María José Montes

Methodology for the thermal characterization of linear Fresnel collectors: Comparative of different configurations and working fluids

Linear Fresnel collectors are becoming an attractive option to generate electricity from solar radiation. This paper is focused in the thermal performance of Fresnel collectors working with different heat transfer fluids: synthetic oil, water-steam, molten salt and air, also comparing the results of the Fresnel technology with those obtained in reference parabolic trough loops. Although there are two basic designs of the Fresnel receiver: multi-tube and single-tube with secondary concentrator, this work only studies in depth the single-tube option, as this design is more suitable for a proper comparison with parabolic troughs. The receiver in parabolic troughs has been modeled as an evacuated tube with a selective coating and a glass cover. For Fresnel receivers it has been simulated two different configurations: non-evacuated receiver, with a glass window at the cavity aperture and evacuated receiver, characterized by a tube with a glass cover and a selective coating.