Resilient cooling and ventilation for buildings and people

Given that people in urban environments spend most of their lives indoor, the indoor environment is a key aspect regarding human health, comfort, wellbeing, and safety. Climate change induced effects generate uncertainties regarding building resilience, i.e. to absorb impacts and adapt or recover from extreme events (e.g. heatwaves, power outages, wildfires).

In the interest of recycling and upcycling, infrastructure adaptation to extreme events should ideally be representative of flexible heating, ventilation, and air conditioning (HVAC) solutions. In this project experimental investigations and building energy simulations were used to develop, evaluate, and improve i) actively discharged radiant ceiling panels with high thermal capacity, ii) air cleaning systems, and iii) standalone personalised environmental control systems (PECS) as resilient and flexible HVAC solutions.

Results show that the addition and control of thermal mass in the building or HVAC system will, as a thermal storage, mitigate an increase in the room temperature during a heatwave. Air cleaning can improve air quality and/or substitute outdoor ventilation for a similar perceived air quality. PECS could provide effective ventilation and lower the effect of a room temperature increase.

The investigated high thermal capacity radiant ceiling panel showed potential as a resilient cooling technology. The panel can be used to enhance the absorptive, adaptive, and recovery capacity of buildings by using an effective discharge of the thermal mass and restore the thermal buffer during extreme events.

Air cleaning and PECS showed potential as resilient technologies during extreme events with increased outdoor or indoor air pollution. A high clean air delivery rate combined with an effective ventilation strategy represents a resilient, adaptive air quality technology. It allows the complete stop or operation at reduced capacity of ventilation systems for short periods of time. As a standalone multi-functional system for resilient cooling, the PECS requires further development. This was due to the lack of an efficient heat removal from people. A promising alternative is convective cooling with an increased air speed around the person. Considering the increased system complexity, an individual or personalised comfort model is required for automation and control to avoid a potential rebound effect from PECS implementation.