Floating wind ‘promising’ off Oregon, report finds

The study, Oregon Offshore Wind Site Feasibility and Cost Study, said floating wind would be required off Oregon because 97% of the 62 GW of available technical offshore wind energy resource in Oregon is in water depths greater than 60 m.

The study noted that although floating offshore wind energy is still in a ‘nascent’ stage of development, it is advancing toward commercialisation in both Europe and Asia. It highlighted recent European strike price data for bottom-fixed offshore windfarms, which show a decline of about 65% relative to 2017, for projects expected to be commissioned by 2025. The NREL also highlighted new US price data, including an analysis of the Vineyard Wind power purchase agreement, reduced finance costs for offshore wind, larger turbines and falling unit costs for floating platforms, in part due to scaling to larger platform sizes, and further system wide cost reductions.

The authors of the study estimate that levelised cost of energy (LCOE) could range from US$74/MWh to US$53/MWh in Oregon for floating wind technology in 2032. The results are based on assessments of five potential sites using a conceptual NREL-designed 15-MW wind turbine. These costs reflect lower LCOE than a similar study conducted into floating wind offshore California because of new cost and technology data that support lower capex and opex than was previously modelled.

The NREL compared full-scale 600-MW project costs for a site near Coos Bay, Oregon to a 24-MW pilot-scale Principle Power project proposed in 2014, also off Coos Bay. The pilot-scale project costs were three times higher than the commercial-scale project using the same financing and energy production. “This analysis demonstrated the benefits of building projects at commercial scale,” said the NREL.

“Overall, the prospects for offshore wind in Oregon look promising for large-scale electricity generation,” the authors of the report said. “Floating technology is maturing rapidly, and offshore wind can provide a carbon-free alternative electricity source in coastal regions, especially in the southern region where offshore annual average wind speeds are near 10 m/s and among the highest in the US.

“However, wind resource assessments are based on single ensemble setups and validations are sparse, so higher-resolution resource data is needed to reduce uncertainty for investors, lawmakers, developers, and utilities considering offshore wind in Oregon.”

The authors of the report said there will also be significant challenges for offshore wind to overcome in Oregon, including optimisation of floating technology, coexistence with the fishing industry, mitigating impacts to wildlife and the viewshed, and integrating with the existing land-based grid.

“However, offshore wind can play a long-term role in helping to meet state and regional electricity-generation goals and could be synergistic in relieving congestion at some grid locations,” the NREL said. “Future work should focus on assessing these potential impacts to allow for offshore wind development to progress in a manner that is appropriate and fair for all stakeholder communities.”

The study focused on assessing the present and future costs of floating offshore wind technology deployment in the state of Oregon at commercial scale. It was funded by the Bureau of Ocean Energy Management (BOEM), and built on a previous report published by NREL and BOEM in December 2016, Potential Offshore Wind Energy Areas in California: An Assessment of Locations, Technology, and Costs, which estimated LCOE for floating offshore wind in California at $100/MWh or less by 2030.