Energy Islands: Orkney’s radical marine power experiment

Posted: November 29, 2021 by oldbrew in Energy, innovation, Tides, Uncertainty, waves
Tags: ,

Mocean Energy’s Blue X wave energy converter at Forth Ports’ Rosyth Docks [image credit: Mocean Energy]


The article title says the experiment ‘is a blueprint for the future’, but tidal power devices have a long record of not exactly becoming a roaring success. When might this future arrive? Talk of being a ‘global leader’ sounds upbeat and optimistic, press-release style, but will there be enough – or any – followers? After the intro, we come to the prototype wave converter.
– – –
We’re standing, it seems, on the deck of a stocky, barge-like boat with yellow trim, going full steam, says the Institution of Mechanical Engineers.

Water whips past, flicking up foam. But the ‘boat’ is stationary – tethered to the sea floor, it is in fact a 1.5MW tidal energy generator.

Developed by Spanish firm Magallanes Renovables, the ATIR platform has two turbines submerged in the fast-flowing waters of the Fall of Warness, south of the island of Eday in the Orkneys.

The device is a piece of cutting-edge renewable-energy technology in a seemingly remote environment, but it is far from the only one here. Just 100m away there is another bright yellow tidal energy generator, the O2 by Orbital Marine Power.

Elsewhere, there are wave-energy converters and wind turbines. Onshore there are more wind turbines, electrolysers for the production of ‘green’ hydrogen, and infrastructure to put the gas to good use.
. . .
[Moving on, to a specific wave-energy converter …]

The Blue X device by Mocean Energy

Built entirely in Scotland, the 38-tonne machine has two main parts, connected by a giant hinge.

The front arm faces into the waves with a shovel-like part plunged 4m beneath the surface, forcing as much of the water’s energy as possible through the device. It houses a small deck, with a comms mast and access hatch, and one of two solar-panel installations.

The rear arm is much smaller, with another scoop-like extension beneath the water.

As waves travel along the length of the machine, its buoyancy forces it to flex around the hinge – once at the peak and once at the trough, rotating ±20º but accommodating more movement.

This reciprocal motion goes through a gearbox, where it is spun up to a higher speed and fed into the AC electrical generator.

The Blue X, forerunner of a planned utility-scale machine known as Blue Horizon, was created using generative design to find its optimal shape.
. . .
[Later, the solar panels are mentioned, but there’s a problem…]

The firm is also keen to integrate solar panels onto devices, and Blue X has two sets of panels when we visit.
Unfortunately, they are covered by seabirds – and, underneath the birds, a slight problem.

“We talk about bird poop a lot more now than I had expected,” says McNatt. “It’s a real challenge.”

Full article here.

Comments
  1. Graeme No.3 says:

    I’ve seen the tide flow between Mainland and Roussay which comes out in “the fast-flowing waters of the Fall of Warness, south of the island of Eday in the Orkneys.”
    My only comment is the japanese one ‘Rots of Ruck’, but I wouldn’t invest anything in this project.
    I assume that there are subsidies in these projects.

  2. stpaulchuck says:

    I thought we saw this or one like it some time back. Wasn’t very good.

  3. ilma630 says:

    Let’s just collect & compost the bird poop, and use the gas it produces. But then again, the company seems to be producing more gas in its blurb.

  4. Curious George says:

    Is there a good reason why not start with a smaller prototype?

  5. Dave Ward says:

    “This reciprocal motion goes through a gearbox, where it is spun up to a higher speed and fed into the AC electrical generator”

    Unless the gearbox incorporates some clever freewheels and one set of reversing gears the generator will be constantly speeding up in one direction, slowing down, then speeding up in the other direction. Quite apart from the mechanical stresses this will impose, the power generated will have a variable frequency AC component, and the level of that output will also be rising and falling with something approximating to a low frequency sine-wave. This inevitably means that to synchronise with the grid AC-DC conversion and battery/capacitor storage followed by DC-AC conversion will be needed.

    NONE of this equipment will have a long, reliable service life in a salty marine environment…

  6. Chaswarnertoo says:

    How much? Service life? Power supplied? Doubt any of that makes sense.

  7. oldbrew says:

    At 38 tonnes it may seem big but the article says:

    The Blue X, forerunner of a planned utility-scale machine known as Blue Horizon, was created using generative design to find its optimal shape.
    . . .
    Retzler and Mocean co-founder Cameron McNatt believe the future could also hold large utility-scale deployment, with dozens of megawatt-scale devices joined together.

    – – –
    Re. subsidies:

    When it comes to government support, however, tidal seems to be more in favour. “Just as tidal energy has, wave will need revenue support, the equivalent of Contract for Difference-type funding, and we need support for early projects to get them to commercial scale,” says Retzler.

    They argue that wave energy has far more potential sites than tidal.

  8. ilma630 says:

    I think its ‘optimal shape’ will be in pieces in the scrapyard, where all these schemes end up.

  9. Gamecock says:

    What’s the point of generating electricity south of Eday in the Orkneys?

  10. oldbrew says:

    Gamecock — it’s where EMEC do their tests, including hydrogen production from wave power.

    https://www.emec.org.uk/about-us/

    Update: they have six test locations…

  11. Gamecock says:

    “Grid connected tidal test site.”

    Grid ?!?! In Eday ?!?!

  12. oldbrew says:

    Tidal energy innovators take share of £116M UK government investment
    December 7, 2021

    The new funding will support British businesses developing new green technologies to reduce carbon emissions and utility bills and remove greenhouse gases from the atmosphere.

    https://www.offshore-energy.biz/tidal-energy-innovators-take-share-of-116m-uk-government-investment/
    – – –
    Investment?
    Reduce utility bills?

    Press release gibberish.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s