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The higher up in the air you go, the faster wind travels - so naturally the further from the ground a wind-turbines gets, the more efficient it can be. Thats why the idea of a flying wind-turbine is a such a win-win (or win-wind) proposition. Combining wind power with floating blimps, Selsam has been hard at work expanding the horizons of alternative energy with a revolutionary new breed of SuperTurbines that promise to take wind power to new heights.

Resembling a field of wind-swept reeds swaying on the horizon, these floating wind spires boast an ultra-efficient design that flexes with the wind, taking advantage of air currents along the length of their shaft to generate electricity. Selsam’s prototypes produce 6000 watts in 32.5 mph winds - six times more power than a similarly sized seven foot single-rotor turbine can produce. The turbines can be easily deployed by land and by sea, and their effectiveness can be amplified even further via an air-born blimp.

We’re currently at a bottleneck in the wind turbine pipeline, with GE reporting that it is unable to make turbines fast enough to meet demand. It’s no wonder, since the largest turbines have a propeller size that surpasses the wingspan of commercial airliners and require an intricately machined gearbox. This amounts to a time and resource-intensive engineering and assembly process that has production struggling to deliver on a $12 billion backlog of orders.

Selsam’s SuperTurbines offer an innovative approach to the problem with a scaled-down system of multi-rotor stalks that are extremely versatile, more efficient, and cheaper and easier to produce than than large lumbering windmills. The design relies upon economy of scale to maximize efficiency, employing multiple rotors along a lightweight, flexible shaft that allows it to shift and move with wind currents. Since the turbines rotate at higher rpms than traditional turbines, a small and light direct-drive generator can be used instead of a hulking gearbox.

Selsam’s most recent designs are optimized for sea deployment and consist of a rotor-studded shaft stemming from a floating base that is anchored to the ocean floor. The system is designed so that turbine’s base rotates similarly to the human spine, thus the turbines won’t twist and spin out of control. In an ingenious answer to stormy weather, the turbine’s base can fill with water, submerging it safely beneath the ocean’s surface.

In addition to producing energy, the multiple rotors act in unison to keep each stalk afloat; if you’re in need of a visual metaphor, Selsam’s website supplies them in spades: “Like a flock of geese, each rotor favorably affects the next in line. Like a set of louvres, the tilted rotors pull in fresh wind from above, deflecting their wakes downward to insure fresh wind for succeeding rotors and, like a stack of kites, to add overall lift which helps support the driveshaft against gravity and downwind thrust forces. The rotors act as gyroscopes or spinning tops, stabilizing the driveshaft where they are attached.”

When we recently wrote about Sunhope’s solar balloons, many people suggested that they take advantage of wind energy as well. It turns out that Selsam is one step ahead of the game with this exciting technology. Let’s just hope they find a way to negate the turbines’ ominous implication as potential bird blenders.

Via : Ecogeek.org

How to keep the lights on when all is still and the local windmill won’t budge? A small Norwegian island testing a way to store wind-generated energy for calm days may have found the answer.

The tiny, windswept island of Utsira, situated off Norway’s southwestern coast, is home to what is said to be the world’s first full-scale system for cleanly transforming surplus wind power into hydrogen.

Perched atop a 40-metre-high wind turbine on a perfectly windstill day, technician Inge Linghammer explains that at times like this or on days when the gales whipping the unsheltered island get too strong the windmill shuts down and stops pumping out power.

“You need to have back-up power when this happens,” he says, nodding towards the motionless blades.

On a good day, the island’s two wind turbines, planted on a small hill overlooking several red-painted wooden houses, produce more energy than the 210 people living here can use.

When they are down however, most of Utsira, which measures only six square kilometres, is furnished with electricity from the mainland.

But 10 households receive clean, wind-generated electricity regardless of the weather conditions, thanks to a pilot project launched here in July, 2004 making it possible to store wind power by transforming it into hydrogen.

Surplus wind-generated energy is passed through water and, using electrolysis, the hydrogen atoms are separated from the oxygen atoms that make up water molecules.

The hydrogen is then compressed and stored in a container that can hold enough hydrogen gas to cover the energy needs of the 10 households for two windless days.

“Utsira has more than enough wind power to be self-sustained … but the problem arises on a day like today when there is not enough wind,” explains Halgeir Oeya, who heads up the hydrogen technology unit at Norwegian energy giant StatoilHydro, which is running the project.

“This system allows us to deliver power with expected quality and reliability,” he says, standing next to the large metal electrolyser box baking in the spring sun.

Combining renewable energy and hydrogen, he says, makes most sense in secluded areas like the numerous islands lining the European coast or in remote Australian communities, which until now have been heavily dependent on carbon dioxide-spewing diesel fuel provided by a constant flow of truck convoys.

Islands like Utsira have long been considered ideal laboratories for renewable energy due to their total dependence on outside energy supplies and their access to powerful wind energy.

Oeya boasts that the people participating in the Utsira test project have no restrictions on how they use power, switching on the lights, dishwashers, television sets and stereos without a thought to how the wind is blowing.

And amid growing alarm over greenhouse gas-promoted global warming, they can do so with a clean conscience, he says, pointing out that “the only emission is oxygen.”

Producing and storing energy this way however is still, nearly four years after testing began, far more expensive than the hydraulic power produced on Norway’s mainland.

StatoilHydro has no intention of building up the system to compete with large-scale energy production, but even making it competitive in the small, remote communities far off the grid that make up its target market remains years off.

“This is not a commercial project as it stands,” Oeya acknowledges.

“We must have a bigger scale in order to compete … and this will take a number of years,” he says.

Utsira mayor Jarle Nilsen is nonetheless ecstatic about the system and its effects on his small island community.

“This is a fantastic project that has been good for Utsira,” he says, pointing out that initial concerns about noise levels and birds getting caught in the turbines had been laid to rest.

“We haven’t found a single dead bird,” he says.

Most importantly, the system was helping nudge his Utsira towards its goal of zero emissions within the next decade and had become a major tourist attraction.

“The tourists go over to the lighthouse first, but then they go to look at our windmills. They want to see the world’s first full scale wind and hydrogen project in action,” he says proudly.

Alternative-energy firm starts testing its innovative airborne wind turbines

The Canadian startup Magenn Power has started testing its airship-based wind turbines. The Magenn Power Air Rotor System, or MARS, consists of a blimp-like device that is tethered to the ground, and rotates about its horizontal axis in the breeze. This action generates electrical energy, which is sent down the tether to a transformer, and eventually routed through to the grid.

Magenn says that it’s air-based turbine system will surpass all the other wild airborne wind-power schemes out there in terms of cost, efficiency and more. The advantage over ground or sea-based turbines is that the blimps, floating at high altitudes, should be able to tap into stronger, more consistent breezes. Depending upon the size of the model, it should produce between 10 kilowatts and several megawatts of power. Of course, that’s assuming that it works.

The company recently tested a scale version in a massive indoor facility, and plans to move outdoors for testing soon. The first working versions will probably be at industrial sites, with commercial versions to follow. More on how it works here.

Via MetaEfficient