The next generation of turbine wind blades may someday come from natural fibers and plant-based plastics from soybean, linseed, and other vegetable oils, instead of oil-based polymers. Here is the story from Fast Company:
A world powered by wind sounds super clear, until you start having to replace football-field-sized turbine blades. But what if they were made of something easy to recycle, like plants?
There’s nothing to burn. No ore to mine. No coal trains snaking from Wyoming to Midwest power plants. But wind power has its own pollution problem looming.
Last year, one third of new electric capacity in the U.S. came from wind, reports the DOE, and it’s growing quickly. All of the new U.S. generating capacity in September 2012 came from wind and solar, says the Federal Energy Regulatory Committee, and the U.S. now relies on wind for 4.43% of its total generating potential. And there’s plenty of room to expand: Industrialized nations–Denmark (29%), Spain (19%), and Germany (11%)–are building heavily wind-driven energy grids.
The problem comes when all of those wind turbines need to be replaced. Scandinavia, among the first to adopt wind into its energy mix, is on the leading edge of this problem: “As the wind becomes a central part of energy supply, a huge waste problem is growing with similar speed,” reported Denmark’s major business newspaper Dagbladet Børsen in 2011.
While wind power looks self-contained–a field of towers, white fiberglass rotors, and the breeze–the massive fiberglass and carbon-composite blades eventually have to be decommissioned and replaced. Mechanical engineering Christopher Niezrecki of the University of Massachusetts Lowell’s Wind Energy Research Group estimates the U.S. will have as many as 170,000 wind turbines by 2030 (about 20% of the country’s installed capacity) translating into more than 34,000 trashed blades per year; globally, the figure may be as many as 170,000. Since each blade can stretch the length of a football field and weigh 18 tons, that’s a lot of unplanned waste.
To prevent this avalanche, the National Science Foundation (NSF) is funding Niezrecki and the University of Wichita to find biological-derived materials for biodegradable blade materials that replace carbon-fiber composites and petroleum-based epoxies, the current industry standard. As today’s materials cannot be easily recycled, most used blades are cut or ground up for incineration and burial in landfills and roads.