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Power Earth Science Technology

The World's First Osmotic Power Plant 262

ElectricSteve writes "Her Royal Highness Crown Princess Mette-Marit of Norway officially opened the world's first osmotic power plant prototype on November 24. The prototype has a limited production capacity and will be used primarily for testing and data validation, leading to the construction of a commercial power plant in a few years time. Statkraft claims that the technology has the global potential to generate clean, renewable energy equivalent to China's total electricity consumption in 2002 or half of the EU's total power production" What's osmotic power? Wikipedia to the rescue!
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The World's First Osmotic Power Plant

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  • Impact (Score:4, Interesting)

    by Bellegante ( 1519683 ) on Thursday November 26, 2009 @11:23PM (#30242160)
    I wonder what environmental impacts this has, and if they will prevent these things from going into real use?
    • Re:Impact (Score:5, Insightful)

      by dakohli ( 1442929 ) on Thursday November 26, 2009 @11:37PM (#30242232)
      According to the wikipedia article, the main drawback deals with discharging Brackish water back into the ecosystem. If large amounts are produced, which seems to be the case it could change local salinity levels causing a change in the local aquatic life. I guess the question here is: Is it worth it? And is this change significant enough to really worry about it. Everything we do on the Planet changes it. I can't believe all change is bad. The earth's ecosystem is in constant flux anyway. I guess it is a question for the slashdot philosophers.
      • Re:Impact (Score:5, Insightful)

        by Rakshasa Taisab ( 244699 ) on Friday November 27, 2009 @12:41AM (#30242646) Homepage
        It might come as news to some, but nature is continuously discharging fresh water into salt water, producing brackish water on a humongous scale.

        It's called rivers flowing out into the sea.
        • Well, that's great and all, but there is such a thing as local ecology, which would be important to the locals. "Environmental concerns" are not some global, zero-sum game.
          • Re: (Score:2, Insightful)

            by DigiShaman ( 671371 )

            ...which would be important to the locals

            Could be important. Could. Change happens all the time in nature, but not all of it is bad. Until a full environmental study has been concluded, lets not take an alarmist view here without knowing the facts beforehand.

          • Re:Impact (Score:5, Informative)

            by icebike ( 68054 ) on Friday November 27, 2009 @03:32AM (#30243366)

            You do realize this is located at the mouths of rivers, where fresh water was and will continue to mix with salt?

            You had to read ALL THE WAY down to the 4th Paragraph to find:

            such power plants could be located wherever sea water and fresh water meet, such as the mouth of a river. They run without producing noise pollution or polluting emissions

            So any mixing of fresh and salt has been going on in these very same locations for millions of years and is perfectly normal.

            Somehow I think the Local Ecology will survive.

            • Since some energy can be extracted from mixing salt water and fresh water, it would be possible that this energy (in terms of water temperature) would be missed by fish.

      • by bytesex ( 112972 )

        If you do that nearish to a river estuary (which is a logical place to build these anyway), then that's something that would have occurred naturally.

      • Brackish water is released into the Eco-system all the time. Don't you have rivers running into the sea in your area?

        the natural place for such a power plant would be in areas where this process already takes place, and then tap the power of it.

        Your assessment is a lot like saying "Won't solar plants cause a lot of sunshine?"

    • Re: (Score:3, Insightful)

      by couchslug ( 175151 )

      Given the swill US rivers dump into oceans, perhaps combining this process with pollutant separation would improve the outflow while generating power.

      • Marking the above a troll is jingoism at best. Here in the USA we have achieved truly amazing levels of water pollution through stupid practices. There are numerous alternatives; the easiest to implement replaces sewage treatment plants with ponds which produce algae and methane gas, not to mention clean water.

    • It appears that it requires fresh water, and outputs salty water.

      Fresh water is in short supply in many parts of the world, and one of the ways people deal with this is to use electricity to desalinate salty water. For that reason, I don't think this is going to be very popular.

      • Re: (Score:3, Insightful)

        It appears that you may not have actually read the article.

        It's to be built where rivers run into the sea. Rivers usually run with fresh water. It takes input from the river, puts it in an osmosis chamber with water from the sea, and spits the result out into the area where that river water was going to mix with the sea water anyway. There's zero net loss of fresh potable water as compared to what was going to happen anyway (as part of the natural water cycle), and as they're dumping the result into an area

  • by JuzzFunky ( 796384 ) on Thursday November 26, 2009 @11:29PM (#30242192)
    I wonder if you could use the energy to power a desalination plant and then use the fresh water to power the.. hang on... I've gone cross eyed...
    • by Anonymous Coward on Thursday November 26, 2009 @11:44PM (#30242286)

      I would advise against that kind of project. You'd get arrested for breaking the laws of thermodynamics.

    • Actually, that could work, not in the perpetual energy sense obviously, but certainly you could take the concentrated salt product from your desalinization process and recoup some of the energy by using it for osmotic fuel in this process.
  • by goodmanj ( 234846 ) on Friday November 27, 2009 @12:53AM (#30242708)

    I was skeptical of the numbers, so I looked around to figure out how much energy we're talking about here. This link [] discussing desalinization is pretty useful... what we're talking about here is a desalinization plant run in reverse.

    The short answer: 0.66 kcal (2760 joules) per liter of salt water converted to fresh water, so you'd get the same order of magnitude of energy *back* with an osmosis plant. The Mississippi river flow rate is 17 million liters per second at New Orleans, so the maximum possible energy output is 47 GW!

    I don't see any obvious efficiency-loss factors here: it should be possible to do this pretty efficiently.

    Another way of looking at the problem: the osmotic pressure difference between fresh water and seawater is 28 bar, which is equivalent to 280 meters of hydraulic head. That's roughly the same pressure gradient as is found across the Hoover Dam.

    Now, the technical challenge of building miles and miles of carefully-folded osmotic membrane, and keeping it clean, is a bit daunting. But in theory, it should work!

    • Re: (Score:2, Funny)

      Oh, well, if the theory is sound, then I don't see the problem with a large government/private sector cross over project in the New Orleans area.
    • Re: (Score:3, Interesting)

      by FlyingGuy ( 989135 )

      Ever looked at the water coming down the Mississippi? I wonder what the silt content per liter of water is?

      Now I am not a RO expert, not by a long shot, but I know that the water coming to the membrane has to be fairly particulate free.

      I really cannot fathom what kind of pre-filtering would have to be done to make this work in such a river basin. Perhaps in am area where there is a huge glacier run off that is pretty clean to begin with. <shrug>

      • by goodmanj ( 234846 ) on Friday November 27, 2009 @02:57AM (#30243210)

        You ain't seen silt until you've seen a real glacial runoff river.

        But yeah, I have no doubt there are some serious and maybe impossible engineering challenges, I'm just making the point that from a basic physics perspective, the energy is there.

      • Filtering water is something man has been doing for hundreds of years. Id wager we have some good technology for that already. Even still if what you say is true the particulate will likely cause a drop in efficiency which will hurt profit margins but considering the efficiency of the system as is, is 0% any improvement will be significant.
    • Re: (Score:3, Insightful)

      by plague911 ( 1292006 )
      The good part is that you can do a good crapy job and it still will be a major positive Considering the efficiency right now of the system is 0% a quick dirty and CHEAP solution can do nothing but provide a massive amounts of virtually free energy. This is one of these things like geothermal/solar energy. The ability to do them right requires the right land/environmental structure. In a lot of areas this will not make sense. However in the right area the profit margins are nice and high. Im not sure if peop
  • by InvisibleClergy ( 1430277 ) on Friday November 27, 2009 @12:54AM (#30242714)

    Oh wait, Statkraft? Gosh, I thought they were talking about something important for a moment there.

  • by mwkohout ( 46192 ) on Friday November 27, 2009 @02:34AM (#30243098) Homepage

    This is all being built next to Oslo's Fjords....

    No wonder Slartibartfast won an award for them!

  • I think an osmotic power plant is the lamest type of power i can think of.

    Fusion is the only way i can see it going, really if we are going to be great conquerers of the galaxy, and fly around in Millennium Falcon type spaceships.

    Anyway, Fusion is the only way to go because, we will either fix the problem, or maybe blow ourselves up.

    It will be a race between ITER and the LHC.
    Between explosion and implosion.

    Maybe we should hook.. them,. together?..

    ^mtrl drtw

  • by Anonymous Coward on Friday November 27, 2009 @06:34AM (#30244194)

    It's merely the first with a proper marketing scheme... :p

    Since 2005 a 50kW test installation has been working in Harlingen, the Netherlands. This is a POS (pressure retarded osmosis) installation just like the Norwegian one. A 10kW RED installation has been installed not 20km away in the Afsluitdijk barrier dam.

I've noticed several design suggestions in your code.