Path To Better Offshore Wind Turbines: ‘Embarrassingly Obvious’

Floating wind turbines, you might recall, are proposed as a way to access the superior wind available in deep ocean waters. But a Cambridge University engineer believes that closer to shore there might be stunningly simple new approaches to turbine construction that could improve the return on offshore wind power investment.

Jim Platts from the university’s Institute for Manufacturing, a veteran of the offshore wind industry, says the harvesting ratio of offshore turbines – that is, the amount of the energy produced vs. the energy used to make the turbine – could be vastly increased if manufacturers used guy wires to hold turbines in place while also building with composite materials instead of conventional steel.

offshore wind turbine, efficiency, guy wires, composite materials

image via Shutterstock

To hear Platts tell it, making this change is something of a no-brainer.

“The development of the wind turbine industry, and the way in which it works with the civil engineers who make the heavy supporting towers and foundations, which are not visible out at sea once the turbines are installed, mean that we have ignored something which is almost embarrassingly obvious in our race to meet the targets set for renewable energy production,” Platts said in a statement.

You might be surprised at how much material it takes to do the standard offshore wind turbine installation. The towers look nice and slender rising out of the sea, but like an iceberg, there’s a lot more going on under the surface. “What you don’t see are the far heavier supporting structures below the surface that they slot into,” said Platts. Those foundations use up to four times more steel and concrete then onshore turbines.

To close that gap, Platts recommends guy wires – aka, stay cables – anchored to the sea bed. (He doesn’t say if they would attach to the tower above or below the water’s surface.) According to Platts, early studies show that  guy wires would allow for slimmer towers and “substantially less weighty” foundations.

Pete Danko is a writer and editor based in Portland, Oregon. His work has appeared in Breaking Energy, National Geographic's Energy Blog, The New York Times, San Francisco Chronicle and elsewhere.

  • 1barbaradurkin

    The problem with wind energy is that it’s redundant because it requires backup conventional energy. We pay twice to further fund unscheduled maintenance, the Achille’s of on and offshore wind.

    Iberdrola, Central ME Power, represented a $1.4 Bn. New England ratepayer funded transmission upgrade from ME to MA would allow the integration of wind energy to the grid to FERC. The System Operator ISO New England curtailed 9 renewable energy projects, five are First Wind projects, because the system can’t handled wind. Subsea cabling, $6 million per mile, will handle wind when land-based upgrades, $1.4 billion, fail?

    Offshore wind turbines that feature monopile foundations, such as specified by Cape Wind, are, “discontinued”, “sinking”, “shifting”, and “corroding”, where deployed offshore UK. Perhaps the 6 international wind energy experts who graciously reviewed the Cape Wind EIS should not have been ignored when they recommended a smaller plan, preferably land-based, to Cape Wind utility scale wind project.

    • Pete

      All energy production systems require backup. See: San Onofre Nuclear Generating System. As for issues with monopile foundations, the DNV joint industry project report addresses that. I would be surprised if Cape Wind decides to be the one offshore wind power development in the world to ignore it.

  • jalbertini

    And what happens to these when sea levels rise 20-50 feet submerging much of what WAS above the waterline?

    • Pete

      Interesting thought. Maybe floating turbines are the answer. But actually, the Intergovernmental Panel on Climate Change estimate is for sea levels to rise three or four feet by 2100 — a major concern for low-lying coastal areas, but perhaps not so much for offshore wind turbines.
      Pete Danko

      • jalbertini

        True estimates of sea level rise IF ALL the glaciers in Greenland melt equal 24 FEET!

  • jalbertini

    Distributed SOLAR is the answer NOT wind!!!