Green energy: Rooftop unit generates electricity in moderate wind
| Windcube is said to produce the same amount of energy as a traditional (50 ft dia) turbine in a 22x22x12 ft framework.
Green Energy Technologies LLC launched its WindCube, a 60 kW rooftop wind turbine designed for on-site power generation by commercial and industrial power users in urban and suburban locations. The turbine, which captures and amplifies the wind, fills a previously unmet need for wind turbines that can be placed into service in a very small footprint and take advantage of the nation’s net metering laws. [
The turbine is available as a single (60 kW) or dual (120 kW) system, and in rooftop or tower-mounted designs. The product is modular to satisfy a customer’s electrical requirements, and produces the same amount of energy as a traditional (50 ft dia) turbine in a 22 x 22 x 12 ft framework. Expected users include industrial companies, commercial office buildings, big-box retailers, college campuses, and electric users in remote locations.
The WindCube features a patent-pending design that relies on the wind tunnel effect known in physics as the Bernoulli Principle. While the rest of the wind industry generates energy through the use of freestream wind, the WindCube captures and amplifies the wind, which produces more kilowatt hours (kWh). As the wind comes into the WindCube shroud, it becomes concentrated, creating increased velocity and, in turn, more power, the company says. Because of the amplification effect, the WindCube can capture wind energy as low as 5 mph.
The WindCube generates electricity by running its motor backwards using an impeller (the opposite of a propeller), eliminating the need for a gearbox. This lowers the cost of ownership, because the gear box is the source of most of the maintenance problems and failures on conventional wind turbines.
The American Recovery and Reinvestment Act of 2009 federal stimulus law reportedly contains a provision that allows buyers of “small wind” systems (up to 100 kW) an uncapped investment tax credit of 30% of the total installed cost for systems placed in service between now and 2016.
The American Wind Energy Association predicts the federal subsidy could help the small-turbine market grow by 40% to 50% annually, a boost that would parallel the growth of the U.S. solar photovoltaic industry after a similar 2005 initiative. Most states provide some form of applicable renewable energy incentive. Ohio, for example, offers a tax rebate of 40% (capped at $200,000) of the overall project cost on facilities served by the state’s investor-owned utilities.