A new, integrated method to calculate the energy contribution of night ventilation techniques to the cooling load of a building is presented in this paper. The method is based on the principle of "Balance Point Temperature" and permits the calculation of the energy required to cool a building to acceptable comfort conditions when night ventilation techniques are used. It also permits the calculation of the energy contribution of night ventilated buildings compared to conventional air conditioned buildings.

During recent years, energy consumption of buildings for cooling purposes has significantly increased. In order to reduce the energy consumption while maintaining high levels of thermal comfort, building research has been oriented towards the appropriate use of the natural heat sinks. The present paper provides comparative information regarding the performance of the more important passive and hybrid cooling techniques involving the use of a natural heat sink.

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.

A new parametrical model for the prediction of the thermal performance of the earth to air heat exchangers is presen1ed. The system consists of an earth tube, buried in the ground, through which ambient or indoor air is propelled and cooled by the bulk temperature of the natural ground. The proposed model has been developed by analysing temperature data of the circulated air at the pipe's outlet using a systematic parametrical process.