Assessment of a solar energy powered regenerative organic Rankine cycle using compound parabolic involute concentrator. (15th March 2019)

• Record Type: Journal Article
• Authors: Ustaoglu, Abid; Okajima, Junnosuke; Zhang, Xin-Rong; Maruyama, Shigenao
• Is Part Of: Energy conversion and management. Volume 184(2019)
• Page Start: 661
• Page End: 670
• Publication Date: 2019-03-15
• Subjects: Organic Rankine Cycle -- Non-imaging -- Compound parabolic concentrator -- Involute reflector -- Thermal performance -- Ray tracing; Direct energy conversion -- Periodicals; Energy storage -- Periodicals; Energy transfer -- Periodicals; Énergie -- Conversion directe -- Périodiques; Direct energy conversion; Periodicals; 621.3105
• DOI: 10.1016/j.enconman.2019.01.079
• Languages: English
• ISSNs: 0196-8904

Abstract

Highlights: A novel non-imaging concentrator was adapted to a regenerative ORC. The effect of organic working fluids on collector and cycle performances were evaluated. The best performance was seen in the case of R-141b for small scale applications. For the case of R-141b, collector shows better performance. The best improvement was obtained in the case of water for large scale applications. Abstract: A non-imaging concentrator compound by involute and parabolic concentrator was considered in a regenerative organic Rankine cycle (ORC). The concentrator was covered by vacuumed glass tube to reduce heat loss from the absorber, and to extend the effective life-cycle of optical components. Using the non-imaging concentrator can eliminate the necessity of sun tracking system due to its large acceptance angle. A simulation was carried out for low temperature solar thermal electric generation for various working fluids including dry, isentropic and wet fluids. The results showed the best efficiency of concentrator was observed for the case of R-141b and followed by methanol, R-113, water, benzene and cyclohexane, respectively. The best overall system efficiency was seen in the case of R-141b to be 16.7%. The evaporator pressure was changed as a calculation parameter. The best improvement was obtained for water and R-141b to be 8.8% and 8.3%, respectively. R-141b has a preferable performance because of its low boiling point and can be appropriate for small scales. The increase in evaporator pressure persuades the performance improvement for the case of methanol, water and benzene. It proves that these working fluids can be used for larger scale applications with a better thermal performance.