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New Tidal-Energy Testbed Launched In Devon

Posted by timothy on from the lowered-might-be-a-better-word dept.

JaJ_D writes " According to the Beeb, Lynmonth in North Devon (in the south west of the UK) have just launched a new tidal energy generating system. The system is different to others by having the rotor blades fully under water and turning at about 20 rpm (so no harm to the fish). Each '...single 11 metre-long rotor blade will be capable of producing 300 kilowatts of electricity and will be a test-bed for further tidal turbines' Clean, relatively cheap and very little damage to the environment either by discharges or damage to the views. I wonder how many more will be made."

6 of 62 comments (clear)

  1. No harm to fish?!? by isorox · · Score: 3, Informative

    rotor blades fully under water and turning at about 20 rpm (so no harm to the fish).

    Erm, 11m blades, spinning arround, mean the outside of the blades travel 3.14*2*11*20/60 metres per second, thats about 50mph. I wouldnt want to be hit by one of them!

    1. Re:No harm to fish?!? by Anonymous Coward · · Score: 1, Informative

      I think you might have gained an extra 2 - you want omega.r, not omega.d. Not that different in the end though - it's still ~25 mph, which I certainly wouldn't enjoy swimming through if I were a fish.

    2. Re:No harm to fish?!? by mark2003 · · Score: 2, Informative

      It's not the speed of the balde that is important - rather the interval and the width of the blade. 20 RPM with two blades means a blade passes through any point every 1.5 seconds - it all depends if the fish can swim more than the width of the blade's cross-section in 1.5 seconds.

      Er... sounds like a fish blender to me!

  2. Re:I'm impressed by lirkbald · · Score: 4, Informative

    They have. California, at least. If you take the 10 east from Los Angeles, you'll see literally thousands of windmills through some of the mountain passes. I think my electric bills usually indicate that one or two percent of my power is coming from wind power.

    The problem with both wind and tidal is you can't just toss them up anywhere- you need somewhere with steady, fairly strong winds, or unusually large tides. I don't know much about tidal, but I doubt florida is going to have much luck with wind power- it's dead flat, and the best places for wind power tend to be mountain passes, which 'funnel' in the wind.

  3. More information. by JaJ_D · · Score: 3, Informative

    The beeb have released a Real audio file here. May be of interest

    Jaj

  4. Centralization still has advantages by Anonymous Coward · · Score: 1, Informative
    (Spamalamadingdong, posting AC because I used mod points here... but I didn't mod the parent.)
    I think that US states like California and Florida need to investigate energy strategies like this as soon as possible. With all these recent improvements with Solar, Wind, and now Tidal energy sources, I'm amazed that the US isn't doing more to utilize them.
    As other posts have noted, the NIMBY is one problem. If you ask me, the real problem is the assumption that power needs to come from large, centralized facilities run by big companies. So we end up with huge, multi-million to billion dollar projects like building new nuke plants, giant wind farms, immense dams, etc. This results in more eyesores in the form of transmission lines.
    Au contraire, there are lots of good reasons for putting a fair amount of anything in one place. To list a few off the top of my head:
    1. If you have a resource like wind which is unevenly distributed, putting a lot of capacity in the best spots is more cost-effective than spreading it out for spreading's sake.
    2. Maintenance of any system is essential, and the maintenance costs will be lower if the travel requirements are smaller. Putting things closer together is better for that.
    3. If you have any sort of power-conditioning systems required to hook into the grid, one big one is usually cheaper (and less costly to maintain) than two little ones.
    You're right that things like transmission losses do make it rather silly to try to generate all our electricity from the wind blowing in South Dakota, but you can go too far the other way too; just look at the per-watt costs of a Bergey turbine on your own personal tower vs. one of the state-of-the-art multi-megawatt machines, and you have to admit that some things work better when they're big.