Gary Smith

This floating wind turbine will soon be generating 30kW of wind power from an altitude of 300 metres. "Scientists at Stanford University released a study that said there's enough energy in high-altitude wind to power Earth 100 times over, if only we could harness it," says Adam Rein, cofounder of Boston-based Altaeros Energies. So he and fellow cofounder Ben Glass, 29, conceived the Buoyant Airborne Turbine (BAT), a traditional three-blade turbine and generator housed inside a helium-filled shell.

The BAT is deployed from a trailer on the ground and tethered to a base by three high-strength cables. One of the tethers conducts electricity produced down to the ground, where it can be stored or sent to the grid. On-board sensors automatically adjust the height of the turbine in flight to find optimum wind speed -- 12 to 15 metres a second.


Initial results, Rein says, are encouraging: "We lifted the best-selling small turbine higher than it has ever been deployed, and showed we could get twice the output typically produced on a tower. Plus an environmental assessment showed there was reduced avian and noise impact."

Altaeros is launching an 18-month pilot project in Alaska later this year, with commercial trials in Brazil and India to follow. "There are 100,000 villages in India that still aren't connected to the grid," says Rein. "We have a concept about how the BAT could be adapted to significantly reduce the footprints of offshore wind farms."