Predicting waves could double ocean energy capture

Surfers spend half their time on the water sitting upright on their boards, scanning the horizon for the next suitable wave.

The reason of course is that a wave’s size and power is going to tell you a lot about how good a ride you’re likely to have.

Well, the same is true of wave energy capture technology. Put simply, some waves are better than others. To tackle this problem and to get the most out of the waves coming their way, researchers have been working on technology to predict wave power.

We already mentioned this development here at EarthTechling. Now the same team, which is being led by the University of Exeter, in western England, has published research claiming new methods for predicting waves could double current energy capture.

The study was carried out by mathematicians and engineers from the University of Exeter and Tel Aviv University.

The research focused mainly on point absorbers, commonly-used floating devices with parts that move in response to waves, generating energy which they feed back to the grid.

The key to the making the point absorbers work better, the researchers said, was to try and ensure their response matched as closely as possible the force of the waves.

By predicting the force of the oncoming wave and ensuring the energy capture device responded accordingly, this would also limit the likelihood of the device being damaged and mean it would not need to be turned off in stormy conditions, as is currently the case.

Improving the efficiency of wave technology could have significant repercussions for future energy needs, particularly in the United Kingdom.

Marine energy is believed to have the potential to provide the UK with its electricity needs twice over. At present, however, technologies to extract and convert energy from the sea are far less advanced than other renewables, such as solar and wind, and remain as yet largely uncommercial without the intervention of government subsidy.

The University of Exeter is collaborating with Ocean Power Technologies (OPT), a wave energy device developer, to exploit and further develop the results from this research.

OPT wants to use the prediction models in its PowerBuoy wave energy systems. According to OPT, this technology would allow the PowerBuoy to fine-tune its electronic capabilities to better “prepare” for the shape and size of waves as they approach, significantly boosting the power output of the PowerBuoy, and reducing the cost of the energy it produces.

Co-author of the research Dr Markus Mueller of the Environment and Sustainability Institute at the University of Exeter’s Cornwall Campus said in a statement: “The next step is for us to see how effective this approach could be at a large scale, by testing it in farms of Wave Energy Converters.”

Development and deployment of the new technology is being funded by the WavePort project, an initiative of the European Union’s Seventh Framework Programme for research and innovation.

Paul Willis, EarthTechling