Comfort and energy consumption analysis in buildings with radiant panels

A new methodology has been introduced for an overall and quantitative evaluation of comfort and energy consumption of an office room with a ceiling radiant heating system, radiator heating system, or a warm air heating system. The airflow program, PHOENICS-84, is used to study the three-dimensional distributions of indoor air velocity, air temperature, turbulent energy, and contaminant concentration in the room. With these results a draught risk distribution in the room can be numerically investigated. It has been found that the radiator heating system offers the best comfortable environment and the radiant heating system is better than the warm air heating system. The results also show that the radiant temperature asymmetry and the temperature difference between the enclosure surfaces and the room air are in the permissible comfort range in all the heating systems. The energy consumption of the room with the three different heating systems is determined by using the air-conditioning load program ACCURACY. It may be concluded that the radiant heating system uses 17% more energy than the other two systems. The main reason is that the ceiling heat capacity is very large and a great amount of heat is stored during office hours. The heating loads of the radiator heating system and the warm air heating system are nearly the same regardless of the energy used for the ventilators.