A numerical model to calculate the performance of multiple, parallel, earth-to-air heat exchangers is described, The system consists of N parallel earth tubes, buried in the ground, through which ambient or indoor air is propelled and cooled by the bulk temperature of the natural ground. The technique of superposition was used for analysis of the thermal process. The proposed model has been successfully validated against experimental data. The cooling potential of the system under real climatic conditions was investigated while operational limits of the system were analyzed using as inputs to the model multi-year soil and ambient air-temperature measurements. An extensive sensitivity investigation has been performed to analyse the impact of the main design parameters on the cooling potential of the system.