energies Article Comparative Analysis and Design of a Solar-Based Parabolic Trough–ORC Cogeneration Plant for a Commercial Center Eduardo A. Pina , Luis M. Serra * , Miguel A. Lozano , Adrián Hernández and Ana Lázaro Group of Thermal Engineering and Energy Systems (GITSE) of Aragon Institute of Engineering Research (I3A), Department of Mechanical Engineering, Universidad de Zaragoza, Calle María de Luna sn, 50018 Zaragoza, Spain;
[email protected] (E.A.P.);
[email protected] (M.A.L.);
[email protected] (A.H.);
[email protected] (A.L.) * Correspondence:
[email protected]; Tel.: +34-976-761913 Received: 24 August 2020; Accepted: 10 September 2020; Published: 14 September 2020 Abstract: This paper performs technical, economic and environmental feasibility analyses of two different solar cogeneration plants, consisting of a solar system (a parabolic trough collector field coupled with thermal energy storage), an Organic Rankine Cycle (ORC), and mechanical chillers, that should cover the electrical and cooling demands of a commercial center located in Zaragoza (Spain). System A is hybridized with an auxiliary biomass boiler that complements the solar system’s thermal production, providing a constant heat supply to the ORC, which operates at full load during the operating hours of the solar system. In contrast, system B is not hybridized with biomass, so the ORC is fully driven by the solar system, operating at partial load according to the solar resource availability. Both systems are connected to the electrical grid, allowing electricity purchases and sales when needed. The design procedure involves the sizing of the equipment as well as the modelling of the hourly behavior of each system throughout the year.