A handful of wave power plants are in operation around the world, but it is still considered an emerging technology with high costs and the problem of damage from ocean waves. Digital technologies are helping to increase efficiency and improve preventative maintenance.
Finnish company AW-Energy Oy (AWE) is using various digital tools to enhance output from the 350kW SURGE2 system on the coast of Peniche, Portugal, using the company’s WaveRoller oscillating wave surge converter technology.
A new substation with a higher rating is located onshore at the site, built by a Spanish team from PROinSENER Energía and based on Abengoa design specifications.
One of the innovative features of the project is its use of digital hydraulics which allow it to run at a much higher pressure than the original SURGE project. Because the grid is separated from the wave side both can be optimised, says CEO Christopher Ridgewell. By applying a large counterforce to the panel it can take up to 2MW of power which is then smoothed out before being fed into the grid. Grid stability is an issue, but the system has accumulators which can deliver power when frequency drops.
“We are taking digital hydraulics to the next level and thus we’re able to optimise the energy recovery for the prevailing wave conditions using high pressures. The software component is a significant portion of this technology,” Ridgewell says.
The company has tested hydraulic systems at a full scale 2MW grid connected test facility in Järvenpää, Finland, which was exposed to sea conditions for an extended period. The technology has been tested in Ecuador and off the UK, and other projects around the world are imminent, Ridgewell says.
While it has lagged wind and solar, wave power will be needed to reach ambitious carbon emission reductions around the world. And it could provide a solution to the problem that wind and solar resources drop off around 7pm, just in time for the evening peak.
Recently AWE was issued a manufacturing certification from Lloyd’s Register, one of the first for a wave power technology. This will help with financing and insurance.
AWE secured EU Horizon 2020 funding for a 1MW MegaRoller project, which is still under development. The next-generation Power Take-Off solution for oscillating wave surge converters is based on multiple hardware and software innovations.
Another innovation being pioneered by the company is auditory neural science, using the way the mind understands speech to predict the way waves behave.
Research is being carried out in collaboration with the Leibniz Institute of Neurobiology and Dr Patrick May of Lancaster University. If new software can better predict the next wave, less reserves need to be kept in the accumulator and more power can be fed into the grid. “I’ve never seen such excellent wave by wave prediction,” said
This intelligent system could be a year away, however.