EXPERIMENTAL STUDY OF INDOOR CLIMATE CONTROL USING GROUND SOURCE HEAT PUMP FOR OPTIMIZED ENERGY CONSUMPTION

Abstract

The process of urbanization has given rise to an increased demand for electricity in the building sector, particularly for maintaining thermal comfort. This surge in energy consumption has positioned the building sector as the second-largest consumer of electricity. To address and mitigate this escalating energy demand, various innovative technologies have been explored for heating, ventilation, and air-conditioning. Among these solutions, the ground source heat pump (GSHP) system emerges as a standout performer, proficiently addressing the heating and cooling demand in building compared to conventional air source air-conditioning (ASAC) systems. The aim of this research work is to experimentally study the performance of a GSHP system with 17.58 kW (5-ton) cooling capacity during space heating and cooling mode operations. A detailed analysis of energy saving potential of the GSHP system in comparison to the ASAC system of the same capacity (of two units, 7.023 kW and 10.548 kW) is carried out during space cooling and heating applications. Further, the study intends to understand the capability of the GSHP system during peak hour operations in comparison to the conventional ASAC system. First law analysis of the GSHP systems is performed. Taguchi optimization and sensitivity analysis of the GSHP system are carried out to identify the most influencing parameters that produce higher coefficient of performance (COP) of the GSHP system. The effect of thermal characteristics of building materials used in building enclosure evaluated to study the effect of time lag characteristics during peak hour operation of the GSHP system. In addition, the optimization of building energy consumption for space cooling and heating applications has been conducted using Taguchi method and utility concept. The experiments were performed in a living laboratory at IIT Roorkee, India established with a 17.58 kW cooling capacity GSHP system and the same capacity of ASAC systems. Provisions are made in the experimental facility for the measurement of inlet and outlet temperatures of water flowing in the borehole heat exchangers (BHEs) of the GSHP system, temperature, and relative humidity of air at inlet and outlet of the heat pump and velocity of air. Experiments were conducted on the GSHP system for space cooling and space heating and these experiments were repeated for a few days to obtain reliable experimental data. Similar experiments were carried out on the ASAC systems for the purpose of comparison with the GSHP system.