Applications of building-integrated coil-type ground-coupled heat exchangers—Comparison of performances of vertical and horizontal installations

Abstract The building-integrated coil-type ground-coupled heat exchanger (GCHE) was used to overcome the high installation cost of the heat exchanger. A field test and simulations were conducted to analyze the performance of GCHE when installed vertically or horizontally. The vertical GCHE refers to the coil-type GCHE installed at the center of a PHC (pre-stressed high-strength concrete) pile used for the building foundation. The horizontal GCHE refers to the coil-type GCHE laid horizontally on the bottom of the building. The amount of electric power consumed by the horizontal GCHE system was higher than that consumed by the vertical GCHE system. The coefficient of performance (COP) through a cooling experiment was identified as 3.9–4.3 for the vertical type and 3.3–3.7 for the horizontal type. The simulation model was used to examine the annual performance evaluation for the vertical and horizontal GCHEs. The comparison of the year-round energy consumption values showed that the vertical GCHE has about 15% higher heating/cooling efficiency than the horizontal GCHE. The return period was six years in both the horizontal and vertical GCHEs for the short term, but the cost saving in the vertical GCHE was about 28% higher in the long term.

[1]  Hikari Fujii,et al.  NUMERICAL MODELING OF SLINKY-COIL HORIZONTAL GROUND HEAT EXCHANGERS CONSIDERING SNOW COVERAGE EFFECTS , 2013 .

[2]  A. Inaba,et al.  CO2 payback–time assessment of a regional-scale heating and cooling system using a ground source heat–pump in a high energy–consumption area in Tokyo , 2002 .

[3]  M. E. Suryatriyastuti,et al.  Understanding the temperature-induced mechanical behaviour of energy pile foundations , 2012 .

[4]  Hyunku Park,et al.  Evaluation of thermal response and performance of PHC energy pile: Field experiments and numerical simulation , 2013 .

[5]  Josua P. Meyer,et al.  Economic potential of vertical ground-source heat pumps compared to air-source air conditioners in South Africa , 1998 .

[6]  Guohui Gan,et al.  Experimental measurement and numerical simulation of horizontal-coupled slinky ground source heat exchangers , 2010 .

[7]  Mustafa Inalli,et al.  A techno-economic comparison of ground-coupled and air-coupled heat pump system for space cooling , 2007 .

[8]  W. H. Leong,et al.  Analysis of ground source heat pumps with horizontal ground heat exchangers for northern Japan , 2009 .

[9]  Shuntaro Inoue,et al.  Experimental study of several types of ground heat exchanger using a steel pile foundation , 2011 .

[10]  Abdeen Mustafa Omer,et al.  Ground-source heat pumps systems and applications , 2008 .

[11]  V. I. Ugursal,et al.  Performance and economic feasibility of ground source heat pumps in cold climate , 1997 .

[12]  Apostolos Michopoulos,et al.  Operation characteristics and experience of a ground source heat pump system with a vertical ground heat exchanger , 2013 .

[13]  Konstantinos Papakostas,et al.  On the evaluation of design parameters effects on the heat transfer efficiency of energy piles , 2011 .

[14]  Jean Yee Hwa Yang,et al.  Experience on the application of a ground source heat pump system in an archives building , 2011 .

[15]  Hongxing Yang,et al.  Vertical-borehole ground-coupled heat pumps: A review of models and systems , 2010 .

[16]  Yi Man,et al.  Heat transfer analysis of pile geothermal heat exchangers with spiral coils , 2011 .

[17]  Sepehr Sanaye,et al.  Thermal-economic modeling and optimization of vertical ground-coupled heat pump , 2009 .

[18]  Xu Zhang,et al.  Thermal performance and ground temperature of vertical pile-foundation heat exchangers: A case study , 2008 .

[19]  Mustafa Inalli,et al.  Technoeconomic appraisal of a ground source heat pump system for a heating season in eastern Turkey , 2006 .

[20]  Yasuhiro Hamada,et al.  Field performance of an energy pile system for space heating , 2007 .

[21]  Georgios A. Florides,et al.  Ground heat exchangers—A review of systems, models and applications , 2007 .

[22]  Sepehr Sanaye,et al.  Horizontal ground coupled heat pump: Thermal-economic modeling and optimization , 2010 .

[23]  Josua P. Meyer,et al.  A techno-economic analytical comparison of the performance of air-source and horizontal-ground-source air-conditioners in South Africa , 1997 .

[24]  Taeyeon Kim,et al.  Thermal performance analysis of a ground-coupled heat pump integrated with building foundation in summer , 2013 .

[25]  Doosam Song,et al.  Performance evaluation of a radiant floor cooling system integrated with dehumidified ventilation , 2008 .

[26]  Lin Lu,et al.  Investigation on heat transfer around buried coils of pile foundation heat exchangers for ground-coupled heat pump applications , 2012 .

[27]  Gianpiero Colangelo,et al.  CFD simulations of horizontal ground heat exchangers: A comparison among different configurations , 2012 .

[28]  Guohui Gan,et al.  Simulation of thermal performance of horizontal slinky-loop heat exchangers for ground source heat pumps , 2013 .

[29]  Hongxing Yang,et al.  A new model and analytical solutions for borehole and pile ground heat exchangers , 2010 .