A simple invention developed by researchers at Juiz de Fora Federal University in the Brazilian state of Minas Gerais makes it possible to reduce the energy consumed during a hot shower by 30 percent. The newly developed apparatus heats the air in the shower stall, which must be hermetically sealed. As a result, the water temperature needed for a comfortable shower is lowered.

Installed inside the shower stall, the apparatus takes just one minute to raise the air temperature from 15 to 32 degrees Celsius in a two-cubic-meter space. The calculations were based on a 10-minute-long shower and an electric water heater with between 3,000 and 4,500 watts of power.

“Our studies demonstrated that heating the air reduces the use of the highest water temperature. Even when we add the electricity used by the heating apparatus, we observed a 30 percent decrease in average energy consumption,” head researcher Marco Aurélio Alves told Tierramérica.