SheerWind’s Invelox system, which is being demonstrated in Minnesota, funnels low-speed winds through successively smaller chambers to augment the speed. The wind then turns turbines to generate energy. SheerWind
New wind-intake system captures wind and speeds it up—even in calm locales—to generate energy.
April 29, 2014—A small company based just outside of Minneapolis is hoping its novel take on capturing wind energy will catch on, helping to bring power to remote areas with limited energy infrastructure.
SheerWind’s Invelox system does away with the traditional design of harnessing wind energy with massive, tower-mounted turbines, and instead uses a multidirectional, wide-mouthed intake system to funnel even the lowest-speed winds toward a power-creating turbine at ground level.
The company’s immediate goal, says spokesperson Carla Scholz, is to have several units of different sizes up and running both domestically and abroad by this time next year.
The energy production capability of these installations ranges from 50 kW to “a couple of megawatts,” says Daryoush Allaei, Ph.D., P.E., the company’s founder.
Scholz says plans are in place for a pilot installation of the technology in Royalton, Minnesota, about 20 mi north of St. Cloud near the Mississippi River. Royalton has made a $25,000 down payment for the system, but other start-up costs will be funded by SheerWind and its investors, who stand to recoup their investment by selling any power generated by the system that exceeds what the town can use. Royalton is tiny—slightly more than 1,200 residents—but it should prove to be a valuable testing ground because wind speeds are often below 10 mph. If the Invelox system can turn around those low wind speeds and magnify them by a factor of three or four by using the Venturi effect (a process of funneling air through a number of smaller chambers to augment its speed), it could prove the system to be financially viable both for the town and the firm. The goal is to have the system running by late 2014.
The 200 kW unit, which would sell for close to $700,000, will be about the size of a municipal water tower, including a 35 m diameter intake and 6 m diameter turbine. The Minneapolis office of the London-based global engineering firm AMEC and the Minneapolis office of Clark Engineering Corporation worked with Allaei’s energy-efficiency company, QRDc, from which SheerWind spun off, to develop the design, which will use a combination of concrete, rolled steel, and a framed fabric. The energy-generation and management components—blades, turbine generators, and controllers, for example—will be purchased from vendors specializing in those fields, and then local contractors will be hired to build and assemble the unit.
Abi Assadi, Ph.D., P.E., M.ASCE, the president and chief executive officer of Clark Engineering—who at one time collaborated with Allaei on vibration-reduction systems for hospitals with MRI machines—says his firm intends to use its expertise in building both traditional wind towers and elevated water tanks to help SheerWind bring the overall price of the Invelox installation down. In the last month, Clark has been attempting to streamline the system’s design in two ways: by making fiberglass molds for the main structural components of the system so it will not require expensive field fabrication, and by framing the Invelox around a water tank so that future installations would include both water storage and wind-energy components.
“It would be connected to our main structural system, more like a water tank, with six-sided columns and a tension-bracing system,” Assadi says. “It looks okay aesthetically, [and] it’s very simple to build, and in that way you can save on the structural system, and it’s replicable. You can go from 200 to 400 to 500 kW by just increasing your bracing system.”
Additional attention is being paid to the system’s foundation. For example, elevated water tanks are immediately more cost effective when built using a ring foundation compared to those built on a concrete slab, so this is being considered for the test project.
Assadi adds that the system has been designed so that the working parts are at ground level; if a turbine were to go down, the repairs or replacement would take place at ground level, another advantage over tall wind towers.
Royalton mayor Andrea Lauer says that while her city is small, the Invelox installation could make a big impact—not only by lowering the town’s energy expenses, but by making drivers on nearby Interstate 10 take notice. Lauer, who took office eight years ago, says she’s made other improvements in the city’s energy consumption: the City Hall has solar panels on its roof, traffic lights were changed from incandescent to light-emitting diode bulbs, and the city initiated a lamp replacement program ultimately resulting in a 39 percent reduction in energy spending. Wind energy has been on Lauer’s mind for years, she says, but her city just isn’t blustery enough to exploit traditional systems. “This is something that’s the next generation of wind technology,” she says, equating it with smart phones, an invention unimaginable just a few decades ago.
While the technology works on SheerWind’s test bed, the Royalton project will represent the first time that it will be installed under real-life conditions. “I know many people have looked at things like this [before], and as far as I know, nobody has been able to make it [work],” says Anthony Ellis, a senior research fellow at the University of Massachusetts-Amherst’s Wind Energy Center. He sees the potential for the system to become valuable in locations around the world where not only are the winds calm, but access to other forms of power is limited or too expensive. In those cases, the system would be useful if the technology is affordable.
Scholz says a 200 kW system would produce more than 1.2 million kWh per year, working out to an energy production cost of about $.05 per kWh. Other systems that have a similar cost, but less capacity, produce energy that’s twice as expensive, she explains.
While projects like the one scheduled for Royalton and a second pilot test recently announced in Dubai should help to get SheerWind off the ground, Allaei’s ultimate goal is to see his company deliver power to parts of the world in which keeping the lights on is a daily challenge. “If it’s proven what we claim is true, from a company perspective, it would open the door for a larger capital infusion and bigger customers,” he says. “To grow the company faster, that would help us reach our goal of providing power for all people, so they can set their own destiny. Clean water, food, [and power]—those are the basic ingredients for setting your own destiny.”