Design and thermoeconomic analysis of a solar parabolic trough – ORC – Biomass cooling plant for a commercial center

• Published in: Solar energy 2021-02, Vol.215, p.92-107
• Main Authors: Pina, Eduardo A., Lozano, Miguel A., Serra, Luis M., Hernández, Adrian, Lázaro, Ana
• Format: Article
• Language: English
• Subjects: Biomass; Carbon dioxide; Carbon dioxide emissions; Commercial center; Cooling systems; Cost analysis; Design; Economic analysis; Economics; Electricity; Electricity consumption; Energy consumption; Energy storage; Heat recovery; Hybrid systems; Internal flow; ORC; Parabolic trough collector; Rankine cycle; Sensitivity analysis; Solar collectors; Solar cooling plant; Solar energy; Solar heating; Sustainable energy; Thermal energy; Thermoeconomic analysis
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2020.11.080

•Hybrid PTC-TES-biomass ORC-based polygeneration system design for a commercial centre.•The system produces the annual electricity consumed in the commercial centre.•Thermoeconomic analysis provides the cost of the internal flows and final products.•Investment costs reduction leads to system economic feasibility in the medium term.•The system displaces 96.1% of the CO2 emissions relative to a conventional system. Hybrid renewable polygeneration systems are regarded as key solutions for the sustainable energy supply of buildings. While solar heating and cooling comprises a wide range of technologies, there has been limited research on the combined production of power and cooling only, with little or no heat demand. This study designs and analyzes a hybrid solar–biomass ORC-based polygeneration system from energy, economic, and environmental viewpoints. The polygeneration system is designed to cover the electricity and cooling demands of a commercial center located in Zaragoza, Spain. A parabolic trough collector field coupled with thermal energy storage, and an auxiliary biomass boiler supply heat to an Organic Rankine Cycle (ORC), which generates electricity to cover electrical demands and to produce cooling in mechanical chillers. The biomass boiler supports the solar thermal production to ensure a stable and reliable heat supply to the ORC. The system is connected to the electric grid, so that electricity purchases and sales are possible. The equipment sizing is performed with the goal of achieving a high renewable fraction in the total electricity consumed by the commercial center. The analysis of the proposed plant includes the hourly operation throughout the year, complemented by an economic assessment, considering investment and operation costs, and an estimate of the environmental benefits of the plant. Also, a thermoeconomic analysis is developed to determine the cost formation process of the internal flows and final products of the plant. The unit cost of each flow is broken down into investment and operation cost components. Sensitivity analyses of the investment cost, interest rate, biomass price, and electricity selling price discount are made. The results show that, in economic terms, the system is not presently viable, since the cost of the electricity produced (279.07 €/MWh) is much higher than the electricity purchase price (126.70 €/MWh). In environmental terms, the system is capable of displacing 96.1% of the CO2 emissions and 85.6% of no