Keith Johnson at the WSJ's Environmental Capital blog has a look at proposals to reduce the price (and time taken to construct) of offshore wind farms by using concrete instead of steel in the supporting structures.
Sometimes the race toward clean energy is tripped up by politics. Other times, by nuts and bolts. Or steel.
Offshore wind power is supposed to be the great white hope of renewable energy. Out of sight, offshore wind farms could theoretically supply as much electricity as the U.S. currently produces with coal, gas, and nuclear plants. Britain fancies itself the “Saudi Arabia” of wind power, given its abundant offshore wind resources. So far, though, that’s translated into just under one-half of a regular coal-fired plant. (And things aren’t getting any better this week.)
What’s the holdup? Lots of things. Offshore wind costs more than regular, onshore wind—which already costs more than traditional power sources. Getting transmission lines from offshore platforms to the electricity grid has scuppered loads of offshore wind projects. There’s another holdup—building offshore wind platforms means bidding for the same construction materials that are needed for a lot of other things, raising costs and delaying projects.
But what if offshore wind developers were to end-run the obstacles? Britain’s New Civil Engineer reports this month that wind-power development companies, including Germany’s E.On and Denmark’s Dong Energy, might have a solution: concrete instead of steel. At a swoop, that would eliminate the need for pricey steel and all the supporting cast needed to plant it in the seabed. Says New Civil Engineer:The project has the dual purpose of reducing industry reliance on steel monopiles for foundations and eliminating the need for the heavy lift ships and jack-up barges typically used during turbine foundation installation. In addition the large hydraulic hammers usually needed for piling are no longer required, further reducing equipment and support vessel hire costs.
Granted, developers have been trying to get around regular offshore bottlenecks for years. Floating offshore wind platforms, borrowing from oil-rig technology, are the current flavor of the day.