The wind energy industry is growing in the United States, and that means the country is going to need tens of thousands of new composite wind blades in the next decade. In 2019, it took more than 60,000 wind turbines to generate 109,919 megawatts (MWs) of electricity in the United States, Guam and Puerto Rico, according to the American Wind Energy Association (AWAE). Between projects already underway or currently in the final planning stages, AWAE projects another 44,000 MWs of wind power will be added over the next few years.

The hitch is that manufacturing a wind blade is currently a time-consuming and labor-intensive process. For example, GE Renewable Energy reports that it takes two days and 100 workers to produce a single 351-foot wind blade for LM Windpower’s factory in Spain. Although these are some of the longest blades manufactured today, the process is similar regardless of the blade’s length.

To improve and streamline the manufacturing process, a multidisciplinary team, led by GE Research, is currently investigating the feasibility of embedding sensors into GFRP wind blades during production. The sensors would measure temperature, resin flow and curing as the blade is being manufactured, with the goal of reducing cycle time, material usage and overall costs. The research is being funded by NextFlex, one of eight Manufacturing Innovation Institutes established by the U.S. Department of Defense as a public-private partnership. (IACMI – The Composites Institute is another.)

Through its consortium of 100 companies, academic institutions, non-profit organizations and government agencies, NextFlex works to foster the growth of flexible hybrid electronics (FHEs) in U.S. manufacturing. FHEs are formed by placing integrated circuits (ICs) and other electronic components onto flexible, stretchable and conformable substrates, such as film. This reduces the weight and size of these electronic circuits and opens up the possibility of incorporating them into products in many new forms. FHEs are currently being tested for medical wearables, asset and structural health monitoring systems, flexible array antennas and soft robotics.

“The advantage that you get with FHEs is that you can build electronics in form factors that you typically can’t [build] with conventional electronics,” says Scott Miller, director of technology at NextFlex. “You also have the potential to do some really important size, weight and power trade-offs that you couldn’t get without the lightweighting of the electronic systems.”

Building the Sensor

NextFlex consortium members selected the GE Research sensor project because of their widespread interest in using FHEs for asset monitoring. Nancy Stoffel, principle engineer of GE Research’s electronics and sensing group, is the team leader, and Shridhar Nath, GE’s platform leader for onshore wind, is the expert in wind blade technology. Binghamton University in New York is contributing knowledge and experience in electronics manufacturing, reliability and material systems, while Georgia Tech brings expertise in additive manufacturing of flexible radio frequency (RF) modules and passive wireless sensors. The project team will also create embedded sensors for carbon fiber composites, and helicopter manufacturer Sikorsky is participating to guide the specifications and needs for monitoring the structural health of aircraft components operating in the field.