On the cooling potential of earth to air heat exchangers.

The present paper deals with the cooling potential of earth to air heat exchangers. The cooling system consists of an underground pipe laid horizontally where ambient or indoor air is propelled through and cooled by the bulk temperature of the natural ground. The dynamic thermal performance of the system during the summer period and its operational limits have been calculated using an accurate transient numerical model. Multiyear soil and ambient air climatic measurements have been used as inputs to the model. An extensive sensitivity investigation has been performed in order to analyze the impact of the main design parameters on the cooling potential of the system. Cumulative frequency distributions of the exchanger's performance have been developed as a function of all the input parameters. The present paper aims to simplify the procedure for accurate design and performance evaluation of earth to air heat exchangers and to provide information on their cooling potential.