Water and energy are the two most fundamental ingredients of modern civilisation and are also the most precious and essential resources around the globe. They are inseparably coupled and with increasing pressures on these resources as the world's populations grow, the concepts of a combined...

Vertical BHE (borehole heat exchangers) are a common solution for GCHP applications (ground coupled heat pump). Correct BHE design and sizing are mandatory to either assure long term GCHP performance or reduce the payback period. Most models for performing the time varying analysis of complex...

Industrial and commercial areas are synonymous with high energy consumption, both for heating/cooling and electric power requirements, which are in general associated to a massive use of fossil fuels producing consequent greenhouse gas emissions. Two pilot systems, co-funded by the Italian...

This study presents experimental and numerical research results in determining an effective borehole thermal resistance of a spiral coil energy pile. A precast high-strength concrete (PHC) energy pile with a spiral coil GHE was installed and thermal response test was carried out to evaluate the...

In groundwater-filled borehole heat exchangers (BHEs) convective flow influences the heat transfer in the borehole. During heat extraction thermal response tests (TRTs) the effect of the changing convective flow is more dominant than during heat injection tests. Water is heaviest around 4 °C...

Borehole Thermal Energy Storage systems typically use U-pipe Borehole Heat Exchangers (BHE) having borehole thermal resistances of at least 0.06Km/W. Obviously, there is room for improvement in the U-pipe design to decrease these values. Additionally, there is a need for methods of getting more...

Thermal performance of vertical U-pipe borehole heat exchanger (BHE) is an important research subject for the design and application of ground-coupled heat pump system (GCHPs). This paper presents an improved evaluation method for thermal performance of BHE based on analytical solution model,...

Energy piles have recently emerged as a viable alternative to borehole heat exchangers, but their energy efficiency has so far seen little research. In this work, a finite element numerical model is developed for the accurate 3D analysis of transient diffusive and convective heat exchange...

Thermal response tests conducted to assess the subsurface thermal conductivity for the design of ground-coupled heat pump systems require a power source of about 7–12kW to heat water circulating in a ground heat exchanger. This high power is commonly supplied with a fuel-fired generator, which...

Technology directed at geothermal energy, one of our renewable energy sources, to heat and air-condition buildings has become very attractive in recent years following the significant developments in ground-source heat pump (GSHP) systems. In general, although the energy efficiency of GSHP...