Innovative Passive Cooling in Healthcare

Session 3 Paper 1, CIBSE ASHRAE Technical Symposium, Imperial College, London, UK
18th and 19th April 2012

This report explores an innovative passive cooling system adopted at the naturally ventilated Houghton-le-Spring Primary Care Centre near Sunderland, UK. The central feature of the system is a thermal wall which extends along the length of the building, which is split into a series of individual shafts to separate the ventilation of the interior spaces.

In summer, air is provided naturally using a displacement ventilation strategy and uses the thermal wall for passive pre-cooling of the incoming air. The partitioning of the mass into a series of individual shafts which are independently controlled provides a host of new approaches including localised cooling and staged release of the cooling potential. The thermal wall is multi-functional and allows for a natural mixing ventilation strategy to be used in winter where displacement ventilation would necessitate significant pre-heating of the incoming cold air.

The modelling suggests that the thermal wall provides an equivalent of 2-4MWhrs per year of cooling for the waiting area or 6-8MWhrs for all the rooms ventilated from the wall. The initial monitoring data suggests that the model can be used to provide a close estimate of the temperature of the cooled air provided by the thermal wall.