| Abstract: | Based on energy-related measurements, this article evaluates the thermal performance, energy-saving, indirect emissions and financial feasibility of using heat pumps for hotel out-door swimming pools in subtropical climates. A rooftop pool of a city-centre hotel was investigated. It was found that the average coefficient of performance (COP) was around 2.0. The measured electricity consumption was 24.6 MWh and the total heat output was 49.1 MWh for the heating season studied (mid-December to the late April). Compared with conventional electric boilers and gas-fired condensing/non-condensing boilers, the total energy savings during the heating season ranged from 26.5 to 32.5 MWh. Greenhouse and noxious emissions can also be indirectly reduced by about 12,000 kg. A discounting approach was adopted to compute the net present value of fuel costs over a lifecycle of 10 years. It was found that, over a 10-year lifecycle, the energy cost could be reduced by HK$226,400 when a heat pump with an average COP of 2.0 was used instead of a conventional electric boiler. Derived from the energy cost saving over other conventional type of water heating equipment, the simple pay-back period can be about 2 years and the lowest internal rate of return can be 39%. |
