A Pilot Study on Geothermal Heat Pump (GHP) Use for Cooling Operations, and on GHP Site Selection in Tropical Regions Based on a Case Study in Thailand

Abstract

In order to reduce electricity consumption, the vertical loop geothermal heat pump (GHP) system coupled with a normal air conditioner was installed in an experimental room in the Parot Racha Building, Chulalongkorn University, Bangkok, Thailand for a comparative, long-term measurement program. The decrease in electricity consumption was approximately 30%. On the basis of the data derived from our measurements, the underground temperature seemed to be consistent and lower than the average outside air temperature, over two years. The underground system consisted mainly of two 50-m-long drilling wells and pipes with a total length of 170 m. The well performance was not examined, but both soil and groundwater aquifer (Bangkok aquifer) at 25 to 50 m. could be utilized for the cooling operation. Moreover, the major controlling factors of electricity consumption were found to be the outside air temperatures and the underground water circulation temperatures. In addition, we considered the geology, underground temperature, and aquifer of Bangkok concluding that almost all Bangkok areas are suitable for GHP installation, except for those where the subsurface temperature is too high compared with the outside air temperature.

Energy Consumption Optimization through Dynamic Simulations for an Intelligent Energy Management of a BIPV Building

“…Thus, for this purpose, the modeling process incorporates and explores the interaction of the thermal and electrical elements in the building. Similar work focusing on the modeling process and optimization of HVAC systems and energy consumption can be found in [26], [27], [28], [29], and [30].…”

A Study on the Operational Condition of a Ground Source Heat Pump in Bangkok Based on a Field Experiment and Simulation

“…Based on this geological survey, a pilot study of the GSHP in Thailand was conducted to demonstrate its energy-savings potential. As a result, a GSHP with vertical-and horizontal-type borehole heat exchangers (BHEs), which is a type of a ground heat exchanger, reduced the electricity consumption by approximately 30% and 18% compared with that of an ASHP, respectively [11,12]. Moreover, the GSHP in Bangkok reduced the life-cycle CO 2 emissions by approximately 28% compared with the ASHP according to a life-cycle inventory analysis of its use in a commercial building [13].…”

“…However, the pilot study conducted in Thailand [11,12] did not elucidate "the performance of the GSHP for the specific heat sink temperature" and "the subsurface temperature increases on long-term GSHP operation". The efficiency of the GSHP/ASHP during cooling operations is decreased by increasing the heat sink temperature, i.e., HP inlet temperature/atmospheric temperature [14].…”

“…(1) An experimental investigation was conducted by using the same pilot facility in the previous study in Bangkok [11] to elucidate the efficiency of a GSHP and ASHP according to the heat sink temperatures. (2) A simulation was conducted that utilized the analytical solution of the heat conduction equation to predict the subsurface temperature increase due to the GSHP operation over the long term.…”

Hybrid Adsorption-Compression Systems for Air Conditioning in Efficient Buildings: Design through Validated Dynamic Models

“…Indeed, as already reported [9], the renewable heating and cooling sector is considered as a "sleeping giant" that, if properly promoted, could further support the diffusion of renewable sources especially in the residential and commercial sector. The heat pump technology is by definition able to exploit renewables, e.g., directly from ambient air [10] or from geothermal heat sources [11]. Nevertheless, the share of renewables guaranteed by standard heat pumps is limited, since they are usually driven by electrical energy.…”