Australia is the driest inhabited continent on earth, but new research might allow us to use this to create energy.
Scientists in the US have developed a machine that can harness evaporation to create kinetic energy, which can be transformed into power.
Early modelling indicates this technology could generate almost 325 gigawatts if used in the US. In the National Electricity Market – which encompasses the entire east coast of Australia – in 2016-17 there was a maximum demand of 34.4 gigawatts.
Dubbed an “evaporation-driven engine”, it is already achieving positive results and can double as a water-saving device.
It works by using tiny bacterial spores – Bacillus subtilis – that act as sponge-like materials that capture the evaporating water from within a covered source, enlarging as they absorb moisture. When the cover on the water source is opened, the materials dry and reduce in size. This transformation can be converted into power.
“Recent advances in water-responsive materials and devices demonstrate the ability to convert energy from evaporation into work,” the researchers write.
“These materials perform work through a cycle of absorbing and rejecting water via evaporation. These water-responsive materials can be incorporated into evaporation-driven engines that harness energy when placed above a body of evaporating water.
“With improvements in energy conversion efficiency, such devices could become an avenue to harvest energy via natural evaporation from water reservoirs.”
Ozgur Sahin, a Columbia University professor and lead author of the study, believes the process can equal power demand on an hourly basis about 98 per cent of the time, potentially negating the need for external batteries to overcome intermittency issues facing most renewable energy technologies.
“Evaporation comes with a natural battery,” Ahmet-Hamdi Cavusoglu, the other lead author, told Reuters.
“You can make it your main source of power and draw on solar and wind when they’re available.”
Their research adds that in terms of area covered compared with power generated it provides three times the power of wind generation.
Mr Sahin said evaporation could continue on a 24-hour basis as water could store heat, another form of energy.
However the technology has already drawn flak.
Massachusetts Institute of Technology’s James Temple believes it could negatively affect the environment, and on a large enough scale, even alter local weather.
It also is less effective during cooler periods.