Contrary to popular belief, taking a piano to a fourth-story walk up apartment in New York City may not be the toughest moving job. Consider the wind turbine. The stiff fiberglass blades of the largest turbines span half the length of a football field. Moving them from the factory to the wind farm requires custom cranes, oversize rigs, hours of careful route and traffic planning, and expert drivers to execute precarious turns. What if you could do away with all that and also eliminate the million-dollar molds used to make them for good measure?
Blowing in the Wind: A section of a wind blade depicting a new manufacturing concept that covers the blade with a “tensioned” fabric. This new approach could significantly reduce production costs.
Scientists at GE Global Research, Virginia Tech, and the National Renewable Energy Laboratory have started working on a new blade design using fabric wrapped around a skeleton of metal ribs resembling a fishbone. GE estimates that that the new design could revolutionize the way wind blades are designed, made, and installed, cut blade costs by 25 to 40 percent. “We are weaving an advanced wind blade that could be our clean energy future,” says Wendy Lin, a GE engineer and leader of the three-year project, which the government’s Advanced Research Projects Agency (ARPA-E) is backing with $5.6 million. “The fabric we are developing will be tough, flexible, and easier to assemble and maintain” than fiberglass, Lin says.
The use of fabrics as a tool to lower weight is not a new idea. Aircraft manufacturers used them to cover the wings of fighter planes in World War I. GE already makes rugged fabrics for wind protection and architectural design.
But Lin says that the new high-tech fabrics, which are based on fiberglass, will help spur the development of larger, lighter turbines that can capture more wind at lower wind speeds. Current technology makes it hard to produce turbines that have rotor diameters exceeding 120 meters (nearly 400 feet) because of design, manufacturing, assembly, and transportation constraints. GE’s new fabric-based technology would all eliminate these barriers.
Experts estimate that in order for the U.S. to generate 20 percent of electricity wind, the currently installed wind blade area would have to grow by 50 percent. Fabric blades can make this possible. “Developing larger wind blades is the key to expanding wind energy into areas we wouldn’t think of today as suitable for harvesting wind power,” Lin says. “Tapping into moderate wind speed markets, in places like the Midwest, will only help grow the industry in the years to come.”