If you’ve ever walked through a skyscraper-laden city on a windy day, you know how big buildings can intensify the gales, creating wind tunnels that accelerate the gusts so that they blow off hats and flip up skirts. Now a 3-year-old Akron, Ohio-based startup called Green Energy Technologies wants to use that same wind-tunnel effect to generate small-wind power more efficiently.
The company has developed a 60-kilowatt, five-blade turbine that comes with what it calls a shroud, which looks like a sort of shallow metal funnel. The shroud creates a wind-tunnel effect in front of the blades, amplifying the wind velocity by a factor of two — so that a 5 mph wind that enters the shroud reaches 10 mph by the time it hits the blade — allowing the system to harness even low-speed winds and ultimately produce more electricity from them.
Green Energy claims its WindCube, unveiled last month at the Windpower conference in Chicago and intended for commercial and industrial buildings in urban and suburban locations, can generate power from winds as slow as 5 mph. Over the course of a year, Green Energy says the system can generate 100-130 megawatt-hours — about the same as a traditional 100-foot-tall turbine with blades 50-60 feet in diameter — in places with winds that average 12 mph, says Mark Cironi, president and founder of the company. For context, 12 mph is fairly windy, and is the average wind speed in cities such as Boston, Lubbock, Tex., Fargo, North Dakota, Oklahoma City and Wichita, Kan.
The WindCube boasts a gearbox-free design to reduce maintenance and increase reliability, and rotates into the prevailing wind so that it can generate electricity from wind coming from different directions, according to the company. And because of its cubed design, installers can put mesh over it to keep birds and bats from flying into the blades in migratory or other environmentally sensitive areas, Cironi said.
The small-wind industry is seeing increased activity as the result of the stimulus package, which in February made small-wind projects eligible for a 30 percent federal tax credit and allowed customers to opt for grants instead of credits, as well as various state incentives. The American Wind Energy Association last week forecast that the U.S. small-wind industry, which grew 78 percent to 17.3 megawatts of new capacity installed in 2008, will grow 30-fold over the next five years.
Green Energy is an example of this growth. The company has completed its first commercial installation on an industrial building owned by battery firm Crown Battery, Cironi told us Tuesday. Crown Battery received a rebate from the state for the project and is eligible for federal incentives that — taken together — will cut its project cost by 70 percent, he said. The WindCube price tag is $279,000, plus installation. Green Energy says that with federal and state incentives, customers can expect to see a return on their investment in as little as 2-3 years.
The company already has hundreds of orders in place and expects to expand quickly, adding at least 200 jobs in the next year, Ciron said. Green Energy has been testing the wind at a number of big-box retailers and grocery stores so that it will be ready to install the WindCubes as soon as they are available. And Green Energy’s factory is already fully tooled up and ready to begin building 32 blades a week starting at the beginning of July, Cironi said, adding that the company is in the process of buying out the partner that set up the factory and taking ownership of the building.
Green Energy is targeting the gap that it sees between small residential wind turbines and large utility-scale wind turbines. Cironi says the WindCube’s shape and small size — the blades are 15 feet in diameter and the whole system measures 22x22x12 feet — enables it to be installed on roofs. That differentiates it from competitors such as Southwest Windpower, which makes ground-mounted turbines.
So far Green Energy has raised $1.5 million from family and friends for R&D, and, more recently, another $2 million in equity funding from Ohio-based Roth Bros. Inc., a building services and construction company, to begin production.