces.
Project Results (after finalisation)	Considering all the economic and environmental benefits alongside the potential to yield high thermal efficiencies, this research proposal has great potential to contribute to the SET-Plan of the European Union. The approach is aimed at reducing the costs of the operation, aligned with the second priority action (reduce costs of technologies). Furthermore, these mirrors could be utilized for industrial heat and electricity generation systems. Higher efficiencies stemming from increased reflectivity of these mirrors are parallel with the sixth priority action of the SET-Plan (Energy efficiency for industry). Finally, developed mirrors would contribute to the fight against climate change by technically supporting the green recovery approach by increasing the overall electricity output of solar thermal systems.
Network	CSP ERANET
Call	2nd CSP Joint Call

Project partner

Number	Name	Role	Country
1	Middle East Technical University Center for Solar Energy Research and Applications (ODTU-GUNAM)	Coordinator	Türkiye
2	Deutsches Zentrum fur Luft-und Raumfahrt e.V. (DLR)	Partner	Germany
3	Sisecam	Partner	Türkiye