A new wind-power machine has been inspired by a centuries-old idea: Persian "wind catchers."
Windation Energy Systems, a Menlo Park, Calif.-based start-up, has developed a wind appliance that looks more or less like the modern heating and cooling equipment you see on flat corporate building rooftops.
There's a 8-by-8-foot frame around a 10-foot-high cylinder. Wind blows in the top and is directed to the bottom where the wind turns a turbine to make up to 5 kilowatts of electricity. A single unit wouldn't generate enough power for an entire office building but could offset a significant portion, the company says.
Windation CEO and founder, Mark Sheikhrezai, who is originally from Iran, said he was inspired by ancient Persian buildings that use air currents and reservoirs of water to cool buildings. Using differences in air pressure, these wind catcher buildings create a steady flow of air without any mechanical devices.
Although Windation's wind appliance does draw air from the top like these buildings, Sheikhrezai said he used his expertise in centrifuges and rotors to manipulate the movement of the wind to generate electricity.
The overall design breaks with that of other small wind turbines, which tend to look a lot more like wind turbines.
Aerovironment's wind turbines, now installed in a few locations, are essentially miniature wind turbines perched on the edges of buildings. Another approach is the vertical axis turbine from Mariah Power.
Sheikhrezai said one of the biggest advantages of Windation's appliance is its shape and ease of installation. Since all moving parts are contained, there isn't potential danger to birds, bats, or people, he noted.
Financially, an investment in a 5-kilowatt appliance, which comes with its own inverter, recoups the installation cost of $45,000 to $50,000 in five to seven years, he said. Depending on the wind or sun resource, a wind machine could deliver a quicker payback than installing a solar array on commercial flat-top roof, he asserted.
The units will work well with what's called "dirty wind," or gusty, inconsistent wind, Sheikhrezai said.
"Cities like San Francisco, Chicago, Boston, Miami, Cleveland--places you wouldn't think--are all good wind places," he said.
The company is set to install one unit at the Palo Alto Medical Foundation in California and plans to begin manufacturing more units for delivery in February. It then intends to ramp up manufacturing in the following two years. The product will be made in old windmill factory in Nebraska.
Windation, which formed last year, is looking to raise up to $5 million in the next two years and then raise another $20 million for further expansion, Sheikhrezai said.
Small wind turbines are poised for more growth in light of the recently passed economic recovery act. The federal law includes a tax credit of up to $4,000 for small wind turbines, which the mayors of New York City and San Francisco have endorsed for city buildings.