Parabolic trough solar collectors: A general overview of technology, industrial applications, energy market, modeling, and standards

Many innovative technologies have been developed around the world to meet its energy demands using renewable and nonrenewable resources. Solar energy is one of the most important emerging renewable energy resources in recent times. This study aims to present the state-of-the-art of parabolic trough solar collector technology with a focus on different thermal performance analysis methods and components used in the fabrication of collector together with different construction materials and their properties. Further, its industrial applications (such as heating, cooling, or concentrating photovoltaics), solar energy conversion processes, and technological advancements in these areas are discussed. Guidelines on commercial software tools used for performance analysis of parabolic trough collectors, and international standards related to performance analysis, quality of materials, and durability of parabolic trough collectors are compiled. Finally, a market overview is presented to show the importance and feasibility of this technology. We believe the compilation of reviews related to the above aspects will further provide impetus for the development of this technology in the near future

MEGARA, the R=6000-20000 IFU and MOS of GTC

MEGARA is the new generation IFU and MOS optical spectrograph built for the 10.4m Gran Telescopio CANARIAS (GTC). The project was developed by a consortium led by UCM (Spain) that also includes INAOE (Mexico), IAA-CSIC (Spain) and UPM (Spain). The instrument arrived to GTC on March 28th 2017 and was successfully integrated and commissioned at the telescope from May to August 2017. During the on-sky commissioning we demonstrated that MEGARA is a powerful and robust instrument that provides on-sky intermediate-to-high spectral resolutions RFWHM ~ 6,000, 12,000 and 20,000 at an unprecedented efficiency for these resolving powers in both its IFU and MOS modes. The IFU covers 12.5 x 11.3 arcsec 2 while the MOS mode allows observing up to 92 objects in a region of 3.5 x 3.5 arcmin 2 . In this paper we describe the instrument main subsystems, including the Folded-Cassegrain unit, the fiber link, the spectrograph, the cryostat, the detector and the control subsystems, and its performance numbers obtained during commissioning where the fulfillment of the instrument requirements is demonstrated. © 2018 SPIE