North America’s first floating grid-connected wind turbine was lowered into the Penobscot River in Maine on 31 May 2013 by the University of Maine Advanced Structures and Composites Center and its partners. The VolturnUS 1:8 was towed down the Penobscot River where it was deployed for 18 months in Castine, ME, along with a UMaine-developed floating LiDAR. The prototype employs a 20 kW Renewegy VP-20 wind turbine with a 9.6m rotor. It is 65-foot-tall that is 1:8th the scale of a 6-megawatt, 450-foot rotor diameter design. VolturnUS 1:8 was the first grid-connected offshore wind turbine deployed in the Americas. The VolturnUS design utilizes a concrete semi-submersible floating hull and a composite materials tower designed to reduce both capital and Operation & Maintenance costs, and to allow local manufacturing throughout the US and the World. The VolturnUS technology is the culmination of collaborative research and development conducted by the University of Maine-led DeepCwind Consortium. During its deployment, it experienced numerous storm events representative of design environmental conditions prescribed by the American Bureau of Shipping Guide for Building and Classing Floating Offshore Wind Turbines, 2013. It was taken out of the water in November 2014. VolturnUS floating concrete hull technology can support wind turbines in water depths of 45 meters or more, and has the potential to significantly reduce the cost of offshore wind. With 12 independent cost estimates from around the U.S. and the world, it has been found to significantly reduce costs compared to existing floating systems. The design has also received a complete third-party engineering review.
Scaling up
In June 2016, the UMaine-led New England Aqua Ventus I project won top tier status from the US Department of EnergyAdvanced Technology Demonstration Program for Offshore Wind. This means that the New England Aqua Ventus project is now automatically eligible for an additional $39.9 Million in construction funding from the DOE, as long as the project continues to meet its milestones. The developer asserts that the New England Aqua Ventus I project will likely become the first commercial scale floating wind project in the Americas. U.S. Senators Susan Collins and Angus King announced in June 2016 that Maine’s New England Aqua Ventus I floating offshore wind demonstration project was selected by the U.S. Department of Energy to participate in the Offshore Wind Advanced Technology Demonstration program. The project is opposed by Senator Dow with Bill LR1613. New England Aqua Ventus I is one of two leading projects that are each eligible for up to $39.9 million in additional funding over three years for the construction phase of the demonstration program. In 2020, UMaine expects costs to be $74/MWh by 2027 and $57/MWh by 2032.