Heating water and tap water production with an air-to-water heat pump by using the waste heat of an oil-free air compressor

Abstract

Existing buildings require optimization of the individual heating systems to decrease the energy consumption or energy use intensity (EUI) with heat recovery systems to maintain the sustainability. In terms of energy use intensity, hospitals are considered as the second highest EUI among diverse types of buildings. Therefore, to decrease energy use intensity in hospitals heat recovery options have to be analysed. In this application, oil-free air compressors' waste heat is recovered by using air-to-water heat pumps for providing hot tap water (around 10% of total) during summer mode and heating water for radiators placed in an emergency waiting room (42 m2 area) during winter mode at Gazi University Hospital, in Turkey. The results showed that previously the unserviceable area get in use with a PMV value of +1. The payback period for the implemented system is found to be 2-4 years depending on heat load variations.