In honor of the opening of Shepherds Flat Wind Farm
in Oregon this week, the largest wind farm in the United States, let's take look at 'high-altitude wind power', HAWP:
A recent Nature analysis
of potential wind power found that wind turbines placed on Earth's surface could extract kinetic energy at a rate of at least 400 TW, whereas high-altitude wind power could extract more than 1,800 TW. At these rates there would be pronounced climate impacts, but since the world currently uses 18 TW, effectively unlimited.
Accessing HAWP wind is pretty tricky but a number of start-ups are trying. They say it's cheaper and easier to deploy than ground wind technology. The technologies are all different but have the same premise, something like a kite or blimp in the air tethered to the ground.
* Makani Power
(California) is the furthest along to deployment with $20 million backing from Google and ARPA. Makani hopes to build a 92-foot ridged wingspan rated at 600 kilowatts (150 households) (video
), but in the future they want to build a 5-megawatt version with a 213-foot wingspan for offshore.
(Netherlands) is also close to deployment. The kite pulls on the tether on the ground which rotates a turbine. They expect to be operational within a few years.
(California), a helium-filled, blimp-like structure floats 1,000 feet up and the entire balloon spins as the wind blows. It has undergone successful test flights.
(Boston), another a helium-filled device but it basically lifts a standard turbine into the air (video
(California), a soft-wing kite design noted for ease of transport and quick set-up for use in temporary situations (funding from U.S. Marine Corps).
(Germany), uses a similar system as the WindLift.
On the down side, without help from the government, these technologies could take 20 years or more to overcome reliability problems in large scale operation. It's estimated that a $100 million government program could bring that down to 5 years. All of the above fly within a few thousand feet of the ground, the HAWP Holy Grail is the Jet Stream 5 or 6 miles up.
[This post derived from Yale360]