Trending Turbine Technology
The use of wind turbines continues to change the landscape of energy development around the world. They are dotted along the plains of Texas, along the shores of Europe and hoisted on city and suburbia businesses alike. But as turbines become increasingly technologically advanced, what trends are emerging in their manufacturing, and how do composites fit in to this upward drive for lighter, larger and more efficient turbines?
Focused primarily on utility grade, horizontal axis wind turbines, Totaro & Associates of Santa Barbara, California, a consulting firm that works with renewable energy companies to develop new products and technologies, collected wind turbine patent filing data and broke these filings down into current or future relevancy. Analysis of the data gives a glimpse into current trends and in what direction those developments are leading turbine evolution. The group’s results concluded that there are six areas of emerging technology. Among them are turbine reliability, weight reduction, transportation, fleet management, performance optimization and creating a “grid friendly” system.
According to Philip Totaro, Principal at Totaro & Associates, the blades, generators and electrical systems of a wind turbine have historically been the largest areas of focus because ultimately the efficient conversion of mechanical energy into electrical is the overall intent. “It must be noted that these three areas have been most problematic for manufacturers when it comes to component reliability, so they have garnered a great deal of attention in terms of innovation to improve quality and performance,” he says.
Similar to the automobile industry, the goal of wind turbine manufacturers is to lessen the component loads and decrease part count. “Right now there is a perceived reliability issue with three-stage gearboxes. They require regular maintenance and have been prone to reliability problems. Some in the industry suggest that we replace of these gearboxes, which function is to up the RPMs (revolutions per minute) of the wind turbine rotor, with a generator that is directly connected to the blades. While that sounds great because you’re removing a component with a reliability problem and reducing the number of components that could potentially fail, there are other issues created such as stray current mitigation torque regulation and the risk associated with a new overall design paradigm of a direct drive generator,” says Totaro. “Permanent magnet generators are a popular option for direct drive, but acquiring the rare earth metals required to make them is becoming more costly. No one has figured out the end result yet. There are a lot of people that believe gearbox elimination is best, others say that with the 30 years of data the industry has collected on three stage gearboxes, the industry can fix the problems.