Wind energy is still relatively new in the United States, but there's a big problem ahead for the industry — what to do with the 170-foot, 22,000-pound blades when they need to be taken down and replaced.

Many landfills won't take them, and the fiberglass materials are difficult to recycle.

Here & Now's Peter O'Dowd asks Karl Englund, an engineering professor at Washington State University, about the industry's attempts to the solve the problem before it becomes a crisis.