Rather than build farms of towering wind turbines in rural areas, some companies are designing "micro," or small-scale, turbines that fit on top of buildings. The idea is to generate electricity from wind in urban or suburban settings.
"We want to integrate these small wind turbines on buildings in plain sight," said Paul Glenney, director of energy initiatives at Monrovia, Calif.-based AeroVironment. "We think this can really communicate the generation of clean electricity."
A handful of "micro" wind turbine companies are trying to bring small-scale wind power generation to urban and suburban settings.
On-building wind turbines are still an emerging technology, but they could fill a viable niche among different products for generating energy.
In their pitch for the technology, the companies are going beyond satisfying the AeroVironment, Aerotecture and a handful of other businesses are marketing their turbines not just as power generators, but also as attractive additions to existing structures.of energy.
Right now, giant turbines built by the likes of GE Energy and Siemens are still the norm in the wind power industry, and on-building versions are rare. Newcomers are trying different tacks to break into the market. While some such as Clipper Windpower are producing entire devices, others are focusing on providing specific components of a turbine.
"We're tracking over 20 different emerging wind technology companies in our proprietary deals database, and that list keeps growing," said Robert Day, a partner at Expansion Capital Partners which specializes in .
Overall, the wind industry is booming, experts said. The American Wind Energy Association said that last year 2,500 megawatts of new generation equipment were installed in 22 states, valued at $3 billion.
AeroVironment, which is perhaps best known for its technologies, has a project under development from its Architectural Wind energy technology division.
The turbines look like large fans in square housings. They are specifically designed for placement on the top of steel-reinforced, flat-roofed commercial buildings such as a warehouse or "big box" retail store like Home Depot, Glenney said.
The turbines can be lined up next to each other to aggregate power generation, and the fans will spin even in a very slow wind of a few miles an hour.
The company has set up a few beta sites to test various factors, including its cost-effectiveness, the amount of noise it generates, and the potential impact on birds and bats (the turbines have a grate on both sides).
AeroVironment has not yet decided whether to commercialize the products. But in presentations with potential customers, the company has gotten a good reception, Glenney said. Business owners and municipalities are eager to find sources of clean electricity for a variety of reasons, including concerns over global warming and dependence on oil from unstable parts of the world.
"Lots of companies just want to reduce the footprint that a business leaves" on the planet, Glenney said. "And they want to educate their stakeholders--their customers, their pupils--on these issues."
Chicago-based Aerotecture is taking a similar "architectural" approach to wind power generation, although with a substantially different design.
Invented by University of Illinois professor Bil Becker, the company's Aeroturbine product uses a helix-shaped turbine placed inside of a cylinder. The turbines, which are 10 feet long, can be placed in many positions and take advantage of variable wind, according to the company.
"It's not fussy about gusty or turbulent winds. It's very amenable. It's the microclimate of the building that you have to look at," said Lesleigh Lippitt, co-founder of Aerotecture.
The company, which is in the process of commercializing the product, is negotiating with Chicago city officials over an installation at the Daley Center, which would set Aeroturbines at the top of the 650-foot building, she said. Other placements are under discussion, including underneath San Francisco's Golden Gate Bridge, Lippitt said.
Other companies building similar micro wind products for urban or suburban areas include Finland's Windside, and the U.K.'s Windsave and Renewable Devices. There's also a product line called Urban Turbines, from Dutch company Ecofys.
Also on the market are several turbine products, such as Southwest Windpower, designed for remote homes or boats.Mix and match
Expansion Capital's Day said that small-scale wind technologies have a viable role in the bigger picture of power generation.
Placing a 300-foot high turbine in downtown San Francisco is problematic. But distributed, or on-site, electricity generation systems can help customers get around the transmission bottlenecks and reliability problems of the wholesale electricity grid, Day said.
He added that even small-scale turbines are not immune to the challenges that the overall wind industry faces, such as concerns over noise and cost efficiency.