cooling potential

Even in Northern European climates, overheating in many Nearly Zero Energy Buildings is a barrier to year round occupant satisfaction with the indoor thermal environment. Improved energy performance and enhanced thermal comfort should not be perceived as a rigid dichotomy of concepts. However, an acceptable thermal environment, during extended cooling periods now present in NZEB’s, can come at a high energy cost if mechanical cooling is used.

We introduce a new method for defining ventilative cooling potential (VCP) for office buildings that depends not only on the climatic conditions but also on building thermal characteristics. The energy savings from ventilative cooling differs from building to building; therefore, VCP should be able to represent the actual energy savings—though not perfectly—in order to guide optimization of ventilative cooling parameters during the initial design stage.

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.