Economic Priority Map for Horizontal Geothermal Heat Pump Installation Using R600a as a Natural Refrigerant

Document Type : Research Article


Department of Mechanical Engineering, Shahrood Branch, Islamic Azad University, Shahrood, I.R. IRAN


Growing attention to the Geothermal Heat Pump (GHP) system highlights the necessity of using the technology in an optimized way. Since geographic and meteorological conditions have substantial effects on the efficiency of GHP, a technical and economic feasibility study on a regional scale was performed on residential buildings using R600a as a natural refrigerant. The investigation consists of numerical modeling and enhancement of Horizontal Geothermal Heat Pump Systems (HGHP) by a meta-heuristic algorithm, spatial cooling/heating design load calculation, and regional data exploration to attain a priority map based on economic factors of 96 geographical points in Iran as a case study. The modeling and optimization approach validation was investigated by comparing the computed results with those published in references. Particle Swarm Optimization (PSO) was used as an optimization tool due to its simplicity and accuracy. The effects of geographical factors, including heating & cooling load, cooling to heating load ratio, and different soil types on the objective function, and Total Yearly Cost (TYC) were presented in a table and investigated to have a better picture in a general exploration study. Finally, Iran's HGHP priority map was accurately presented in this study to help policymakers with decisions concerning technology subsidization. This map helps the investigators to have a better picture of the total affecting parameters on GHP system installation.


Main Subjects

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