Portuguese 20MW wave power project

[AE-NMidlands]

Hell of a kicking they seem to take. Don't get me wrong, I hope they succeed but I don't know anything metal that does well in the sea without regular maintenance or replacement and that in itself is massively expensive to carry out with multi month system shutdown if it goes wrong at the wrong point in the year.

The dock sea surface interface point between air & water can be absolutely brutal.

If I ever backed something sea energy based, it would have to be subsurface, midwater and current depending not wave.

Absolutely agree, although not based on any professional involvement.

Haven't we also seen something proposed like a hollow vertical shaft with a turbine in the top of it pressurised by waves at the bottom? I think it was bi-directional, but now I'm wondering whether it would be better to have the fan run in just one direction and have the chimney pressurised by the waves, or have non-return valves so that the fan free-wheels as the waves suck back down... This seemed like a better way of using surface waves but with the moving parts put somewhere a bit safer!

[Moxi]

Yes we discussed this at some point and it was a build project on the planet mechanics program with Dick Strawbridge and Jem Stansfield.

I think one of the questions we came to was whether fine spray from the water column would damage the turbine blades and yes I believe we also said a system with separate turbines on the push and pull cycle would be better than a reversing turbine.

I suppose the other issue is that the volume of swept air is only relative to the wave amplitude so not making optimal use of the energy embedded in the water.

Still better off intercepting the energy at the earlier stage as wind with a conventional turbine.

Moxi

[Stig]

I'm sure I remember hearing about a trial using a turbine that had an aerofoil design that turned the same way whether the air in the shaft was going up or down. Likely a lot less efficient than a conventional turbine though.

I agree that if you're going to the trouble of building something in coastal waters then tidal is more valuable given we've already got good generation when it's windy.

[Joeboy]

I'd love to play about with designs and trial them. Don't seem to see tidal.venturi effect or swivel slipring type for power transfer. All seems very fixed installation big basic spinny thing. That environment is the killer though.for sophisticated. KISS I suppose.

I wonder if the much maligned VAWT style on a slip ring would stand a chance?

I bet you could have great fun with a 5 ft fish tank, pump, hose, meccano and a 3d printer?

[Joeboy]

Anyone?

https://www.facebook.com/marketplace/it ... 929260674/

[Bugtownboy]

Still, the question is why ?

I get the need for a predictable output, but the issues to achieve it appear difficult, particularly when compared to solar and wind.

Surely an overload of wind and solar plus some form of battery is achievable now with known output

Tie this to a continental network of interconnectors, why are we chasing the engineering unicorn ?