Design of a space cooling plant from residual energy of ORC-GSHP assisted geothermal power plant at Dholera, Gujarat, India

Abstract

More than 45% of the nations around the world use geothermal energy for a wide range of direct and indirect applications pertaining to its stable nature. This paper explores the use of geothermal energy for the direct application of space cooling in residential and commercial applications. It introduces a low enthalpy geothermal energy utilizing space cooling system, a complimentary system to the Organic Rankine Cycle (ORC)-Ground Source Heat Pump (GSHP) assisted geothermal power plant. The configuration of the whole system, including the cooling, heating, and common circuits, is discussed. The main components of the space cooling system consist of Plate Type Heat Exchanger (PHE), GSHP, Air Handling Unit (AHU), and ORC. This study also built a mathematical model based on heat transfer for heat exchangers, Coefficient of Performance (COP) of heat pump, and cooling load of the AHU. For system observation and analysis, the experimental data collected over the course of 90 days (March to May) has been used. The results show that geothermal systems can be an effective and efficient way to cool spaces. A room temperature of 18 ℃ is achieved for an outside ambient temperature range from 19 to 46℃ in summer conditions. The system output placed GSHP's COP from 1.6 to 4 and the AHU's average cooling load is 58.29 kWh with a heat exchange effectiveness rate of 0.46. The system with a few modifications can also be utilized for space heating during winter and other direct applications during summer.