Analysis of operation and energy consumption of hospital's isolation room

Hospitals, compared with other type of buildings, need the most energy for their Heating Ventilation and Air Conditioning per square meter. Given the need for the reduction of energy use within the built environment it is therefore important to look at possibilities to reduce their energy use. However, this of course has to be done without endangering the primary functions of the hospital. In this case we looked especially at the hospital isolation rooms as they are being used 24/7 and are, compared to other functions, highly energy intensive per m2.
The research started by defining the boundary conditions for ventilation of isolation rooms and the related energy use. It was found that the HVAC energy consumption in isolation rooms is mainly caused by large volumes of air continuously supplying to the rooms, regardless the occupancy of the rooms. As the demand of air change rates and the supply air are different for different type of patients and much less when the rooms are unoccupied, there is a big energy saving potential which could be up to 70% if the ventilation systems of the isolation rooms is controlled according to the occupancy information. It’s difficult to predict the arriving time of the isolation patients. However, it must ensure that when the patients need to be hospitalized in the rooms, the isolation rooms have to be in the standard conditions (e.g. ACH and pressure difference) immediately. Therefore, firstly the response time of the isolation rooms had to be identified. Field tests were done to test the rooms with the ventilation systems operating in three modes: 1) non-occupied mode, 2) normal patient occupancy mode and 3) isolation patient occupancy mode. The seven weeks observation showed that only about 20% of the time the isolation rooms were used by isolation type patients, another 20% time used by non-isolation patients and the left of 60% time the rooms were not occupied. Therefore, the approach for control isolation room ventilation systems using the patient registration information is proposed. It proved that there relevant possibilities to reduce the energy use while maintaining the primary function of isolation in the Intensive Care units.