Polamis tidal power in Portugal 1

[0707]

The first commercial wave farm has been exported to Portugal by Edinburgh-based Ocean Power Delivery, their Pelamis wave machine is at the cutting edge of marine.

“Each joint of the Polamis or “sea snack”contains a hidraulic pump. As wave move the section high pressure oil is pumped from the joints through motors, wich drive the generators that produce electricity.”

Go to the site bellow to see an animation of the system.

http://www.oceanpd.com/Pelamis/default.html

luis marques

 

[jmw]

Just think of all those pontoons and buoys that are scattered around the planet to act as moorings for all kinds of water craft and all exposed to the action of the waves and tides. Even if not ideally located for the maximum benefit one supposes they could scavenge at least some of the energy needs of the local community.
The question is as ever, what does is the energy cost/benefit ratio? and the financial cost/benefit? OK so wind power probably will never have the same capability as water power for energy production but we are seeing claims that wind turbines will just about pay for themselves within their claimed life expectancy (never mind the subsidies).
We also have to ask how many sites are there that are optimum for this sort of scheme and what the environmental impacts will be. One assumes there was a study before this was installed.

As you may deduce, amid all the debate and the subsidies, the lies distortions, claims and counter claims I begin to be sceptical of just about anything these days and I keep reminding myself of:
[ul][li] ther's no such thing as a free lunch[/li]
[li]if it seems too good to be true it probably is too good to be true[/li]
[li]the degree of veracity can be determined by the inverse relationship between the truth and the slickness of the website and one factor is all important animation[/ul]

Oh well, I think I'm open to be persuaded that this is the best thing since sliced bread but maybe I am now a confirmed cynic.

On the other hand, the animation here wasn't that slick and didn't in fact reveal anything at all. I would have thought we could all envisage from the photos what would happen to the sausage string when the waves hit it so what i was expecting when i clicked on the animation was to see the action of the hydraulic generators illustrated. I suppose this lack of "sickness" should actually persuade me this is going to be the best thing since sliced bread.

OK, time for some party animals to chime in with some "positive waves" (Sorry, couldn't resist).

JMW

http://www.ViscoAnalyser.com

 

[SomptingGuy]

I reckon global warming is caused by all those wind farms reducing the natural wind levels and all the other eco stuff messing with the environment. What will be the effect of eliminating waves I wonder?

 

[0707]

sorry in my first posting you must read Pelamis instead of Polamis

luis marques

 

[oldfieldguy]

I cannot help but wonder how long it will be before we find out that extracting energy from the waves has enough of a damping factor to adversely affect the coastal eco-system.

You KNOW it's going to happen.

But it's cool technology until then...



old field guy

 

[PSE]

Hmm,

I thought that they would also capture the vertical motion of the wave as well by using the vertical forces induced on the anchor points. I would assume that could/would be problematic due to tidal influences. Dampening effects could be beneficial in some cases. Envision these around offshore oil platforms etc, providing power as well as potential reduction in effects from adverse sea conditions.

Regards,

 

[KENAT]

I've been aware of this for several years now, I thought it looked pretty good. They tested a subscale one a while back and last I looked at the website had a full size one off the coast of one of the Scottish Islands.

PSE, they capture the vertical motion by the fact the sections move relative to one another, at least that's my understanding. As regards damping, I believe they control this so it doesn't tear itself apart in strong waves.

As regards Somptings & old field guys posts, while a genuine concern I suspect on a global scale wave farms will be no worse than tidal Mangrove Swamps etc were before a lot were destroyed. Just like I still doubt that wind turbines 'absorb' more wind than the trees that once covered much of the earth.

KENAT, probably the least qualified checker you'll ever meet...

 

[ivymike]

waves are just another way to capture wind power, aren't they?

 

[PSE]

Kenat,

My reference was using the tether points as additional ways to generate power, supplementing the movement and power generation between sections.

Regards,

 

[KENAT]

I assumed you meant that PSE. As well as capturing the energy from the sections motion relative to each other you'd also use the motion relative to the sea bed.

I think you'd basically find you were trying to capture the same energy twice. I could certainly be wrong though.

KENAT, probably the least qualified checker you'll ever meet...

 

[KENAT]

ivymike, which is just recycled solar power!

Then again except geothermal & nuclear (maybe tidal thinking about it) pretty much all common energy sources are basically recycled sunshine.

KENAT, probably the least qualified checker you'll ever meet...

 

[SomptingGuy]

What about tidal power?

 

[0707]

Pelamis in a certain way is a form of tidal power

luis marques

 

[KENAT]

Um, Sompting I added that as an after thought in brackets "(maybe tidal thinking about it)" as tides depend on the mass of the sun & moon.

0707, I really don't think Pelamis is a tidal power generator. The different segments would rise fairly uniformally with the tide.

The wave power station you show would generate some power from tides though very little in comparison with waves and only twice a day (or 4 times if bi-directional). In fact unless there's a very fast tide I doubt the rate the air is forced out by tides would even turn the turbine.

KENAT, probably the least qualified checker you'll ever meet...

 

[0707]

ok you are right Kenat, but I just said in a certain way...

a start for your contribution to the discution.

luis

 

[KENAT]

In your defense it says tidal power at point 2 of the explanation, I just think it's wrong.

KENAT, probably the least qualified checker you'll ever meet...

 

[DrillerNic]

There is a (very controsversial) proposal to harness tidal power over the Severn Bore in the UK. The problem is, that building a barrage to capture the tidal energy will also stop the tide reaching teh coast and so destroy a globally vital eco-system for wading birds.... (not to metional stopping people being able to surf up the river Severn!)

 

[dcasto]

Wave energy comes from wind which is solar.

Tidal power comes from the rotation of the earth. If we put in enough tidal dams, we will stop the earths rotation.....

I just started a new chicken little story....

 

[KENAT]

Driller,

That scheme has been around in various forms as long as I can remember.

We even had an energy question based on it when I took my A levels over 10 years ago.

While I'd never say never, I have my doubts it will ever happen as a complete barrage.

Now a bunch of tidal turbines of some sort I can envision but a complete barrier, I'm sceptical.

dcasto, isn't it a combination of the sun & moons gravity pulling the sea toward them, the rotation of the earth causes the high point to move. So not only will the world stop spinning but we'll collide with the moon & sun;-).

KENAT, probably the least qualified checker you'll ever meet...

 

[dcasto]

That's what I learned in my astrophysics class, the rotation of the earth. I ought to repost and see if any physists can agree.