Heating energy-saving potentials in HVAC system of swimming halls: A review

Swimming halls (SHs), which belong to special building sector, are easily overlooked as significant energy users and carbon producers. The demands of heat (e.g., pool water heating, domestic hot water, space and supply air heating) and electricity (e.g., Saunas, pool pumping and ventilation) in SHs are both very high, which indicates the high energy saving potentials. This paper comprehensively introduced and summarized the energy-saving potentials mainly for the heating system in SHs. After briefly introducing the global energy and building energy backgrounds, the energy system of SHs was firstly introduced, including its energy use and breakdown, ventilation demand, and heat losses. Then, renewable and sustainable energy sources applied in SHs were reviewed, especially solar energy application in terms of individual solar-assisted heating and hybrid solar-assisted heat pump systems, while geothermal and biomass and other energy applications were also introduced briefly. Furthermore, building energy management (BEM) strategies were introduced and summarized comprehensively, including waste heat utilization, prediction of energy demand and consumption, control and optimization of HVAC system, and demand response potentials of both electricity and district heat. In the discussion part, the recommendations of high-efficient or energy-saving technologies in SHs were given as well as the future development. Finally, suggestions were given for achieving energy efficiency and carbon reduction in SHs via using renewable energy sources (especially solar energy), optimizing the energy and HVAC systems, possible waste heat recoveries, and applying demand response of energy. In addition, establishing feasible and comprehensive energy indexes to evaluate energy use in SHs is also essential in the future.