Towards low carbon homes – a simulation analysis of building-integrated air-source heat pump systems

A comparative transient simulation analysis for domestic buildings with a floor-embedded heating system coupled to a modern air source heat-pump (ASHP) has been carried out using the TRNSYS numerical modeling environment for various UK locations. The effects of heat-pump control during off-peak electricity tariff periods in conjunction with varying building fabric characteristics were analysed and the results show that for the locations investigated, running costs and CO2 emissions were lower for the ASHP platform than for a comparative gas boiler heating system. It was also found that by utilizing the thermal mass of a concrete floor slab or by integrating external insulation, acceptable comfort levels during the heating season were maintained when operating the ASHP solely during off-peak tariff periods. A thinner concrete floor slab containing phase change material (PCM) provided a slightly improved comfort level during winter and also reduced overheating during summer in buildings with a high level of insulation. Finally, when utilising a floor-embedded PCM material, it was found that the thermal properties of the PCM material must be carefully matched with case-specific building fabric thermal performance parameters in order to ensure effective internal environmental control.

[1]  Goran Strbac,et al.  Demand side management: Benefits and challenges ☆ , 2008 .

[2]  A. Sharma,et al.  Review on thermal energy storage with phase change materials and applications , 2009 .

[3]  Per Fahlén,et al.  Capacity-controlled ground source heat pumps in hydronic heating systems , 2007 .

[4]  Neil Hewitt,et al.  The development of a finned phase change material (PCM) storage system to take advantage of off-peak electricity tariff for improvement in cost of heat pump operation , 2010 .

[5]  Luisa F. Cabeza,et al.  An approach to the simulation of PCMs in building applications using TRNSYS , 2005 .

[6]  T. Y. Chen,et al.  Real-time predictive supervisory operation of building thermal systems with thermal mass , 2001 .

[7]  J. Urchueguía,et al.  Comparison between the energy performance of a ground coupled water to water heat pump system and an air to water heat pump system for heating and cooling in typical conditions of the European Mediterranean coast , 2008 .

[8]  David Jenkins,et al.  Modelling the carbon-saving performance of domestic ground-source heat pumps , 2009 .

[9]  Luigi Schibuola,et al.  SIMPLIFIED MODELS TO SIMULATE PART LOAD PERFORMANCES OF AIR CONDITIONING EQUIPMENTS , 2003 .

[10]  R. Judkoff,et al.  IEA BESTEST In-Depth Diagnostic Cases for Ground Coupled Heat Transfer Related to Slab-on-Grade Construction: Preprint , 2009 .

[11]  Mohammed M. Farid,et al.  Underfloor heating with latent heat storage , 2001 .

[12]  H. Vos.  Trade and Industry , 1946 .

[13]  Behdad Moghtaderi,et al.  Effect of thermal mass on the thermal performance of various Australian residential constructions systems , 2008 .

[14]  Jon Hand,et al.  CONTRASTING THE CAPABILITIES OF BUILDING ENERGY PERFORMANCE SIMULATION PROGRAMS , 2008 .

[15]  P. Eames,et al.  Factors influencing the uptake of heat pump technology by the UK domestic sector , 2010 .

[16]  Nick Kelly,et al.  A comparative assessment of future heat and power sources for the UK domestic sector , 2006 .

[17]  R. Judkoff,et al.  Applying the building energy simulation test (BESTEST) diagnostic method to verification of space conditioning equipment models used in whole-building energy simulation programs , 2002 .

[18]  Nicolas Kelly,et al.  Analysis of retrofit air source heat pump performance: Results from detailed simulations and compari , 2011 .