Next Article in Journal
A User-Oriented Ethnographic Approach to Energy Renovation Projects in Multiapartment Buildings
Next Article in Special Issue
A Bibliometric Study on Integrated Solar Combined Cycles (ISCC), Trends and Future Based on Data Analytics Tools
Previous Article in Journal
“We’re Made Criminals Just to Eat off the Land”: Colonial Wildlife Management and Repercussions on Inuit Well-Being
Open AccessArticle

Energy Analysis of a Novel Ejector-Compressor Cooling Cycle Driven by Electricity and Heat (Waste Heat or Solar Energy)

1
Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117575, Singapore
2
Department of Mechanical Engineering, University of Engineering and Technology, GT Road, Lahore 54000, Pakistan
3
School of Mechanical, Biomedical and Design Engineering, College of Engineering and Applied Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
*
Author to whom correspondence should be addressed.
Sustainability 2020, 12(19), 8178; https://doi.org/10.3390/su12198178
Received: 4 August 2020 / Revised: 25 September 2020 / Accepted: 25 September 2020 / Published: 4 October 2020
(This article belongs to the Special Issue Advances in Solar Thermal Energy)
Low-grade heat is abundantly available as solar thermal energy and as industrial waste heat. Non concentrating solar collectors can provide heat with temperatures 75–100 °C. In this paper, a new system is proposed and analyzed which enhances the electrical coefficient of performance (COP) of vapour compression cycle (VCC) by incorporating low-temperature heat-driven ejectors. This novel system, ejector enhanced vapour compression refrigeration cycle (EEVCRC), significantly increases the electrical COP of the system while utilizing abundantly available low-temperature solar or waste heat (below 100 °C). This system uses two ejectors in an innovative way such that the higher-pressure ejector is used at the downstream of the electrically driven compressor to help reduce the delivery pressure for the electrical compressor. The lower pressure ejector is used to reduce the quality of wet vapour at the entrance of the evaporator. This system has been modelled in Engineering Equation Solver (EES) and its performance is theoretically compared with conventional VCC, enhanced ejector refrigeration system (EERS), and ejection-compression system (ECS). The proposed EEVCRC gives better electrical COP as compared to all the three systems. The parametric study has been conducted and it is found that the COP of the proposed system increases exponentially at lower condensation temperature and higher evaporator temperature. At 50 °C condenser temperature, the electrical COP of EEVCRC is 50% higher than conventional VCC while at 35 °C, the electrical COP of EEVCRC is 90% higher than conventional VCC. For the higher temperature heat source, and hence the higher generator temperatures, the electrical COP of EEVCRC increases linearly while there is no increase in the electrical COP for ECS. The better global COP indicates that a small solar collector will be needed if this system is driven by solar thermal energy. It is found that by using the second ejector at the upstream of the electrical compressor, the electrical COP is increased by 49.2% as compared to a single ejector system. View Full-Text
Keywords: ejector; low-grade heat; CCP; vapour compression; VCC; refrigeration; efficiency; energy ejector; low-grade heat; CCP; vapour compression; VCC; refrigeration; efficiency; energy
Show Figures

Figure 1

MDPI and ACS Style

Riaz, F.; Tan, K.H.; Farooq, M.; Imran, M.; Lee, P.S. Energy Analysis of a Novel Ejector-Compressor Cooling Cycle Driven by Electricity and Heat (Waste Heat or Solar Energy). Sustainability 2020, 12, 8178.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop