Some of the most powerful (and energy-dense) winds on Earth are literally out of reach of conventional wind turbines, but one wind power startup aims to harvest energy from them with giant kites and some yo-yo action.
The Turin-based startup Kite Gen isn't the only one searching for the holy grail of high altitude wind power, but their approach is a bit different from other methods, which seek to generate power at altitude and then send it down a tether to the ground. The Kite Gen system leaves all of the generating equipment on the ground, saving weight and money in the air, and instead uses the physical traction from the kite's tether to generate electricity.
Once launched, the company's kites are automatically piloted in a predefined flight path (covering a much larger area than a conventional turbine) using on-board avionic sensors to maximize the power generation. The kites are tethered to the ground unit with Dyneema tethers, and the pull on these tethers is what generates electricity. When the kites reach the end of their tether (while turning spinning drums attached to alternators), the angle of the kites are repositioned to present minimum resistance to the wind and the cables are then rewound to begin another phase of power generation. According to Kite Gen, rewinding the cables does consume energy, but only a fraction of what is produced by the kites.
Here's an animated introduction to the new wind power technology:
Kite Gen has raised about $12 million USD in funding, and is currently looking for investors in order to raise an estimated $62 million to take their technology to the next level and build a 150 megawatt wind farm with 50 of their kite units (called Stems).