We Can Now Turn Ocean Waves into Electricity and Fresh Water We Can Now Turn Ocean Waves into Electricity and Fresh Water

We Can Now Turn Ocean Waves into Electricity and Fresh Water

by Jordan Keenan May 24, 2016

An Australian company is on the brink of revolutionizing the green power movement with the latest version of its wave energy technology that harnesses electricity from the movement of the ocean.

This innovative system developed by Carnegie Wave Energy is named CETO, after a Greek sea goddess. The latest version – CETO 6 – incorporates submerged buoys anchored to the sea floor that move up and down with the ocean swell. This movement powers an on-bard hydraulic pump, turning kinetic energy into electrical energy, which is then transferred to a facility onshore via undersea cables.

In addition to electricity, the CETO system also supplies freshwater, as the energy generated can be used to both pump sea water on shore and operate a reverse osmosis desalination plant.

Design for the latest iteration of the CETO wave energy technology

The potential value of harnessing the waves, according to Carnegie Wave Energy’s CEO Dr. Michael Ottaviano, is that “wave energy has been estimated to be able to supply more than the whole world’s current power consumption.” While the idea of harvesting ocean energy isn’t new – the first patent for a device dates to 1799 – only recently have researchers made significant headway on creating resilient and efficient hardware.

An earlier iteration of this technology – CETO 5 – was first successfully implemented on an island off the coast of Perth in 2014. Three buoys, each producing 250 kW, successfully operated for 13,000 cumulative hours at a depth of 5.8 m in waves over 3 m. CETO 6 sees the buoys upgraded to providing 1 MW each, as well as being capable of operating at greater depths and higher sea states.

Animation of how CETO 5 works

Carnegie Wave Energy is now experimenting with the idea of “micro grids“, which combine CETO’s ocean-sourced electricity and freshwater with solar panels and battery storage, to enable coastal and island communities to autonomously generate all the energy and water they need on-site. The first micro grid will be at that same island off the coast of Perth.

In addition to CETO’s particularly high energy output and added capability of producing freshwater, the fact that the buoys are submerged makes CETO distinct from other wave energy initiatives. Not only does it make for a much more aesthetically pleasing option, it also means the buoys are less affected by storms.

Wave energy offers certain advantages over solar – namely that a wave farm is smaller than a solar farm for a comparable output, and waves are much more consistent and predictable around the world, whereas solar’s effectiveness is reduced by cloud cover and short winter days.

Another endearing benefit of the technology is that CETO buoys act as artificial reefs and promote marine biodiversity. As Dr. Ottaviano explains of the experimental CETO 5 rig near Perth, “we increased the amount of marine life from about seven species before the system was deployed to 27 species when it was operating.”

Marine life swimming around a CETO buoy

Carnegie Wave Energy may soon be coming to a shore near you. It has a plan for a 10 – 15 MW project in the UK, as well as major projects in the pipeline for Ireland, Canada, Bermuda, Chile, and micro grids in Mauritius and other remote areas and islands.

  • FujiToday

    Great concept.

  • Matt Robinson

    I suspect most marine biologists would be horrified by the suggestion we should seed our oceans with these crackpot schemes. At a time when we should be reducing our impact on the environment as much as possible, it’s completely counter-intuitive to suggest we should allow such an increase of our environmental footprint.

    Offshore wind and tidal generators are bad enough, but giving voice to every idiotic energy scheme in the name of ‘clean’ energy is off the scale of irresponsibility.

    • Karl Gross

      Matt I suggest you read the entire article and the attached links Carnegie Wave Energy did a two environmental impact assessment on their current designed units. I will admit they do look fairly noninvasive. Considering the destruction and death to the Great Barrier Reef in 2016 this year from climate change El Nino I’m all for new inventive forms power as long as it does not impact our environment.

      • Matt Robinson

        I’ve already read both the article and the supplied links.

        Both the AIT article and the associated links look to be nothing more than fluff pieces to ‘sell’ the technology. No hard data and no independent scientific reports from oceanographers or independent marine scientists.

        I don’t see a noninvasive technology at all. For this to make any kind of substantive impact on cleaning up our energy, the level of deployment has to be huge – tens of thousands of these in huge ‘farms’.

        Coral reef bleaching is tied firmly to water temperature, which is a secondary effect of accelerated global warming, which itself is a secondary effect of mass atmospheric pollution.

        It really doesn’t matter what ‘spin’ they put on this, there will be a significant environmental impact on our oceans, with little to no mitigation of emissions.

        • BendCris

          But then….don’t think they are advocating replacing our entire electric grid with these…MORE, these could be used as part of the shift away from fossil fuels. Definitely like to ask the long range impact. But I would take this in a heart beat over Nuclear, coal, hydro dams and archaic wind farms. Our transition away from polluting technologies will be a ‘ride’ …even down paths that lead to short lived tech solutions. I think here, their intentions are good…