CorPower Ocean has successfully verified its C4 Survival Mode after weathering two major storms along the Portuguese coast last week.
It marked the most energetic period at the Aguçadoura site in northern Portugal since CorPower Ocean deployed its first commercial scale device in August.
With major depressions building up over the Atlantic, Storm Babet and Aline unleashed waves up to 13 meters, providing an ideal opportunity to test the C4’s design principle for robust operation in extreme weather.
The storms were widely reported, leaving a trail of destruction across Portugal resulting in strong winds, torrential rain, flooding and building collapses.
CorPower Ocean CEO Patrik Möller said: “This was our most robust test so far in terms of storm survivability. We are happy to report that the device operated as intended with minimum motion and loads, despite being battered by waves up to 13 meters. The C4 was fully submersed under wave peaks on a regular basis. Last week’s operation has provided solid verification of the C4’s ability to endure extreme ocean conditions.”
The C4’s unique Survival Mode feature is enabled by a frequency detuning principle. In big storm waves, the C4 exhibits almost no response to the incoming wave power. This limits the loading on the structure to a similar level to regular operation in moderate ocean conditions. The survival mode is the natural state of the machine, making it a passive fault tolerant protection feature.
With the device operating as intended in Survival Mode, the loads recorded were slightly lower than predicted by advanced simulation models. The models have been calibrated in several steps since 2012, by prototype testing in wave tanks and by the previous CorPower C3 scale 1:2 device that was operated at EMEC in the Orkney islands, Scotland in 2018.
Möller added “The unique storm survivability mode as demonstrated by the C4 is one of the most important innovations that CorPower Ocean has brought to wave energy. By designing devices that tune themselves to the ocean conditions, the combination of robust storm protection can be combined with strongly amplified motion and power generation in regular ocean conditions. We believe this feature, which can be compared to wind turbines pitching the blades to avoid overloading in storms, is key to make wave energy a reliable and competitive energy source .”
Photo Credit: Ray Bilcliff
