The performance of split and integrated types of air-source heat pump water heaters in South Africa

  • Stephen Loh Tangwe Fort Hare Institute of Technology, University of Fort Hare, Alice, South Africa https://orcid.org/0000-0002-6936-9629
  • Michael Simon Fort Hare Institute of Technology, University of Fort Hare
  • Russel Mhundwa Fort Hare Institute of Technology, University of Fort Hare https://orcid.org/0000-0002-5031-1697
Keywords: coefficient of performance; vapour compression refrigeration cycle; renewable energy technologies

Abstract

Renewable energy technologies that can provide optimum and cost-effective energy savings to mitigate global warming, energy crisis and to achieve energy efficiency continue to be of paramount importance. The present study focused on identifying critical parameters such as the volume of hot water drawn off; ambient temperature; relative humidity; refrigerant temperatures at the inlet and outlet of the compressor and condenser; and deterministic quantities such as time used, power consumption and coefficient of performance (COP) as indicators to benchmark the performance of both the split and integrated types of air-source heat pump (ASHP) water heaters. The basis for analysis was on two predominant scenarios: first-hour heating rating and the heating cycle due to controlled volume of hot water drawn-off wherein both the integrated and split types ASHP water heaters experienced vapour compression refrigeration cycles. A data acquisition system was constructed and implemented to monitor the performance of both systems. The results obtained during summer season showed that, under the scenario of 150 L hot water withdrawal, the average COP of the systems was 3.18 and 2.85 for the split and integrated types respectively. The average power consumed was 1.29 (split type) and 0.85 kW (integrated type). The times of operation were 84 minutes (split type) and 138 minutes (integrated type).

Author Biographies

Stephen Loh Tangwe, Fort Hare Institute of Technology, University of Fort Hare, Alice, South Africa

Stephen Tangwe holds a B.Eng. (Hons) and M. Eng degree in Electrical Engineering from AIU, Honolulu, Hawaii. He is an IEE Graduate student and also an IEE Power and Energy society member. At present, he is a graduate student member in the South Africa Institute of Electrical Engineers and his an adhoc Eskom M&V Engineer with the university of Fort Hare team. He is also an energy efficiency research candidate with Fort Hare Institute of Technology and a MATLAB application Engineer. He is a seasoned author and reviewer in many accredited peer review journals and conference proceedings.

Tel:0783076922; Email: stangwe@ufh.ac.za

Michael Simon, Fort Hare Institute of Technology, University of Fort Hare

Michael Simon holds a PhD degree in Physics from the University of Fort Hare. He is presently the university of Fort Hare Energy Manager and Head of the Energy Efficiency Group in FHIT. He is also a certified Eskom M&V professional and Team leader of the Eskom M & V team of the university of Fort Hare. He is a Photo Voltaic & an Energy Efficiency specialist.

Russel Mhundwa, Fort Hare Institute of Technology, University of Fort Hare

Russel Mhundwa holds a Ph.D. degree in Physics from the University of Fort Hare. He is an ad-hoc Eskom M&V Technician with the UFH team. He is a certified Professional Physicist (Pr.Phys), a member of SAIP and SAEE. He is also a renewable energy specialist.

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Published
2018-06-22