The University of Maine’s Volturnus offshore floating wind-turbine design has passed a two-year review by the American Bureau of Shipping, the university announced in a Sept. 14 statement. The bureau, a leading provider of classification and technical services to the offshore and marine industries, has completed the design review of the Front-End Engineering and Design documentation for the Voltunus, developed by the university’s Advanced Structures and Composites Center. The Volturnus is the first floating wind-turbine concrete semi­submersible hull to be reviewed and approved by the bureau—“a major milestone,” said Habib Dagher, principal investigator. The patented Volturnus is based on a concrete, four-column, semisubmersible hull concept. Construction of the floating concrete hulls for the 12-MW project is scheduled to begin in spring 2018, followed by installation of on-site anchors and cable laying the following spring; test-site installation of the floating hull and turbines will take place in fall 2019.