energy recovery while sailing

Discussion in 'Hybrid' started by kriz, Dec 1, 2009.

  1. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 494, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Considering the scope of a project and the size you're suggesting, you'll need a staff to coordinate the various efforts of the design teams. When you have craft with 8 figure price tags, there's so much to do, that no single person could possibly be expected to handle it all.

    It would be a wise decision to contact an NA, preferably one the specializes in traditional, period and replica vessels of this size. You'll very likely need to develop a none profit organization or possibly a full blown corporation, elect officers and divide up the tasks and duties just like any other business. With this accomplished you can portion off a section of staff to investigate energy options.

    The debate with Kistinie isn't much of a debate, frankly. This particular poster is held in very poor regard by other forum members, an justly so.
     
  2. kistinie
    Joined: Aug 2007
    Posts: 493
    Likes: 8, Points: 0, Legacy Rep: -74
    Location: france

    kistinie Hybrid corsair

    Hi Kriz !

    my need is basically the same.
    I guess we are a lot sharing this goal that appears to be very accessible even with trashes and recycling.

    We should split the problem in small compatible parts, make it , join the bits, trying all combinations for many different needs, find best combination.

    Propeller
    Rotor
    Stator
    Rectifier/Controller
    Batteries
    Windnill
    PV solar



    Good will joined should give good things

    One can be documentation
    Two, prototype of all kind of solutions
    Three, Size standards.

    3 months for each phase
    Source of materials : Used as much as possible.
    Made to last as long as possible.
    Cop 1 or higher for each part (.95% said 1 by approximation)
     
  3. FAST FRED
    Joined: Oct 2002
    Posts: 4,519
    Likes: 111, Points: 63, Legacy Rep: 1009
    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    "trying all combinations for many different needs, find best combination."

    If the concern is a sailing vessel, the only time drag devices should be deployed is when hull speed is reached.

    Don't know about your experience but on ocean cruising I have done its RARE. But great when it happens.

    The reason is when huge excess power (BIG WINDS) is available , most folks wont press the boat to save the loading , and to ease the motion.

    To loose a K on a boat that travels 5K is a 20% loss , and will extend the transit time by 20%.

    More food , more water, and a crappy experience of sailing at a sub par speed. For watt?

    FF
     
  4. capt vimes
    Joined: Apr 2009
    Posts: 388
    Likes: 14, Points: 18, Legacy Rep: 247
    Location: Austria

    capt vimes Senior Member

    another question:
    many yachts are actually featuring a fixed wing prop... so you will have drag from that prop no matter if its turning or not...

    the question is now what is producing more drag?
    the prop fixed with the gearbox in reverse or a turning prop which drives a generator?

    in my opinion the differnce might be so small as to be neglected and therfore i see no reason why i shouldn't run a generator with the prop.

    if folding props or similar are used... not to argue about that - once you drive a gernerator with the prop you will have a considerable amount of drag-increase.
     
  5. apex1

    apex1 Guest

    There is a wrong assumption here! The prop commonly is freewheeling, not turning the gear!

    And of course every 1KW of electricity you produce with a dragged prop equals to a min. of 1,2KW of power in reverse!

    simplified.............
     
  6. capt vimes
    Joined: Apr 2009
    Posts: 388
    Likes: 14, Points: 18, Legacy Rep: 247
    Location: Austria

    capt vimes Senior Member

    thank's...
    it realy is simple... ;)
     
  7. Joakim
    Joined: Apr 2004
    Posts: 892
    Likes: 52, Points: 28, Legacy Rep: 422
    Location: Finland

    Joakim Senior Member

    Probably they have about the same drag. Here is a paper which compares the resistance of a propeller fixed or freewheeling at different amount of friction (torque). For a 12x6 3 blade propeller the drag at 3 m/s is ~150 N and "freewheeling" with 1.92 N/m friction it is ~100 N. Maybe you could get almost 200 W of power out of this?

    http://strathprints.strath.ac.uk/5670/1/strathprints005670.pdf

    Thus it would make sense to use a propeller as a generator rather than keep it fixed. But both options are real brakes compared to a folding propeller or even to a truly freewheeling propeller.

    A sailboat where you would likely see a 12" propeller has typically far less than 1000 N drag at 3 m/s. Thus the drag increase is more than 10%.
     
  8. kistinie
    Joined: Aug 2007
    Posts: 493
    Likes: 8, Points: 0, Legacy Rep: -74
    Location: france

    kistinie Hybrid corsair

    Great document Joakim
    Thanks

    It would be nice if we could find propellers power curve for positive torque (motoring) and negative (regenerating).
    So it does 4 quadrant with 3 only needed as regeneration going reverse is not very useful (to the exception of some prao having no fix head and tail)

    Does this already exist from manufacturers or does this measurement remain to be done ?

    First curve i'd like to find is the Archimede screw that seems to have a good potential to be efficient for the 4 quadrant but some other design could be even better ?
     
  9. kistinie
    Joined: Aug 2007
    Posts: 493
    Likes: 8, Points: 0, Legacy Rep: -74
    Location: france

    kistinie Hybrid corsair

    Except on delivery where is get anything, i have the chance to mostly sail with light fast (sometimes uncomfortable) multihulls. This is the reason why regen is so interesting for my view of sailing, but i agree that for the moment this is not the most common type of ship, but i guess that you noticed the increasing trimaran choice when high performance is searched, military application first.
    Now above 7/8 K, speed you will loose for 1 Kw extracted is low, so very worth loosing !
     
  10. FAST FRED
    Joined: Oct 2002
    Posts: 4,519
    Likes: 111, Points: 63, Legacy Rep: 1009
    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    i have the chance to mostly sail with light fast (sometimes uncomfortable) multihulls. This is the reason why regen is so interesting for my view of sailing,

    I had a Hedly Nichol Voyager 45 built in then British Honduras during the mid 1960's.

    Today's cruising designs are only a bit faster . Our top speed was 14K in smooth protected waters with a snot of wind.

    In the ocean we only did 200 mile days on rare occasions 150nm was closer to a "good day".

    Slowing down to charge a battery was never contemplated.

    What could one possibly need all that electric for?

    Are you contemplating a steel fabrication shop while sailing with lots of welding?

    With all the very efficient electrical toys today a battery recharge should only be useful every 3 or 4 days when the engine is exercised.
    A GPS uses a smaller current draw than the flashlight I used to need to read the sextant.!

    FF
     
  11. apex1

    apex1 Guest

    Well
    you know,
    and I know,
    and veery many else know,

    our fuckin dumb corsair does´nt get it..
    It´s idiotic to have a 3 kw drag on a hull needing 3kw to top speed.
     
  12. kistinie
    Joined: Aug 2007
    Posts: 493
    Likes: 8, Points: 0, Legacy Rep: -74
    Location: france

    kistinie Hybrid corsair

    A 40' racer stand 1 Kw with almost undetectable speed lost, this is the truth of what happen here, in real life, on real boats like Vendée Globe race monohulls.
    The fact you disagree will not change this reality dear APEX
    Now, it it possible to do much worst solution than these, giving heavy drag and low amps just by using an improper propeller connected to a bad inefficient generator !
    I have one like this at home, same drag for 16Amp/12V and very boring to use, towed propeller going in the rudder when you miss a tack, sharks attacking the propeller...Ok as an emergency power source...only !
    What i am working on is not this thing of the past.



    Kiss ! (Tiny Of Course !)
     
  13. FAST FRED
    Joined: Oct 2002
    Posts: 4,519
    Likes: 111, Points: 63, Legacy Rep: 1009
    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    "Vendée Globe race monohulls."

    See many of them cruising in the Carib after crossing from Europe every year?

    Still waiting to know WHY? there is a need for soo much eletric soo much of the time?

    What on earth is the juice used for , your hair dryer?

    FF
     
  14. fcfc
    Joined: Feb 2005
    Posts: 780
    Likes: 29, Points: 28, Legacy Rep: 399
    Location: france,europe

    fcfc Senior Member


  15. kistinie
    Joined: Aug 2007
    Posts: 493
    Likes: 8, Points: 0, Legacy Rep: -74
    Location: france

    kistinie Hybrid corsair

    New product price is linked to production volume and R&D cost.
    On a larger scale production with competitors, cost will be very different although probably remaining high as we are in the nautical world
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.