October 5 - Mammoet has installed a tidal power plant (TPP) in the Netherlands on behalf of Tocardo Tidal Turbines.
The turbines were installed at the Eastern Scheldt storm surge barrier (Oosterscheldekering). The project, known as OTP2, comprised five tidal turbines in a steel structure with a total weight of 500 tonnes.
The installation of the turbines posed a challenge to Mammoet, as it was not possible to drill into the columns of an active flood barrier. Mammoet worked with Huisman Engineering to secure the structure using a pull-rod clamped on to each column; a coupling jaw was placed on each column to guide the TPP into place.
The TPP steel structure was built by Huisman at its fabrication yard in Schiedam; Mammoet transported the 50 m x 21 m unit using 24 axle lines of SPMTs on two coupled barges to Neeltje Jans for installation.
Mammoet explained that there was only a one-and-a-half hour window to complete the installation. It was not possible to use conventional anchors due to concerns about damage to the seabed. The double barge also needed to be moored at a safe distance of 30 m from the surge barrier due to strong currents.
Mammoet designed a special mooring system using the remaining anchor points from the original installation of the storm surge barrier. Extra buoys were put in place to ensure the anchor lines would not touch the seabed.
During installation Mammoet manoeuvred the double barge from its anchor points toward the barrier using winches, secured its position, and then hung the TPP on the pull-rods.
Work is now under way to complete the final installation of the TPP, so it can enter full service and begin generating tidal energy.