As soon as the heat is felt with a card intensity, for many the first reaction is to turn on the air conditioner. However, it consumes a lot, with all the indirect consequences in terms of greenhouse gas emissions caused by the production of electricity. But according to a study led by the University of Sydney, at least up to a certain temperature the antiquated and neglected fans remain a very valid alternative, which allows both to maintain adequate comfort and to contain emissions. What’s more: taking advantage of fans instead of air conditioners guarantees a benefit on the environmental impact even higher than the transition from incandescent bulbs to LEDs.
The researchers made their calculations based on five scenarios that involved different combinations of use of the two devices, to understand up to which temperature limit the fans can suffice before people feel uncomfortable and the use of the air conditioner becomes inevitable. And, therefore, to evaluate how much you can save in terms of energy consumption and bill costs limiting the air conditioner to the maximum: a value that can even reach 70% (the estimates refer to consumption in Australia, but the general concept remains valid for other countries as well).
“By increasing the movement of air in an indoor space with fans,” says lead author Ollie Jay, “you can feel yourself equally good at a higher temperature compared to how you would feel at a lower temperature using the air conditioner “. In practice, the temperature threshold that guarantees acceptable comfort is 3-4 degrees higher by cooling the room with the fan. This is possible due to the different operating principles: the fan generates a more intense and faster air flow directly on the skin, effectively dispersing the heat, while the air conditioner lowers the temperature of the environment but moves little air.
“With the sole purpose of lowering the air temperature, the air conditioners power a cycle of high electricity consumptionoften produced by fossil fuel power plants which in turn contribute to a further increase in emissions, ”concludes Professor Jay.
The study was published in The Lancet Planetary Health journal.