18 May 2017

K.1.7.1 Vapour Compression Heat Pump Technologies for Domestic Hot Water Heating


Decarbonising space heating in domestic buildings has advanced through combinations of building insulation and lifestyle changes e.g. Passive House, integration of renewable energy and the use of heat pumps and other energy efficiency measures. Domestic Hot Water energy savings have also proceeded through improved water usage of “white goods”, aerated taps, improved storage tank designs and once again lifestyle changes. However, combination boilers (gas and oil) have made significant inroads into hot water storage tank deployment which has in turn affected variable renewable energy demand side management potential at a domestic level. Therefore, in terms of hot water decarbonisation, can the vapour compression heat pump respond with similar personal expectations in terms of heat-up time and flow rates to that of the combination boiler for domestic hot water usage? A new UK Engineering & Physical Sciences Research Council project entitled 4S-DHW (EP/N021304/1 Small Smart Sustainable Systems for future Domestic Hot Water) aims to evaluate the latest wide speed range variable speed scroll compressors as a direct competitor to the combination boiler. Initial concepts will devise domestic hot water use patterns for individual homes including temperature, flow rates durations and drive a compressor to meet these needs. Based on the response of the compressor, minimal indirect water heating provided through novel thermal energy storage utilising will be integrated into the heat pump to meet end-user demands. This paper describes likely concepts that can meet this need, experimental development and initial modelling indications.