The renewable energy industry is characterised by a level of dynamism when it comes to technological innovation – new techniques are being pioneered that increase efficiency while mitigating environmental impact.
Even if the oil industry is all vengeance and furious anger at the moment with gnashing of teeth and snarled denials, we’ve always got the renewable sector to make us feel all warm and fuzzy again.
This week it’s great to report on the successful results from the latest project involving the offshore wind industry which is constantly engaged in testing to make the sector more environmentally friendly. A group of developers and operators have identified a way to construct platforms that delivers far better outcomes – by vibratory piling instead of conventional impact hammering.
The project undertaken by RWE Innogy, Bilfinger Offshore, DONG Energy, EnBW, E.ON and Vattenfall involved two identical test sites with six steel piles. Three were vibrated and three were hammered into sandy, saturated soil near Cuxhaven which is very similar to soil in the North Sea.
The pile installation process proved to be ten times faster than hammering and generated lower peak noise emissions.
Jan Matthiesen, Director of Innovation at the Carbon Trust said, “Finding innovative methods to reduce the cost of installation will help to bring down the cost of offshore wind, making it competitive with conventional energy sources. The project results not only demonstrate that vibro techniques could be a viable method for piling, but also evidence of what can be achieved through industry collaboration.”
The pipes were kept in place for four months and were then subjected to a series of static load tests to check what would happen when the piles were subjected to typical lateral loads which are experienced in offshore conditions. The team found that the vibratory method has a major impact on the lateral load-bearing capacity. They theorise now that if various parameters such as vibratory frequencies or pile design are controlled it could be possible to achieve similar results with hammered piles.
This project is one of many research activities conducted by RWE Innogy. The company invests roughly €4.5 million a year in research projects that could reduce the costs of building and operating offshore and onshore wind farms as well as hydro power plants.
RWE Innogy’s Ben Matlock says the success of the project is spurring them to do more tests. He said, “Throughout the project we have collected a lot of important data that can now be used to further develop the technology to bring it offshore.”