The wind industry has gone to great lengths over the years to snap up the best properties for its farms, often looking to remote swaths of prairie or distant mountain ridges to maximize energy production and minimize community opposition.

Now, it is reaching for the sky.

With new technology allowing developers to build taller machines spinning longer blades, the industry has been able to produce more power at lower cost by capturing the faster winds that blow at higher elevations. This has opened up new territories, in places like Michigan, Ohio and Indiana, where the price of power from turbines built 300 feet to 400 feet above the ground can now compete with conventional sources like coal.

And efforts to capture the wind could go even higher. In perhaps the most extreme example, a start-up called Altaeros Energies is preparing to introduce its first commercial pilot of an airborne wind turbine in Alaska.

Known as the BAT — or Buoyant Airborne Turbine — the enormous, white helium-filled doughnut surrounding a rotor will float about 1,000 feet in the air and feed enough electricity to power more than a dozen homes through one of the cables tethering it to the ground.