Contents lists available at ScienceDirect Energy Conversion and Management journal homepage: www.elsevier.com/locate/enconman Reducing the power consumption of cascade refrigeration cycle by a new integrated system using solar energy Saman Khalilzadeh, Alireza Hossein Nezhad ⁎ , Faramarz Sarhaddi Department of Mechanical Engineering, University of Sistan and Baluchestan, Zahedan, Iran ARTICLE INFO Keywords: Cascade refrigeration cycle Organic Rankine cycle Solar cycle Waste energy Solar energy ABSTRACT In this paper, to prevent the waste energy and reduce the power consumption in cascade refrigeration cycle (CRC), a new integrated system, including CRC, solar cycle (SC) and organic Rankine cycle (ORC), is proposed. The waste energy in CRC is used to preheat the SC working fluid, thus, the total investment cost is reduced 20% (1099000 $) in comparison with the situation that the CRC’s generated heat is wasted. To investigate the pro- posed system, the energy, exergy, exergoeconomic and exergoenvironmental analyses were carried out. Considering 500 W/m 2 solar radiation for 12 h in a day, it resulted that the coefficient of performance, the energy and exergy efficiencies, and exergoenvironmental impact improvement were obtained as 4.233, 84.53%, 37.05% and 0.6256, respectively. The main exergy destruction was related to solar collectors with 53.10% of total exergy destruction. The unit exergy cost of producing electricity, heating and cooling were calculated as 0.810 $/kWh, 1.395 $/kWh and 0.225 $/kWh, respectively. Meanwhile, the consumed power in the proposed system was reduced by 82.57% in comparison with conventional CRC. Finally, it should be noted that the proposed system could produce 132.72 m 3 /day hot water at 65 °C, and 2400 kWh/day cooling by consuming 567.01 kWh/day power. 1. Introduction Research has shown that the main energy consumption and the main environmental pollution sources are related to power producing, heating and cooling. Usually, fossil fuels are used to provide the re- quired energy for the aforementioned cases. The use of these fuels has caused serious energy and environmental problems. Accordingly, the use of low-temperature energy sources (instead of fossil fuels) and combined cooling heating and power (CCHP) systems (instead of using independent systems) can reduce energy consumption, dependence on fossil fuels, and environmental problems. Regarding the recent explanations, it is essential to use low-tem- perature energy sources, such as renewable energies [1–4], industrial waste heat [5,6], renewable energy technologies’ waste heat [7,8] in CCHP systems. In this way, there will be a system that is capable to meet the required heating, cooling and electricity without using fossil fuels. Vapor compression refrigeration cycle (VCR) and Cascade Refrigeration Cycle (CRC) are among the systems that are utilized to produce cooling by consuming a large amount of electricity. In these systems, the heat produced by the compressors is wasted through the condenser. Although the waste heat has low-temperature, it has a high thermal value. To reduce the power consumption of the compressor and to increase the coefficient of performance (COP), some studies have been done on combining the VCR cycle with the Organic Rankine Cycle (ORC) [9–14] and with the absorption refrigeration cycle (ARC) [15–20]. The results of study [16] showed that by replacing the ARC with the high-tem- perature cycle (HTC) in CRC, the power consumption would be de- creased by 48%–51% and the COP would be increased by 33%. In study [17], a conceptual design was proposed to use the waste heat of naval ships in absorption/vapor-compression cascade refrigeration system. In this design, the cooling at -40 °C for cryogenic, cooling at 5 °C for air conditioning, and water at 48 °C for heating were produced. The results indicated that the proposed design, compared to conventional cascade refrigeration system, would reduce electricity consumption by 31%. In studies [18,19], the thermodynamic analysis of the compressio- n–absorption cascade refrigeration system was carried out. On the other hand, the results of the study [19] showed that if an ejector used in the ARC, the COP of the combined cycle would be increased by 22.6%. In study [20], in addition to combination of the VCR with the ARC, the solar energy was used to provide thermal energy in the generator (through the solar collectors) and to provide compressor’s power (through photovoltaic panels). Finally, the COP of the proposed system https://doi.org/10.1016/j.enconman.2019.112083 Received 14 July 2019; Received in revised form 16 September 2019; Accepted 17 September 2019 ⁎ Corresponding author. E-mail address: nezhadd@hamoon.usb.ac.ir (A. Hossein Nezhad). Energy Conversion and Management 200 (2019) 112083 0196-8904/ © 2019 Elsevier Ltd. All rights reserved. T