Despite explosive growth, wind energy is still a fledgling industry compared to coal or oil. Although advances in efficiency are announced with increasing frequency, one of the biggest challenges is finding a way to make wind cost competitive with fossil fuels. A new technology from Tunisia-based Saphon Energy could be key to making the next big leap toward more efficient wind power as well as lower production costs.
Saphon is responsible for something called Zero-Blade Technology: a wind turbine design that completely eliminates the need for the three blades that have now become synonymous with wind energy. According to Hassine Labaied, Saphon’s CEO, the design is mainly inspired by the mechanism of a sail boat, and is a new and better way to collect wind’s kinetic energy.
In the bladeless turbine, blades are replaced by a sail-shaped body while both hub and gearbox are removed. Instead of spinning the blades’ rotor, the wind is being harnessed by a sail which follows a non-rotational back and forth motion. According to Saphon’s website, such movement follows a knot path and allows the conversion of the majority of the kinetic energy into mechanical energy (using pistons). The same is then converted to a hydraulic pressure that could either be stored (in hydraulic accumulator) or instantly converted to electricity via a hydraulic motor and a generator. The aerodynamic shape means drag force becomes the driving force of the system while the lift force becomes almost nil.
The company claims that zero-blade technology is capable of overcoming the Betz limit, which states that no turbine can capture more than 59.3 percent of the wind’s kinetic energy. On average, a bladed wind turbine can only capture 30 percent to 40 percent.
Also, without the need to construct and then transport the massive turbine blades into what are usually remote areas, the company hopes to catalyze a drastic reduction in turbine production.
So far, Saphon has patented the Zero-Blade Technology and is now looking to partner with a major manufacturer to bring the technology to the commercial market. “We’ve developed several prototypes. We are at our second generation prototype. We did the testing and this second one is twice as efficient as a three blade turbine and in terms of manufacturing is at least 50 percent cheaper,” Labaied told EcoSeed. Once a manufacturer is found, Saphon believes that it will take around 18 to 24 months to get the first commercial device on the market.