If you’re female and feeling too hot or cold in the office, it could be because the HVAC system was set without regards to your physiology – and it’s leading to wasted energy on cooling and heating, according to new research published in Nature Climate Change.
The method for setting temperature for many office HVAC systems – the predicted mean vote/percentage people dissatisfied model – was devised in the 1960s and, in typical 1960s fashion, was based in part on the metabolic rate of “the average man”.
The authors of Energy consumption in buildings and female thermal demand say these methods may overestimate the resting heat production of females by up to 35 per cent, however, leading to buildings being “intrinsically non-energy-efficient in providing comfort to females”.
Researchers Boris Kingma and Wouter van Marken Lichtenbelt argue that as the built environment pushes towards more energy efficient buildings, “indoor climate standards should accurately represent the thermal demand of all occupants”, not just men.
Adjusting these standards to account for gender differences could reduce a building’s energy consumption by avoiding unnecessary levels of cooling in the summer and heating in the winter, they said.
In an experiment the researchers studied the physiology of 16 young women performing light office work. They found the women’s metabolic rate was significantly lower than the standard values, suggesting lower levels of cooling would be needed in the summer for them to feel comfortable.
“Ultimately, an accurate representation of thermal demand of all occupants leads to actual energy consumption predictions and real energy savings of buildings that are designed and operated by the buildings services community,” the researchers said.
The researchers concluded that thermal comfort models needed to “adjust the current metabolic standard by including the actual values for females”.
They said further benefits could be gained by accounting for the effects of sex, body size and scaling the associated metabolic rates to the type of activity undertaken, however more research would be necessary to clarify if that was the case.
In an accompanying News & Views article, Joost van Hoof from the Fontys University of Applied Sciences wrote: “These findings could be significant for the next round of revisions of thermal comfort standards – which are on a constant cycle of revision and public review – because of the opportunities to improve the comfort of office workers and the potential for reducing energy consumption.”
He said the energy saving benefits would also increase as climate change caused higher temperatures that would require more intense airconditioning.
However, he said because of a small sample size, a large-scale re-evaluation in field studies might be needed “in order to sufficiently convince real estate developers, standard committees and building services engineers”.