As the UK swelters in record-breaking May temperatures of 35°C, a scientist has warned that using electric fans at night may not provide the cooling relief many expect. New research from the University of Ottawa suggests that fans are largely ineffective during extreme heat, particularly for vulnerable groups such as the elderly.
According to Science How Stuff Works, fans do not lower a room's temperature but can actually increase it slightly due to the motor's heat output. The perceived cooling effect comes from air movement aiding sweat evaporation, but this is diminished in high humidity or when ambient temperatures exceed 33-35°C.
Lead researcher Professor Robert Meade stated: 'Fans do improve sweat evaporation, but this effect is not strong enough to significantly lower your body's internal temperature when it's already really hot. In older adults, who may have a reduced ability to sweat, fans provide even less cooling benefits.'
The study, published in Science Daily, used human heat balance modelling to assess fan effectiveness across over 116,000 scenarios. Results consistently showed that fans do not match the cooling power of air conditioning, and health organisations are urged to caution against relying on fans during heatwaves.
Instead, the focus should be on ensuring access to alternative cooling methods like air conditioning, while exploring more sustainable options. The warning comes as millions across the UK struggle to stay cool during the unprecedented heatwave.
