Land-based applications don’t have to be as big because the loads are less demanding. When you go to offshore applications, designers must meet an entirely different engineering requirement. “It turns out that in most of these larger blades using carbon [fiber] becomes a necessity,” Dagher says. “So, you’re looking at carbon materials and making sure you have high-quality materials and fiber systems.… Then you start looking at trade-offs: How much carbon? How much glass? Will I make it heavier if I put glass on, or do I make it lighter with more carbon?”
Once the tower is completed and connected to the grid in 2022, it will have over 100 sensors on board to monitor its performance over five years. “The results will be used to deploy optimized floating farms around the U.S. and the world,” Dagher says.
The Drive to Reduce Costs
Reducing market prices for carbon fiber may be key to achieve the cost savings that the industry seeks from these mega-turbines. The DOE grant behind Maine Aqua Ventus is part of a national competition to drive floating U.S. offshore wind costs below 10 cents per kWh. According to Dagher, independent estimates from the National Renewable Energy Lab project that the levelized cost of electricity will be below 8 cents per kWh for commercial farms, and perhaps as low as 6 cents per kWh when 15 MW turbines are used.
The Maine Aqua Ventus’ promise to achieve these savings is already driving investors to UMaine. The Advanced Structures and Composites Center is in discussions with major offshore wind developers and investors who are ready to buy into the technology once it is deployed at full scale and de-risked.
As Dagher says, “The U.S. offshore wind market is heating up and we now have a real industry taking off.”