For state of the art buildings ventilation heat loss can exceed 50 percent of the total heat loss of the building. Balanced ventilation systems with heat recovery from the exhaust air lead to bjg costs for ducts. Alternatively, the incoming air of exhaust ventilation systems can be pre-heated by curtain wall facades. A newly developed simulation program for transient analysis of curtain wall systems is validated by measurements. Parameter studies for pre-heating air with curtain walls are presented. Location, orientation, construction, and geometry are considered.

A systematic analysis of ventilation efficiency of indoor climate in buildings is required. The article gives the strategy of that procedure and individual parameters of thermal environment and indoor air quality that must be taken into account. The discrepancies between the actual and projected values is limited. The same applied to energy use. Besides the analysis of air velocity at analyz ed spot the assessment and evaluation of local air turbulence intensity is necessary as well.

The thermal performance of the underground airpipe air conditioning system constructed at the Non-Conventional Energy Research Institute, Ghosi has been studied. The heat exchanger is used in recirculation mode to aircondition eight rooms in a guest house at the Institute. The temperature and relative humidity of a conditioned and non-conditioned room are measured every two hours. The cooling potential of the system is estimated. It is observed that reasonably good thermal comfort conditions can be created in the building with such a system.

This latest addition to the University of East Anglia Campus cost 20 per cent less to build than a conventional building of similar proportions and uses 80 per cent less energy.