The Readiness Investigation of The Ground Soil Temperature for Underground Heat Exchange Systems Installation in Hot Climates

This present article investigates the possibility of the use of ground soil of hot climates for the investiture of it for cooling and heating aims by using it as an underground heat exchange. The study region is Al-Najaf city, 168.83 km south of Baghdad the capital of Iraq. This heat exchange represents one of the sustainable energy types which depends on the difference between the ambient air and ground soil temperature, which can lead to reducing the exhaustion of fossil fuels. To measure the soil temperatures during all the months of the year, A hole drilled to a depth of 5 meters, seven thermocouples has been installed at each depth (0.5, 1, 2, 3, 4, and 5 m), and at the ground surface. The new experiment result of variation of the soil temperature with depth and during the year has been compared and evaluated in order to estimate the possibility of using Earth to Air Heat Exchanger (EAHE) for heating or cooling purposes along the year. The result shows that the average temperature difference between the ground surface and ground soil temperature during the months increasing as the underground depth increases. The results have let it a perfect referral for the priorities of the use that location at equal to or more than 3 m depth for cooling during summer months (the temperature differences reach to 16.17 oC) rather than heating during winter months (the temperature differences reach to 10.76 oC). The less than 3 m depths can use it for precooling and preheating purposes because it is directly affected by the ambient temperature, which reduces the possibility of using it in a better way. The most significant results were the important negative temperature variances for testing location that becomes an emboldening factor in designing and researching other factors for the build clean, cheap, and efficient ground source heat exchange systems.