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Science Technology

Green Energy From Manhattan's East River 316

circletimessquare writes "New York City's waterways are geographically unique in that they force tides from Long Island Sound down the East River in one of the most concentrated, powerful flows on the East Coast. If all goes as planned, a company called Verdant Power will build a $20 million, 10 megawatt underwater turbine field there by late 2005. The turbines spin slowly enough so that they pose no threat to wildlife (har har), are placed in spots where they do not interfere with commercial shipping, and are deep enough to not interfere with recreational boating. About the only drawback to the scheme are the supply shortage periods when the tides are slack. The New York Times has the scoop."
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Green Energy From Manhattan's East River

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  • by Anonymous Coward on Saturday July 10, 2004 @05:17PM (#9663060)
    Maybe one day they'll be able to get clean water from it too.
  • by BCW2 ( 168187 ) on Saturday July 10, 2004 @05:19PM (#9663072) Journal
    I've seen a lot of green stuff in that river, but I didn't think it was energy.
    • I've seen a lot of green stuff in that river, but I didn't think it was energy.

      Thats because you came during the day, stop by at night, the green stuff will be glowing then.
  • by E_elven ( 600520 ) on Saturday July 10, 2004 @05:20PM (#9663079) Journal
    It's more of a brownish-octarine-indescribable colour. Wonder if smell could generate energy..
  • by Anonymous Coward on Saturday July 10, 2004 @05:21PM (#9663080)
    True green energy comes from Kryptonite.
  • Materials (Score:5, Funny)

    by napa1m ( 154836 ) on Saturday July 10, 2004 @05:21PM (#9663081) Homepage
    I wonder what they're planning on building these out of. I live a few hundred yards away from the east river in brooklyn and everything in the water for more than a day has the odd tendency to melt... or mutate.

  • fusion (Score:5, Funny)

    by clem ( 5683 ) on Saturday July 10, 2004 @05:22PM (#9663084) Homepage
    Yeah, isn't Doc Ock's ball'o'fusion at the bottom of the river now?
  • by spacerodent ( 790183 ) on Saturday July 10, 2004 @05:22PM (#9663085)
    Giant spinning fan blades don't really care how fast they're spinning when they hit soft squishy meat.
    • by i love pineapples ( 742841 ) on Saturday July 10, 2004 @05:33PM (#9663141) Homepage
      Is there even any wildlife capable of living in the East River??
      • no, viruses don't count as "life forms" according to biologists
      • by bman08 ( 239376 ) on Saturday July 10, 2004 @06:00PM (#9663252)
        Anything living in there SHOULD be killed before it rises up to feast on the flesh of men!
      • I used to live in the East River (well, on an island in the East River, not, like, in the river itself), and it's not an especially life-friendly place. A lot of the blame goes to Connecticut; their rivers drain out into the Sound. The Hudson's pretty bad where it runs past Manhattan, too, which is kind of sad, since upstream the Hudson's gotten so clean you can fish and swim in it (oh my god, environmental regulations worked, quick, libertarians, figure out a way to somehow shift the credit to the free m
        • Now I'm not saying that I particularly favor libertarian approaches to the environment, BUT, consider this--what if our system of lwas and govt were really set up to deal with environmental issues in a libertarian laws?

          How about the people in Manhattan (or wherever!) could get a big class action law suit going against the people who polluted upstream? What's wrong with that scenario?
    • Actually, depending on the speed of impact, the blades are more likely to push an animal away, rather than dice it up. Consider this example: someone brings a sword down very slowly on your outstretched arm. The arm will probably just move down with the sword. Try again but swinging the sword with Hearty Vigor. The arm probably comes off.
      • Actually, depending on the speed of impact, the blades are more likely to push an animal away, rather than dice it up. Consider this example: someone brings a sword down very slowly on your outstretched arm. The arm will probably just move down with the sword. Try again but swinging the sword with Hearty Vigor. The arm probably comes off.

        I just now tried this on my younger brother and sure enough, his arm didn't come off till I swung the sword real hard!

    • i would think the fish might even be entertained

      for us it would be like running through a rotating lawn sprinkler and avoiding getting wet ;-)
    • Yeah, I hear the windmills in Denmark chop up world-record numbers of birds.

      For the sarcasm impaired: that's the most ridiculous statement I've ever heard.
      • any multi-story building with large windows will kill birds. the total number of birds killed by windows vastly outnumbers the number of birds killed by windmills.
  • 10MW (Score:5, Interesting)

    by fcolari ( 699389 ) on Saturday July 10, 2004 @05:23PM (#9663097)
    10MW won't make a dent I think, but it's a good idea as an experiment. It would be barely 1% of the capacity of one of the nuclear plants up the road.
    • Re:10MW (Score:3, Insightful)

      by Nutria ( 679911 )
      10MW won't make a dent I think, but it's a good idea as an experiment.

      Sure, it'll make a dent. Small dent, yes, but so what?

      Even a Dubya fanboy like me knows that we need to diversify, instead of bleat and whine.
    • Re:10MW (Score:3, Insightful)

      But the nuclear plants are... NUCLEAR! OH NO!

      Tim
    • Re:10MW (Score:3, Insightful)

      by Anonymous Coward
      the article said that 10MW will save 650,000 barrels of oil per year. At $40 per barrel of oil that come out to be $26 millions.

      That's a lot of pizza
      • That's a ridiculous comparison--how many power plants right now run on oil?

        Cars, trucks, etc are the big users of oil for energy!
        • Re:10MW (Score:3, Informative)

          by DAldredge ( 2353 )
          In 2000 2.9% of generated power in the USA came from oil.

          http://fpc.state.gov/documents/organization/2342 3. pdf

    • It would be barely 1% of the capacity of one of the nuclear plants up the road.

      Actually, about 1% seems about right. A lot of nuclear reactors appear to be capable of just below or at 1GW.
    • Re:10MW (Score:5, Funny)

      by wideBlueSkies ( 618979 ) * on Saturday July 10, 2004 @08:07PM (#9663684) Journal
      What I'd like to know is how many Libraries Of Congress 10MW will light up.

      wbs.
    • 10MW won't make a dent I think, but it's a good idea as an experiment. It would be barely 1% of the capacity of one of the nuclear plants up the road.

      But $2/watt is a good price. Last time I looked solar panels were going for about $10/watt.

      Also: Around here solar panels generate the equivalent of about 5 hours worth of their rating per day and I bet a tidal generator would do significantly more than that.

      What's (24 / PI) * integral[0 = x pi] (sin(x)**3)? It should beat that because it would flat-to
    • Re:10MW (Score:5, Informative)

      by Jeremiah Blatz ( 173527 ) on Saturday July 10, 2004 @08:58PM (#9663841) Homepage
      10MW won't make a dent I think, but it's a good idea as an experiment. It would be barely 1% of the capacity of one of the nuclear plants up the road.
      The main problem with powering Manhattan is not the generation capacity, it's the transmission capacity. During peak load hours, the natural gas generator by my apartment kicks in. Supposedly, if the peak needs of Manhattan were generated off the island, then the wires to the island would melt.

      So, power generation in Manhattan doesn't need to be super cheap or super high capacity, it really just needs to be low-pollution and moderately inexpensive. They're not competing with nuclear or coal or large hydro, they're competing with on-demand natural gas, which is nowhere near as cheap.

  • Reminds me of (Score:5, Informative)

    by r.jimenezz ( 737542 ) <rjimenezh@NospAm.gmail.com> on Saturday July 10, 2004 @05:26PM (#9663105)
    There was an Ask Slashdot some months ago [slashdot.org] discussing ways to get off the grid using something like this. Whilst what the NYT article describes is certainly not for your average DIYer, some very interesting points were made in that Ask Slashdot about this form of enery generation.
  • 10MW (Score:2, Redundant)

    by nurb432 ( 527695 )
    Thats just a tiny contribution to the total usage....
  • Green Indeed (Score:4, Informative)

    by twitter ( 104583 ) on Saturday July 10, 2004 @05:28PM (#9663119) Homepage Journal
    At seven cents a kilowatt-hour, that's some green power. Dollar bill green, that is. Nuclear still puts out power at under three cents a kilowatt hour and it does so 24-7. You would think it's cheaper to run a water wheel.

    • Re: (Score:3, Insightful)

      Comment removed based on user account deletion
    • Re:Green Indeed (Score:5, Interesting)

      by tunabomber ( 259585 ) on Saturday July 10, 2004 @05:55PM (#9663226) Homepage
      Too bad that nuclear power looks a lot cheaper than it is due to the fact that it is heavily subsidized [taxpayer.net]. If we decide to subsidize a non-cost-effective energy generation, why not subsidize something that has fewer hazardous waste products, is more down-scaleable, and less of a magnet for terrorists- like wind or solar power?
      • Re:Green Indeed (Score:3, Insightful)

        by sp0rk173 ( 609022 )
        Not only is it heavily subsidised, the rates don't take into account the entire cost of mining and processing the radioactive material. "Cheap" nuclear power is a myth, perpetuated by the pseudo-capitalism we have in this country.
      • Re:Green Indeed (Score:2, Insightful)

        by Ignignot ( 782335 )
        "Cheap" nuclear power is a myth, perpetuated by the pseudo-capitalism we have in this country.

        And the idea of green energy is impossible - wind and solar take up too much space to be viable. Ireland is converting as much area as possible into wind power and they are going to generate 10%. To have enough solar power to replace all energy needs we would need to cover someplace the size of Colorado with panels, and replace an area the size of New Jersey every year. All hydroelectric is already in use.
        • Re:Green Indeed (Score:3, Informative)

          by rednox ( 243124 )

          Many green energy solutions can be implemented in a decentralized manner, instead of in huge projects like you mention. Installing them in this manner could make use of space that could not otherwise be used for energy generation.

          Covering your house's shingles with solar panels would be expensive, but this could provide for [nrel.gov] much of the electrical needs [exeloncorp.com] of your household. For about $14,000, you can buy 24 165w Sharp 1575mm x 826mm solar panels [solar-electric.com], and save about $500 a year on electricity.

          A 20m tower with a [bergey.com]

      • Re:Green Indeed (Score:5, Informative)

        by CSharpMinor ( 610476 ) on Saturday July 10, 2004 @08:25PM (#9663748)
        I would be alarmed by that article if most of it were even misleading instead of simply false.

        The Price-Andersen Act simply allows the government to act as an insurance broker for nuclear power plants. The plants PAY for the insurance, and it only covers small accidents-- maximum liability for the government is something like $10 million. Furthermore, the act allows for priave companies to step in to take over the insurace after a period of some years-- something that private companies have indeed done. (The PA Act has actually made taxpayers money, as plants have paid out more than they have received, just like any successful insurance company. So it doesn't count as subsidy at all.)

        As for the "$66 billion" figure, that's even worse. They mean, "The military has spent $66 billion researching nuclear reactors for their own use between 1948 and 1998."

        Nuclear power does receive some subsidies, but not many-- especially compared to wind and solar, which are absolutely not cost effective. Coal, the second cheapest method of generating electricity (next to nuclear, unremarkably), receives over a billion dollars a year from the federal government just to support miners who have developed black lung disease. Oil receives billions as well. In fact, anything you can name receives more money than nuclear.

        Nuclear power is not popular, and politicians know it. If nuclear power really received these nefarious subsidies, every senator in Congress would be biting at it so s/he could claim to be "fighting for safer power." Do you really think any member of Congress could pass up the chance to guarantee re-election?

        (PS-- solar has some nasty hazardous waste products. The panels themselves are about as toxic as cyanide, as measured by LD50, and generous amounts of arsenic are produced as a result of the doping process of the silicon panels. Furthermore, when solar panels electromigrate, that's it-- if you try to recycle them, you end up using more energy than you got out of the panel in the first place. Those shiny toxic squares have to be thrown away.)

        IANANT,BIASTGMOLAARR (Not a nuclear technician, but I am studying to get my operator's license at a research reactor.)
        • Re:Green Indeed (Score:3, Informative)

          by FirstOne ( 193462 )
          "I would be alarmed by that article if most of it were even misleading instead of simply false."

          It would be nice it you got your facts straight... Most of your statements are outright lies !!

          "The Price-Andersen Act simply allows the government to act as an insurance broker for nuclear power plants. The plants PAY for the insurance, and it only covers small accidents-- maximum liability for the government is something like $10 million. Furthermore, the act allows for private companies to step in to take o

    • Isn't the East Coast mostly on coal and oil power? I'd be doing ANYTHING possible to get off of coal power, even if it's just a tiny little 10mw dent.

      I'm thankful all the time that I live in British Columbia, with our abundant hydroelectric power.

      • Isn't the East Coast mostly on coal and oil power? I'd be doing ANYTHING possible to get off of coal power, even if it's just a tiny little 10mw dent.

        The East Coast of the US also imports a whole lot of power from Quebec. I would assume this is mostly hydroelectric.
      • Hydro is so abundant here that we only have to import 10% of our power needs! =)
        That's right, we're power importers in BC. We're just lucky that BC Hydro can literally turn on and off the generators with next to no cost. This lets them, and eventually us, benefit from high priced exports when there's peak power demand elsewhere, balanced against larger amounts of relatively cheap imported power at off-peak times.
        I guess my point would be, don't be too proud of power being mostly "clean" hydro - it ma
    • Nuclear still puts out power at under three cents a kilowatt hour
      No, that's three cents per kW/h plus tax money. Nuclear is subsidised due to it being the nice freindly side of the bomb. In Britain, they opened up the books of British Nuclear Fuels to public scrutiny years ago, and the British plants certainly cost a lot to run.
      You would think it's cheaper to run a water wheel
      Scale counts for a lot.
  • by vmalloc_ ( 516438 ) on Saturday July 10, 2004 @05:29PM (#9663124)
    (Sorry, a tad unrelated, but I haven't found anybody that would know the answer to this yet).

    I'm making a radio broadcasting book, and I had a question about the New York water system that I never quite addressed.

    It's on this picture: http://www.usinternet.com/users/kyledrake/newyork- radio.jpg [usinternet.com]

    It's an old field strength determination from the 1920s. See the water area below the taller buildings with the '20' strength? Is that water salty, fresh, or a mix of both (salty-leaning, or fresh-leaning even)? The reason I ask, is because if it is salty, it shows with more signifigance the blocking ability of structures (as salt water is very conductive).

    Thank you!

    • in fact, the salinity goes up to poughkeepsie (the river to your left, the hudson) a 2 hour drive away... during low rain periods, such as the summer, the salinity creeps up even higher than that, but poughkeepsie is generally considered the point where brackish water gives way to fresh water

      on the right is the east river, which leads to long island sound (all ocean) and behind you, from the picture's perspective, is the atlantic ocean (all ocean)

      that spot you are talking about is between the tip of manhattan and governor's island, al ocean water, all the time
    • I highly doubt the salinity of water bodies has anything to do with the aboveground attenuation of radio signals. unless you're under water, why would it make a difference.
      • by vmalloc_ ( 516438 ) on Saturday July 10, 2004 @06:38PM (#9663392)
        Groundwave is a very important factor at lower frequencies, because low frequencies 'travel' along the ground (a natural property of their longer wavelength). The more conductive the ground is, the farther the signals will travel (based on the output wattage of course).

        For very high frequencies, like Wi-Fi, the groundwave is considerably less important. With Wi-Fi, the line-of-sight is the most important factor. So you're right if you're thinking about higher frequencies, which are where most of the modern radio systems are operating. My book is about mediumwave (AM band) broadcasting however, so concepts like groundwave still play a pretty important part.
  • Interesting... (Score:5, Interesting)

    by Noryungi ( 70322 ) on Saturday July 10, 2004 @05:34PM (#9663151) Homepage Journal
    There is only one other project like this that I have heard of. It's in France, and its the Usine de la Rance [www.edf.fr].

    The Usine Maremotice de la Rance is based on the French equivalent of the St Lawrence Bay. This is a place where the tide amplitude is one of the highest in the world.

    At low tide, the sea truly is miles away from the shore. I have been there, and it's amazing how far away the ocean can go... and how fast it can come back. Saint Malo, the nearest city, was actually (a few centuries ago) an island at high tide, and people had to wait for the low tides to cross over the sand to the city.

    The 'Usine' itself has been pretty successful, and provides 'clean', tide-based electricity to Saint Malo and other cities, but its ecological impact has been underestimated: the Rance, which used to be a clean river is now severely clogged with mud and silt that are not evacuated by the tide, to the detriment of wildlife. Many bird and fish species have left the river for others or have died off completely.

    I hope the company that will build the New York project has taken this data into account for its project (which seems to be the case).
    • by debest ( 471937 ) on Saturday July 10, 2004 @06:39PM (#9663397)
      There is also a tidal-power plant in Annapolis Royal, Nova Scotia [nspower.ca]. Like these ones, it was built as a test of the technology. Only it's already been around for 20 years.

      It puts out 20 MW, and is on the Bay of Fundy, where you will find the truly highest tides in the world.

    • ...St Lawrence Bay. This is a place where the tide amplitude is one of the highest in the world.

      Don't you mean the Bay of Fundy? [bayoffundy.com]
    • Highest tides (Score:3, Informative)

      by GuyFawkes ( 729054 )
      sorry, st malo doesn't have them, two or three places in the world can argue this one, there a place in canada I think, fundy / funday bay or something, bristol channel, etc... they all get about 16 metres at peak....

      very close to st malo is the ras de sein, which can lay claim to having some of the fastest tidal currents on earth, eg 9+ knots (real fun in a 30 foot sailing boat with a max hull speed of 7 knots, even more fun when wind and tide oppose each other... lol

      the bristol tides run up the severn,
    • At low tide, the sea truly is miles away from the shore.

      And how, pray tell, is this feat accomplished?

      Actually this reminds me of one of the stupid practical jokes the more experienced hands would pull on the 'boots' (newcomers, green-behind-the-ears, etc) when I was in the Coast Guard. They were so used to finding various lines (ropes) for different things-- anchor lines, mooring lines, whatever, that when told to go find a shore line, they'd start looking for rope. The laughter would always come

  • Great Idea, but.. (Score:5, Insightful)

    by phamNewan ( 689644 ) on Saturday July 10, 2004 @05:36PM (#9663160) Journal
    It also highlights the difficulty that all green based solutions have, nature. Solar power has cloud problems, windmills will lack wind, and hydro-electric dams face droughts.

    None of the green energy sources can provide the reliable energy that modern society demands. While this one will at least be very predictable, it will only be able to generate power when the tides are right, and that has no relation to peak power usage times. Sometimes the timing will be right, but the rest is wasted.

    This will probably get me mod'd Troll, but nuclear power is the best available option, and since we cut research into making it better, we are now behind France (the horror) in nuclear technology.

    Despite all the concerns, nuclear is the best choice we have until we can finally find a more efficient way to generate electricity without using steam.
    • Re:Great Idea, but.. (Score:5, Informative)

      by Poingggg ( 103097 ) on Saturday July 10, 2004 @05:59PM (#9663248)
      Sorry to disappoint you, but nuclear power also uses steam, generated by nuclear fission. I won't go into the environmental risks of nuke power, cause I will be modded troll for it (happened in earlier posts), but in the total cycle uranium and plutonium go through from mining (just uranium) to waste product, the only stage that is 'clean' is when it's used for generating electricity. Everything before and after is heavily polluting and does not even outweigh coal. Of course the nuclear industry only shows you the energy-production stage, that, indeed, is rather clean.

    • There are lots of ways to "cache" power for later. Batteries, supercapacitors, and flywheels are all viable options. Wind power is having a small surge in popularity recently, thanks to advances in ways of buffering the power so that it doesn't wreck the grid.

      That said, I totally agree with you about nuclear power. Modern reactors are much safer and produce much less waste than reactors of the past. Some reactors can use weapons-grade plutonium, which provides an easy solution to the problem of decomi

    • by medelliadegray ( 705137 ) on Saturday July 10, 2004 @06:12PM (#9663296)
      you are correct that solar may have cloudy days and turbines can face calm days.

      but just think for a moment--solar still generates SOME power on cloudy days. turbines can produce some energy as well on the days that arent ideal. i dont know at what point turbines become useless, but it has to be a pretty calm day.

      The point is it mitigate your resources in many locations. if every roof had had solar panels over their shingles, and every telephone/power pole had a mini turbine ontop of it, then i ask you--how often is it pitch black and dead calm out EVERYWHERE--night time?--even then the clam is usually localised.

      clouds move, and so do wind patterns. energy can be shipped from the sunny spots to the cloudy, and so on and so forth.

      Excess energy from all of those turbines and roofs---well if we ever get to a hydrogen economy--there wont be such a thing--it will go toward electrolosis for hydrogen production.

      speratic nuclear plants can pickup the energy needs of nighttime hours and such--hell if it was a true hydrogen economy, people would just use some hyrdogen to make their electricity, also, maybe we'd see an end to the excessive use of streetlights littering towns and cities. Their great untill about 10:00 pm, but cmon, after that its an annoyance.

      nuclear has and will continue to have its place, but in my opinion it should be used as a backup for when the more "green" methods cant put out enough juice.

      • Excess energy [...] will go toward electrolosis for hydrogen production.

        That's called peak shaving. BTW, isn't the FA about tidal power? When was the last time the tides failed to come in (or go out)?
    • It's too bad that nuclear power provokes such a backlash of emotion that thoughts like the above poster's aren't giving considerable weight.

      The fact is, nuclear power can and will solve all our our energy problems. The problem of nuclear power is merely one of "waste" and what to do with it. The upside to this is that with the power of nuclear energy, we could be launching waste out of the planet within a decade.

      Non-renewable resources drying up should *not* be an issue, but they are because of the fear o
    • None of the green energy sources can provide the reliable energy that modern society demands.

      Hydroelectric power aka dam power.

      And while these typically need speical circumstances to be viable, they are one of the ways that you can have green reliable power.

      But like most people here I agree that nuclear is the way to go in the long run. The Japanese have that neat little one that's about the size of a large bus if I remember correctly. Perfect for small towns.
    • ...nuclear is the best choice we have until we can finally find a more efficient way to generate electricity without using steam.

      Why would we care about generating electricity without steam? It's not like we're going to run out of it.
    • Re:Great Idea, but.. (Score:2, Interesting)

      by zogger ( 617870 )
      Nuclear is a big and powerful method to generate a lot of power, and to insure that huge vast sums of money in the form of never ending profits remain in a small handful of corporations pockets. It's also quite a juicy target, therefore a major security risk, plus, that pesky waste stuff, that hangs around hot longer than recorded human history to date.

      If you are more interested in having energy decentralised, with millions of potential islands instead of a few hundred, with the costs (and profits) decen
    • It also highlights the difficulty that all green based solutions have ... windmills will lack wind

      Real life provides few magic bullet solutions. Coal/Oil/Nuclear base load units all have the problem that they only work well with sustained static loads with the same power factor, so compromises are used there too. It may surprise you that such things as pump storage hydro are mainstream solutions to using that base load when it is not in demand, and giving that extra burst of power when it is needed. In

    • None of the green energy sources can provide the reliable energy that modern society demands. While this one will at least be very predictable, it will only be able to generate power when the tides are right, and that has no relation to peak power usage times. Sometimes the timing will be right, but the rest is wasted.


      This is something that needs to be underscored; what is even worse is the magnitude to which green energy sources fall short. It's a myth; it's outright LIES at worst. Hydrogen is not an en
  • by Esben ( 553245 ) on Saturday July 10, 2004 @05:54PM (#9663222)
    Isn't really very much... The company I work for allready sell windtubines at 3MW. Other companies
    sell even bigger ones (4.5MW I believe.)

    These turbines takes a lot of manpower to keep running. Stuff needs to be repaired every month or so. I can't start to imagine the problems one would have when trying to put them down into the salty waters of East River!

    But then again: One have to try and get the technology running. That was how the windturbine-buisness got started, too, and that is big buisness these days.
  • East River (Score:3, Funny)

    by No Tears In The End ( 452319 ) on Saturday July 10, 2004 @06:20PM (#9663324)
    At least the power coming from it will be environmentally friendly, even if the water isn't.

    NTITE
  • Do not send prototypes to Pakistan for testing. =)
    ...the project was delayed when his only prototype of the turbine was lost several years ago after being sent to Pakistan for testing. "I'm still not sure how you lose a package that large," he said during a presentation to a group ...

    I wonder why they went that far for testing anyway?
  • dont wan't to be dredging things up from the river bed do we?
  • by beforewisdom ( 729725 ) on Saturday July 10, 2004 @07:21PM (#9663557)
    It can act as a means of disposal for the mob.
  • wow, finally, killing two birds with one stone, solving NY's power consumption and getting rid of that green glow in the east river.
  • by sbaker ( 47485 ) * on Saturday July 10, 2004 @07:47PM (#9663629) Homepage
    In order to extract energy from the water, it's gotta slow it down somewhat. When you do that, you cause sediment to settle out prematurely where it never settled out before. That can change the direction of flow, causing erosion in new places and deposition in others - maybe cause loss of habitat for some animals and plants.

    There isn't *ANY* power generation system that doesn't have some kind of impact. The issue is whether this has a more acceptable impact than the other ways to get that much power.

    The problem I have with these projects is that if you spent the same amount of money on energy saving plans, you'd end up with the same results - but with LESS environmental impact - not more.

    For example, I live in Texas where a large fraction of everyone's electricity bill is paying for airconditioning and heating. By spending about an extra 5% on the price of my house, I ended up with about three times better thermal insulation factor compared to a typical Texas home. As a result (since A/C and Heat are such large fraction of electric bills here), it's no suprise that my electric bills are about half what my friends and neighbours are getting for similar sized houses. (My house is built with this stuff: http://oikos.com/companies/grnblock.html)

    Crunching the numbers, my additional 5% up-front cost is repayed in about 5 years...and the house should last at least 25 years so this is a really good deal.

    However, getting people to pay that 5% up-front cost is HARD. (Why else would so few houses be built that way?)

    But what if the government or the electricity generation companies paid you to add that extra insulation and took the cost of it back from your fuel bill savings in the form of a tax of some kind? An initial outlay of $20M would halve the electicity consumption of about 5,000 houses like mine. That's about the same as building a 3.5MW powerstation. Not as good as the 10MW one that they are planning to build in NY for $20M - but mine lasts for 25 years without maintenance, labor, etc - has not technical risk and has a really GOOD effect on the environment by reducing the net amount of electricity that has to be generated.

    That's just one example - I'm sure there are others.
  • TANSTAAFL (Score:4, Insightful)

    by ZorbaTHut ( 126196 ) on Saturday July 10, 2004 @08:10PM (#9663693) Homepage
    There Ain't No Such Thing As A Free Lunch.

    Also known as conservation of energy.

    The wind-turbine people said "oh, it couldn't possibly make any difference." Now - surprise - there's some evidence wind power screws with wind patterns.

    The tidal-power people are saying "it couldn't possibly make any difference" and give figures like "the entire planet's energy needs could be filled twice over by the ocean's tides". Except that actually getting that much energy out of the ocean would involve, oh, stopping the tides, and I don't think anyone's claimed that won't cause serious problems.

    So this generator produces 10MW, does it? Where's the power coming from? Answer: it's slowing down the river. Will this cause future problems? I have absolutely no idea, but it's something that would be nice to find out.

    Whenever someone comes up with a source of untapped power, think for a second and figure out where the energy is actually coming from.
    • Think about where tides come from. If you can stop _that_, then you're really on to something.

      I'm curious what evidence you have that wind power 'screws with wind patterns'?

Algebraic symbols are used when you do not know what you are talking about. -- Philippe Schnoebelen

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