Build a power boat, power by wind. PART II

Discussion in 'Press Releases' started by windboat, Jul 31, 2011.

  1. kerosene
    Joined: Jul 2006
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    Location: finland

    kerosene Senior Member

    Agree with the other post - but I would be curious of what kind of usage assumptions you made for the diesel comparison?

    My reply was for the other post that suggested that even moderate efficiency gain would be beneficial. Which it is not if other aspects of the design are forced to be less ideal.

    but in regards to your concept - Just answer this: Who is going to buy a 16m (52ft) boat that:
    -Needs periodical replacement of batteries for thousands and thousands of dollars (~$15,000 is realistic price).
    -has effective range of 14 nm (at what, 5 knots?)
    -has potential recharge time of days if not weeks depending on conditions

    you could probably add: compromised seakeeping compared to similar sized conventional boat and higher initial purchase price compared to conventional.

    Please answer the main question above and address the points listed.
     
  2. windboat
    Joined: Jul 2011
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    Location: Taipei ,Taiwan

    windboat Junior Member

    search on website"how many CO 2 emissions" , and the diesel boat use 5000 L per year
     
  3. Leo Lazauskas
    Joined: Jan 2002
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    Location: Adelaide, South Australia

    Leo Lazauskas Senior Member

    The boat with the vertical axis wind turbine is really silly.

    Fixed pitch VAWT are not self-starting and they can have very significant problems with vibrations.

    To me it looks like the toppling moment of the turbine will snap the shaft at the bottom.

    I hope nobody wastes real money on this project as it stands.
     
  4. kerosene
    Joined: Jul 2006
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    Location: finland

    kerosene Senior Member

    Lets see how that 5000 liters compares to what your boat can do.

    5000l * 800g/l (density) * 200g/kwh(diesel effciency) = 20,000kwh

    so we get 20,000kwh from 5000l diesel. How many cycles on the batteries does that equal.

    your battery is 108kwh nominal. Much over 50% depth of discharge will kill the lead acid batteries in no time but i will give you 66%. Also in these calculations I am not counting in any losses in your electric power train (at least 10-20% loss)

    20,000kwh/(108kwh*0.66)=280.6 cycles

    so your windboat would have to drain the batteries 280 times to equal same amount of energy as the diesel numbers you suggested. As it is likely to take days to charge your batteries it is impossible to use your boat that much.

    More sensible numbers for your boat would be a cycle a week. Which would be ~70kwh/week ~3600kwh/year. That would equal 900L of diesel/year.

    I am not penalizing you for less optimal boat shape that would probably make significant difference in hull efficiency in favor of the diesel.

    Look Windboat, I am not a "pro diesel" person. But I am pro using the common sense and against new solutions that are worse than current ones. I have only high school level math experience and I can easily test your claims in the right ballpark - and they don't make any sense. You should do the same to avoid ridiculing yourself.

    You still have no addressed my previous post.
     
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  5. windboat
    Joined: Jul 2011
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    Location: Taipei ,Taiwan

    windboat Junior Member

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