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“Breakthrough” technologies & Other Whirligigs.

whirligigsHardly a week goes by without at least one press release about a new and improved wind turbine design hitting my email inbox. These company press releases touting a breakthrough technology are picked up and propagated by media outlets, which unfortunately bestows credibility on the company. Even more unfortunately, well-intentioned people who want to generate some of their own electricity take the bait.

So, what’s wrong with all of this? And why does the small wind industry take umbrage with these seemingly new designs? Nearly all of the new “breakthrough” technologies share an amazing number of similarities.

Promise: An unusual design, other than the typical two- or three-bladed horizontal axis wind turbine (HAWT). Some are vertical axis or squirrel cages, shrouded or funnels, or some other unusual rotor configuration.

Reality: The designs are simply a regurgitation of something unusual-looking. Although they are eye-catching, they never worked, which is why the designs were abandoned decades ago.

Promise: Rooftop units with small rotors or ground-mounted, designed to generate (“spin”) at lower wind speeds to avoid the added expense of the tower.

Reality: As above, it’s all about collector size and where the fuel is. A whirligig with a small rotor will likely only ever generate enough electricity to overcome the resistance losses in the wire run. Also, note that spinning does not equate to generating electricity. For kicks, calculate the units that go into the power equation in a much-touted 2 mph startup wind speed. Then compare this number with the units in a 10 or 15 mph wind. Do this using P ~ V3.

Promise: The designer claims “thinking outside the box” with an innovative idea, bringing new insights to a stagnant technology.

Reality: Wouldn’t it be good if the innovator knew what’s actually inside the box before beginning to think outside of it? In other words, shouldn’t a designer understand why successful wind turbine designs—small ones, as well as the tens of thousands of utility- and larger-scale wind farm turbines—all look like they do? They should also understand why hundreds of unusual rotor designs were abandoned decades ago and are not being implemented by established manufacturers.

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