Sustainable Systems: Designing a Windmill for the 21st Century
Wildly fluctuating energy prices, environmental concerns and geopolitical pressure have leaders from Washington to Harrisburg calling for the development of alternative energy sources. Terry Sankar, CEO of Pittsburgh-based Sustainable Systems, sees change in the air-quite literally.
“Wind is everywhere. So why don’t you see windmills everywhere you look?” asks Sankar, an engineering Ph.D. candidate at Robert Morris University, who has developed a vertical axis windmill that promises low costs, high safety and extensive flexibility in size and uses.
Wind power generation has more than quadrupled globally between 2000 and 2006, but still makes up just a small fraction of global energy production.
Power, Power Everywhere
The turbines on a typical windmill are oriented on a horizontal axis, like an airplane propeller on a pole. Sankar’s vertical axis windmill is oriented up-and-down and resembles a giant eggbeater-which gives it dramatic advantages over traditional windmill technology. For one, the orientation of the blades would allow the technology to be installed on existing poles, towers and rooftops just about anywhere, many places where it may not be possible, or practical, to deploy conventional systems.
“Drive down the highway or look in parking lots, and you see poles everywhere,” says Sankar. “Imagine each one as a little electrical power plant, quietly and unobtrusively spinning out clean energy from the wind.”
The basic design has been around since the Persians used it around 500-900 A.D., but Sankar’s technology is solidly 21st century in its approach. Early testing indicates the system can produce electricity for about 65 percent of the cost of traditional systems.
“Imagine if each and every Wal-Mart, McDonalds and Whole Foods were energy independent,” he says. “Placing our system on their roofs, parking lots and utility poles could make this a reality.”
Funding and the Future
Ben Franklin Technology Partners gave Sustainable Systems a $25,000 University Innovation Grant-funds Sankar used to purchase highly sophisticated analytical software to virtually test and refine his designs in the lab.
“Without BFTP’s support, I would not have gotten anywhere at all,” he says. Sankar is also working with BFTP to refine the company’s business plan. “They continue to be essential in moving this technology from the lab to the marketplace.” The system should be commercially available within the next two years.
Sustainable System’s turbine design can function in a wide variety of sizes and environments. According to Sankar, they can be made at the 1-3 megawatt public utility scale-or so small they can go into mine shafts to provide electricity to communications equipment for miners. Sustainable Systems is in the process of installing a 60-foot prototype at Seven Springs Resort in southwestern Pennsylvania, expected to be capable of generating 100kw of electricity. The ski resort-with its high energy consumption and ample supply of wind-is an ideal testing ground.
“In addition to powering snowmaking operations, which have quadrupled in costs over the past five years, places like Seven Springs are building lots of condos,” he adds, noting that this particular prototype could power 30 homes. “A traditional 200-foot wind turbine grinding through the night wouldn’t be appealing at all.”
Surpassing Old Technology
Current horizontal wind turbines are extremely efficient at what they do, but suffer from several drawbacks. In addition to being expensive (and becoming more so), a megawatt system costs $1 million plus to build and install. They require large tracts of dedicated land, create significant noise, have limited aesthetic appeal and-most limiting of all-must constantly face the wind to produce electricity.
“If the wind blows from the east, and the turbine faces south, it’s useless,” says Sankar. “In fact, on small wind farms, these massive turbines may be turning only 40 percent of the time due to low wind or wind coming from the non-facing direction.”
For all its advantages-size, cost, efficiency-the vertical axis design never took off because of two key factors-tradition and airplane technology.
“As airplane technology became more sophisticated, the technology was rolled into making very efficient air power turbines,” Sankar notes. “But even though these systems are highly sophisticated, our system provides very clear and decided advantages.”
Sankar believes he’s solved the major problems faced by earlier vertical axis designs and in the process made them even more efficient. “We may have, in effect, perfected the modern-day windmill.”
Keynotes June, 2007
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