Calculating the geo-climatic potential of different low-energy cooling techniques

Energy consumption for space cooling is growing rapidly, increasing the need for alternative low-energy solutions. Passive cooling dissipative systems, based on heat dissipation through heat sinks (air, water, ground, …), can constitute a valid alternative to mechanical cooling at least to reduce the hours in which auxiliary cooling energy is needed. Nevertheless, these solutions are very locally specific and need, from early-design phases, devoted analyses to choose the ones that best fit the local climate. This paper reports an approach to calculate the geo-climatic cooling potential of different heat sinks based on the “virtual” effect that passive cooling systems are expected to have on external air conditions. This approach is based on the elaboration of morphed cooling-degree-day indexes which have been calculated in relation to the effect of comfort and structural ventilation, direct evaporative cooling, and earth-to-air heat exchangers. For each passive solution a devoted simplified model is introduced. Finally, each model is applied on a set of 20 locations in Europe and in the Mediterranean Basin.