A novel solar system integrating concentrating photovoltaic thermal collectors and variable effect absorption chiller for flexible co-generation of electricity and cooling. (15th February 2020)

• Record Type: Journal Article
• Authors: Lin, Li; Tian, Yao; Luo, Yu; Chen, Chongqi; Jiang, Lilong
• Is Part Of: Energy conversion and management. Volume 206(2020)
• Publication Date: 2020-02-15
• Subjects: Solar cooling -- Variable effect absorption refrigeration cycle -- Dynamic simulation -- Exergy efficiency -- Concentrating photovoltaic and thermal (CPV/T) collector; 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.2020.112506
• Languages: English
• ISSNs: 0196-8904

Abstract

Highlights: A novel solar system for co-generation of electricity and cooling. More flexible operation due to the variable effect chiller's adaptability. Operating strategy for matching concentrating photovoltaic and thermal collectors with variable effect chiller. Optimal operation offers better performance than using single/double effect chillers. Abstract: Traditional single effect and double effect absorption chillers have relatively narrow working temperature ranges, which limits their application of solar systems. This study proposes a novel solar system integrating concentrating photovoltaic and thermal collectors, and a variable effect absorption chiller, for more flexible and efficient co-generation of electricity and cooling. In this study, variable effect chiller was optimized, showing that three working modes, combined with optimized control, make variable effect chillers a superior choice to the single effect and double effect types. Then, dynamic simulations of the solar co-generation system were performed, in order to study the effects of temperature control on system performance. The results showed that, a high turn-off temperature for the chiller generally results in higher cooling power, shorter working hours for the chiller, and in some cases, a frequent on–off cycling of chiller. With the increase in working temperature level, the cooling exergy efficiency increases, but total exergy efficiency decreases due to the photovoltaic cell's degraded performance. The total exergy efficiency is approximately 32%–33%. A larger difference between turn-on and turn-off temperatures delays the start time of the chiller while ensuring the full use of solar energy. By adjusting the temperature control strategy, the novel solar co-generation system can offer a cooling-electricity ratio from 1.4 to 2.0, which is capable of meeting the demands in many cases. The proposed system offers flexible co-generation of cooling and electricity.