Energy saving possibilities with cooled-ceiling systems

Based on hour-by-hour simulation studies, this paper presents the annual energy consumption characteristics of water-panel type cooled-ceiling systems in comparison with conventional all-air systems. In particular, some unique energy saving measures associated with cooled-ceiling systems are numerically studied. The results indicate that a cooled-ceiling system can save much of the fan energy required in all-air systems, and that in the temperate Dutch climate, the system has a compatible energy performance with a VAV (variable air volume) system for office-building cooling purposes. The energy saving possibilities studied include using ceiling water to pre- or re-heat ventilation air and using a cooling tower for free cooling. The paper also demonstrates the possibilities of using a simulation technique to estimate non-conventional energy efficient system designs.