A 1km-high inflatable solar-energy chimney

December 6, 2013

Similar towers have been built, such as this effort in Spain that was shut down after it began to rust (credit: Schlaich Bergermann und Partner)

Per Lindstrand, the engineer who broke numerous ballooning records with Richard Branson, is hoping to develop a 1km-tall inflatable chimney that can capture energy from the sun, The Engineer reports.

The tower uses rising air heated by the sun to drive turbines. It could provide an alternative to photovoltaic generation in remote areas of seismic activity where maintenance of power lines or solar panels would be difficult.

Lindstrand is consulting with ALMA Observatory in Chile’s Atacama desert, which is looking for a greener alternative to its gas and diesel generators and that was more robust than solar panels.

Lindstrand believes inflatable structures have advantages over concrete, metal or glass models, particularly in desert locations, where the fine sand would clog solar panels, and over metal, which is more complex to fabricate.

To generate enough power for the ALMA observatory, the chimney will need to be 1km high with a 7km-radius canopy at its base to heat the air to drives the turbines.

Lindstrand said that a similar-sized concrete chimney would cost around $750 million but that an inflatable one could be made for as little as $20 million.

This should create a 130MW power station with a capacity factor of 24.7 per cent (much higher than solar PV and on a par with wind turbines), producing 281GWh of electricity a year, according to Patrick Cottam, the Lindstrand Technologies engineer who is designing a 3.5m prototype chimney.

The challenge in constructing a 1km-tall chimney will be in finding a material strong enough to support the high tension forces at the base, with the right flexibility to withstand movement in the wind and the chemical properties to survive many years of exposure to the sun’s ultraviolet light, said Cottam.

H/T Steve Nixon