An integrated heat recovery air-conditioning system (IHRACS) with double-heating series-wound heat pump part 2: Comprehensive assessment

As an energy-saving scheme in underground commercial space, integrated heat recovery air-conditioning system (IHRACS) with double-heating series-wound heat pump, still need a comprehensive assessment for decision making support when it's competed by other heat recovery schemes. In this paper, analytic hierarchy process (AHP) is used to make multi-analysis, including criterions of energy saving, economic benefit, environment impact and implement convenience. IHRACS and four more alternative schemes, namely exhaust air heat recovery with rotary wheel recuperator, plate-fin recuperator and air-source heat pump (ASHP), and condenser heat recovery with water-to-water heat pump, were assessed at the same time. With emphasis on energy saving and economic benefit, quasi-dynamic modelling on equivalent primary energy saving in year-round, and cost-benefit analysis including net present value (NPV) and benefit-cost ratio (BCR), were implemented respectively. Furthermore, considering what investor and owner concerns differs from policy maker, two comparison matrices were made respectively, and hence two different priority vectors obtained. According to assessment results, although it's the only scheme with capacity of recovering waste heat/cooling all year round and also the most energy saving one, IHRACS is not so economical as exhaust air heat recovery, due to its extremely high cost and relatively low energy price in Harbin. At last, IHRACS owns 0.897 out of 1.0 on policy maker's side (ranked as the first one), but only 0.630 on investor and owner's. It's believed that IHRACS will gradually be accepted by them, with energy price becoming higher and energy saving performing better in most other cities in China.