Natural

Building integrated renewable energy sources e.g. photovoltaic system is one of the promised solution for improving energy efficiency in building. However such kind of the system is restrained by irregular power supplied and necessity to convert current from direct to altering form. Therefore, very often the electrical energy generated by photovoltaic system cannot be effectively utilised to supply building devices, e.g. components of HVAC or lighting system.

Application of night cooling to educational buildings looks very promising in mild climates. Night coolingstrategy performance in a school building to be realised in Italy during 2008 has been studied by meansof a commercial CFD code.Due to the symmetry of the building, first a 2D numerical model consisting of a vertical section throughthe three-storey building has been developed. The CFD model includes the solid zone describing theconcrete structure.

Environmental and economic concerns linked to conventional heating, ventilation and air-conditioning systems (HY AC) have sparked a renewed interest in natural ventilation, passive cooling and other low energy microclimate control strategies for buildings. In Canada, the combination of extreme weather conditions, wind variability, transient occupancy patterns and high internal heat gains may hinder the feasibility of implementing natural ventilation as an exclusive means of ventilating non-domestic buildings.