A wind powerhouse in Attleboro?

Taking on a major obstacle to mass adoption of wind energy, a startup company based in Attleboro is working to develop a system that can produce electricity from turbines even when the wind isn’t blowing.
General Compression Inc. hopes to commercialize a wind-power system that compresses air and stores it, then decompresses the air and converts it to electricity on demand. The novel technology is attracting interest from investors, who provided the company more than $8 million in an initial round of funding in April.
With eight employees and plans to hire another seven by September, the company plans to seek $30 million in another round of funding to build three full-scale, 1.5-megawatt turbine prototypes, said Michael Marcus, General Compression’s president.
Marcus and his brother, David Marcus – General Compression’s CEO – co-founded the company following extensive experience as partners, shareholders and investors in other wind energy developers, including Ridgeline, Midwest Renewable, NedPower, Greenlight, Windworks, and the Clean Power Income Fund, and in several wind energy technologies, including Princeton Power, Fallbrook Technologies and Mechanology.
The brothers believe they have a technology that will spur development of wind farms by enabling operators to charge more for their product by storing wind energy when demand is low and selling when demand increases.
General Compression’s system uses a revolutionary compressor inside the wind turbine that compresses air to extremely high pressure, then sends it down the tower and stores the air in an underground pipe system interconnecting all the turbines in a wind farm. The compressed air can also be stored in underground caves and depleted mines and aquifers.
When needed, the pressurized air is released into a power plant of expanders and generators that produce electricity even if the wind isn’t blowing. For example, if the wind is blowing at night, the wind farm can store the energy generated from the turbines and convert it to electricity in the morning.
“In essence what’s happening is we’re putting compressors up in the [turbine], instead of electric generators, and we will be making high-pressure compressed air … and running that down the tower and pipeline and then connecting that up to other pipelines that we’ve buried underground,” Marcus said.
Marcus spoke with Providence Business News on his cell phone while traveling from Washington, D.C., where he met with top officials from the U.S. Department of Energy to solicit support for General Compression’s plan to possibly develop wind turbines.
He said the company will pursue one of two paths depending on how things progress in the next two and half years.
The company is prepared to be a stand-alone manufacturer of turbines, but could also choose to license its compressor array and control system technology to other manufacturers, Marcus said.
“It could become the ‘Intel chip’ inside of other manufacturers’ turbines, if they want to license the technology from us,” he said.
General Compression aims to have its turbine prototypes up and operating by the end of 2009, Marcus said. In June, the company hired Rahul Yarala as its chief technology officer to lead the development of the turbines. Yarala previously was director of engineering at Clipper Windpower Inc., where he was responsible for all mechanical design aspects of Clipper’s Liberty 2.5 MW wind turbine from concept to operation.
“Rahul’s experience in taking wind turbine technology from concept to operation will be a tremendous asset to General Compression,” David Marcus said in a news release.