Many blade manufacturers can’t afford the hefty investment, says Johnson. Others have a hard time justifying the expense. “Despite all the advantages of automation, this is an industry dominated by hand layup that’s struggling to rationalize an investment in capital,” says Kappesser.
Hand layup reigns, in part, because of talented employee teams. “Through proper training in the basic concepts and a lot of repetition, they are very good at what they do,” says LaFrance. “A well-trained team can fill a mold in an amazing amount of time. They’re like a football team: They know exactly what each other is doing, and they anticipate each other’s behavior.”
Team sizes vary at MFG, but up to 12 people work simultaneously in the molding operation. At peak performance, it takes 24 hours to turn over a mold between the time it’s prepped and when the blade is pulled out.
For GE Energy, achieving the best production rates is crucial. “In the blade world, you can apply a lot of labor very rapidly to put materials in a mold,” says Johnson. “That equation hasn’t been cracked from the automation perspective.”
Part of the quandary is the blade structure itself. There are several hundred individual pieces of reinforcing fabric, mat and core. The tip of the blade in the basic shell may be as simple as a layer of balsa or foam core material between two layers of biaxial fabric. But the root of the blade could have a hundred layers of biaxial, unidirectional and multi-axial fabrics in a solid laminate, says LaFrance. The remainder of the blade varies.
“A blade is a very complicated composite part,” says LaFrance. “Getting the core materials, reinforcements and other things like lightening protection into the blade positioned in the right place requires a lot of human intervention at this point.”
Automation wouldn’t signal the end of skilled labor, rather a shift in competencies. “If blade automation technology becomes available, you will see a change in the workforce at blade suppliers,” says Johnson. “They will go from labor-intensive activities to technically-intensive ones.” Employees of the future will need to know how to program, operate and inspect sophisticated computer-controlled equipment.
Advantages of Automation
Though challenges to automation exist, the potential benefits are significant: greater process consistency, improved blade quality, increased productivity and reduced waste. “If you take out the human element, you take out the variability,” says LaFrance. “You speed the changeovers and ultimately you make a blade that’s cheaper than we can make now.” That’s good news for the 400-plus companies in the U.S. that produce components for the wind industry.
In 2010, more than 5,000 MW of wind projects were installed in the U.S., according to AWEA. Last year, that figure increased to 6,810 MW. For those numbers to continue to rise, automation must play a key role.