a b s t r a c t
We tested whether the colour temperature of the illumination (realised through manipulating the ceiling
light)impacted on thermal comfort, based on the hypothesis that a lower colour temperature is associated
with feeling warmer and a higher colour temperature with feeling cooler. If confirmed, then light might
be a tool for energy-saving through allowing ambient air temperatures to vary over a wider range and
hence reducing the need for space heating and cooling.
Testing took place in a climate chamber. In Study 1, comfort ratings were collected using thermal
comfort surveys (N = 32). In Study 2, an observational design was used, where changes in clothing level,
interpreted as thermal discomfort responses, were observed (N = 32). We compared comfort ratings and
changes in clothing level under light with a colour temperature of 2700K vs. 6500K. Results partly
confirmed the hypotheses: both self-report and observation indicated higher comfort under the low
colour temperature. Further research will need to replicate findings in a real-world setting to see if light
might indeed be a tool to modulate thermal comfort, and hence reduce usage of heating and cooling.
© 2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license