June 25, 2024 — A green mineral scattered along the Atlantic Ocean’s seafloor is the latest hurdle for President Joe Biden’s plan to jump-start the offshore wind industry.
Glauconite is sediment that resembles the green sand in a fish tank. But if pounded by pile drivers, it shatters to form a claylike layer.
Monopiles — hollow steel tubes driven deep into the seafloor to support turbine towers — often cannot be hammered through the thick paste, cutting off the cheapest and most widely preferred foundation for the first U.S. offshore wind farms.
“It’s almost like magic what happens when the monopile is driven through it,” said George Hagerman, an offshore wind expert at the Department of Energy’s National Renewable Energy Laboratory. “It all of a sudden becomes very, very, sticky, almost like plaster.”
Identified in several offshore wind lease areas in the north Atlantic, the mineral poses a growing hazard to offshore wind projects that already face high costs and razor thin margins. At least four wind lease areas off the coast of New England and New York — Beacon Wind, Empire Wind, New England Wind and Sunrise Wind — have all have grappled with glauconite.