In an increasingly connected world, it’s odd that buildings, one of our most controlled environments, consist of multiple but separate systems. Although information from these individual systems are typically integrated and viewed simultaneously on a building wide building monitoring and control system (BMCS) they currently are not responsive to one another. For example, the light switch is entirely independent of the temperature dial. What if we were to link these functions within the digital system that controls a building so that when a high internal temperature is recorded, instead of increasing the cooling to that space, it reduces the colour temperature of the lighting as a first step to making a room feel cooler? And vice versa?
Lighting, along with heating, ventilation and air conditioning (HVAC), is one of the biggest usages of energy in commercial buildings. But as the watts per lumens have dramatically decreased in the last decade through LED technology and lighting control systems with daylight and occupancy sensors have improved, it’s hard to see where lighting technology can go next.
Whether we feel comfortable or not in an office depends on a number of environmental factors including but not limited to: air quality, humidity, acoustic ambience and visual ambience. Recent reports have shown a relationship between the perception of the thermal temperature of a room and the colour temperature of the light. Yes: it seems that our minds trick us into feeling cooler in a room with blue light, and warmer in a room with red light.
During a multidisciplinary workshop, Rebecca raised the idea of creating a feedback loop between systems in the building management system. Rebecca spoke to Dr Richard de Dear, Director of Building Science at The University of Sydney, and the research project was born.
“Perceived temperature is an important criterion in HVAC design. Therefore, we anticipated that changing the colour temperature of lighting in response to thermal set points could help us reduce HVAC energy consumption.” Rebecca explains.
In most commercial, office buildings the internal set point is controlled to 18-24ºC. If that band was widened by two degrees however, we think we could save about 15% in energy on HVAC systems across 30-60% of a building’s rentable area depending on usage profiles.
With the University of Sydney, we’ve installed tuneable white lighting in temperature controlled trial chambers, and programmed cues into the local control systems so that the lighting responds to the temperature of the room. For example, a thermal temperature of 23ºC will trigger the lighting temperature to climb from 4000k (base colour) to 5000k. And conversely, a thermal temperature of 18ºC will trigger the lighting temperature to change from 4000k to 3000k.
If we find that we can indeed trick ourselves into feeling more comfortable based on changes to lighting colour, then we will be able to apply this on projects to improve people’s comfort and wellbeing.
And on top of that, we may be able to reduce energy use in commercial buildings and incorporate this solution into Green Star and WELL Building Standards.
Ask Rebecca about:
We work with industry partners, governments, universities, startups and community organisations. We do this through research partnerships, and as consultants and facilitators for foresight, research, storytelling and technical writing workshops.