Another Electric drive small sailboat

Discussion in 'Electric Propulsion' started by Artem Klochko, Jun 26, 2020.

  1. Artem Klochko
    Joined: Dec 2018
    Posts: 44
    Likes: 16, Points: 8
    Location: Ukraine, Dnipro river

    Artem Klochko Junior Member

    Run at 1.8 kW video:


    Boat and drive specs:
    3 kW electric motor QS 138
    Kelly controller KLS 6022H
    36V 180Ah Lithium battery, battery topic by this link
    Boat weight 1800 kg
    Boat LWL is 6.5 m
    Electric drive weight including battery: 55 kg

    Discharging:
    Clear weather tests:
    1.8 kW - 5 knots
    1 kW - 4 knots
    500 W - 2.7 knots
    200 W - 1.6 knots

    Upwind 15 knots, 30 knots gusts:
    1.8 kW - 3.5-4 knots

    1 kW run - 6+ hours at battery.

    Charging:
    Shore power - 1 kW charger, 6 hours from "empty" battery state
    Solar charge - 250W, 5 summer days from "empty" battery state. Charge from PV using MPPT controller.

    Cost of all electric things: wires, connectors, fuses, electric motor, mppt controller, motor controller, electric drive, solar panel and lithium battery ~ 3500 USD
     

    Attached Files:

  2. Artem Klochko
    Joined: Dec 2018
    Posts: 44
    Likes: 16, Points: 8
    Location: Ukraine, Dnipro river

    Artem Klochko Junior Member


    Video from drone
     
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  3. alan craig
    Joined: Jul 2012
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    Location: s.e. england

    alan craig Senior Member

    Excellent! And if you chose to remove the sailing rig and add three or four more solar panels it would probably work well as a full solar boat.
     
  4. Artem Klochko
    Joined: Dec 2018
    Posts: 44
    Likes: 16, Points: 8
    Location: Ukraine, Dnipro river

    Artem Klochko Junior Member

    Thanks! Yep, it may work as full solar boat, but boat owner don't want to remove sails.
    This is first boat I converted to electric drive except my boat.
     
  5. Dejay
    Joined: Mar 2018
    Posts: 520
    Likes: 83, Points: 28
    Location: Europe

    Dejay Senior Newbie

    Wow really nice, thanks for sharing a real life build! This seems to be in a good sweet spot, not too expensive and battery doubles for propulsion and hotel power.

    For a sailboat regeneration from the prop while sailing would also be interesting. Does your motor controller support that?

    Removing mast would negatively impact how comfortable the motion is right?
     
  6. Artem Klochko
    Joined: Dec 2018
    Posts: 44
    Likes: 16, Points: 8
    Location: Ukraine, Dnipro river

    Artem Klochko Junior Member

    Dejay, thanks! Motor controller support regeneration, but for such small boat regeneration can give very small amount of energy, like 50W at 5 knots and will produce a significant drag. So I suggested boat owner to use a folding prop and he used it. For sailboat displacement 3000+ kg regeneration has the meaning.

    Boat owner don't like to remove mast because he like sailing. At this boat electric motor is auxiliary engine, main is sails.
     
    Last edited: Jun 28, 2020
  7. Artem Klochko
    Joined: Dec 2018
    Posts: 44
    Likes: 16, Points: 8
    Location: Ukraine, Dnipro river

    Artem Klochko Junior Member


    Official video from "Interparus" company about this boat. Voice language is russian, but you may turn on subtitle translation. Enjoy watching! :)
     
  8. seandepagnier
    Joined: Oct 2020
    Posts: 8
    Likes: 1, Points: 3
    Location: the sea

    seandepagnier Junior Member

    You forgot the most important detail is the propeller. Inboards are terrible efficiency because the propeller is too small. Almost all sailboats today have very low efficiency of propeller alone is less than 30% and the stuffing box wastes a lot too.

    I have a larger boat (33ft trimaran) and I can motor 2 knots using 120 watts. I have a large carbon fiber propeller and built my own mppt:
    solar powered boat https://hackaday.io/project/174537-solar-powered-boat

    My electric motor ($45) total cost is $250. With 4x 50 watt solar panels I do not draw from battery while motoring. Boat is sailing today faster than the wind speed so not much reason to motor more than 2 knots.
     
  9. Artem Klochko
    Joined: Dec 2018
    Posts: 44
    Likes: 16, Points: 8
    Location: Ukraine, Dnipro river

    Artem Klochko Junior Member

    Hi seandepagnier,
    Thanks for sharing your experience with us!
    I know large prop have better efficiency than smaller one, but monohull shape do not allow to install very large prop diameters.

    Your approach is very interesting, but it will not able to move boat out of danger in bad conditions. Kaplya was able to move in 15 knots wind, this is really help at Dniper river which have locations with some underwater rocks. Boat owner decided to better to spend some extra money for motor and have ability to move out dangerous area if wind direction is not profitable.
     
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  10. srimes
    Joined: Sep 2008
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    Location: Oregon

    srimes Senior Member

    Very nice! And the price is very good too.

    I agree that it's important to have power for safety in many situations, like crossing a river bar.
     
  11. seandepagnier
    Joined: Oct 2020
    Posts: 8
    Likes: 1, Points: 3
    Location: the sea

    seandepagnier Junior Member

    Then why not have high efficiency outboard with large prop for longer range in calms wind, and high power inboard for inefficient maneuvering? the outboard uses less than half the power so this is a huge range difference.

    You need only 2-3 boat lengths width to tack and so it's not a problem in a river. In rivers and canals you can tack against the wind, I have done this many times tacking in river bars several times, you don't need to power for that. A lot of people think you do, but they just don't have experience and don't know the truth. One day I tacked 99 times against 25 knot wind in a canal covering 15 miles as I had a favorable current.

    With an electric motor or sculling oar you can navigate anywhere under sail on a small boat because the motor gives enhanced control and prevents missing tacks from wind shifts and keeps you out of danger while using very small amount of energy since the power is still from the sails. This is very bad for engine to stop and start it all the time and so a clear win for electric power, and you don't need much of a battery bank.

    Almost all boat accidents are from powerboats. Further many sailboats are lost because people relied on engines that failed. I've been to 30 countries and never used any engine. So I don't think need power to get out of danger, it can also get you into danger and we are all in danger from too much power consumption.
     
  12. srimes
    Joined: Sep 2008
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    Location: Oregon

    srimes Senior Member

    About half the time I cross my local river bar there isn't enough wind there to sail, and there can still be a decent swell and current requiring more than 2kts boat speed. And who wants to motor at 2 kts? Most sailors won't bother sailing that slow, opting instead to fire up the motor. Don't get me wrong what you made is cool it just isn't enough power for most people.

    With that size prop could it work as a wind turbine too? Could have something there...
     
  13. missinginaction
    Joined: Aug 2007
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    Location: New York

    missinginaction Senior Member

    These are all great ideas and I'm all for "outside the box" thinking. Finding a way to lower charging times (short of covering the boat with panels) when away from shore power will go a long way towards making these types of systems more attractive to ultimate retail buyers.

    If it were me I'd take something like a Honda EU1000i and a 40 amp charger (about 500 watts) along for the ride. I could charge my batteries up in a few hours at night, assuming a 50% discharge rate. A 5 gallon can of gas would run that generator for better than three days, non-stop or for 10 days, 8 hours a day. I realize that a generator/charger doesn't get you completely off fossil fuels, but it's a lot better than the fuel consumption on my power boat.

    Thanks for posting, I enjoyed reading through the thread,

    MIA
     
  14. seandepagnier
    Joined: Oct 2020
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    Location: the sea

    seandepagnier Junior Member

    If there is 2 knots of current this will produce enough apparent wind to sail off of and remain in control enough to avoid hitting things while the current takes you where you need to go. I have navigated rivers when the flags were limp on the shore but I was able to tack and move faster than the current. If you want to go against the current.. there are clever ways of doing this as well without using power, but maybe better on a different thread.

    I have entered/exited across many river bars. There is generally a tidal current that must be favorable and when it is you don't even need wind; when it is not, you must wait unless you can overpower it with the sails. It doesn't matter because once inside the boat will wait as well, so it's not wasting time or anything like that. Where is there not wind to sail half the time? I don't think that place actually exists in this world and is also at a bar entrance. I have calculated from sailing in pacific, indian and atlantic oceans, there is wind to sail 95% of the time.

    Who wants to motor 2 knots? To me this is fast after many years with a sculling oar. Motoring is generally for navigating in harbors not for covering actual miles anyway, so the speed is not really much of an issue. I prefer to scull in cold weather since the battery is more limited in winter with only solar input, but also because it keeps me warm.

    If I can go 2 knots at 120 watts, then 3 knots should take about 200-240 watts, and 4 knots 400-500 watts. This is less than half what other boats are using. I've played with trolling motors and that takes 240 watts to go 1.8 knots using a typically sized propeller giving the typical power consumption.

    I guess a few slaves is better than having hundreds, so I can commend any efforts to use less. Anyone with the privilege to cruise around on a sailboat doesn't really have the moral ground to use any kind of fossil fuels at all considering that they just aren't needed and never were. I have cruised around the world for 10 years with no fuels. I am cooking also with a solar oven and the evacuated ones work even in wind and freezing weather. I need to set a timer because I keep overcooking things.

    For this non-essential activity: if everyone has significantly more power than what they can produce themselves, the future of the world is bleak for everyone. This is a form of injustice to most of the people in the world who will never get to sail anywhere. It is sure looking this way and the predictions are worse all the time. If I covered my boat with solar it would go 5 knots, but I don't want to do this either, maybe you do. If I spend $4000 on a battery instead of $60 (for 300 watt hours), I would be able to motor for 200-300 miles but there is also a limit on how many batteries everyone can have. To say "it just isn't enough power for most people" I would reply that it has to be; anything else is an addiction which has terrible inevitable long term consequences.

    In any case feel free to agree/disagree with me, but my original point is that almost all electric drives I have seen (at least a few dozen) use the same inboard propeller and shaft which was engineered to be used with an engine, and they did not care about efficiency very much. It is a compromise because the engine is very heavy is must be mounted where it is and therefore cannot transfer power to where a huge propeller can actually be located. Before carbon fiber, large propellers were also very heavy and expensive, and even bronze is not nearly as efficient especially in high-aspect ratios. They made something that pushed the boat hull speed for a long way and fuel was cheap so not much reason to change the design, but it's not really suitable for anyone who cares about efficiency.

    Electric motors are much lighter weight for their power, and are capable of being used completely differently. Our propellers with electric should approach 90% efficiency, because they can. Cutting battery and solar in half saves a lot on cost. It's better to have less battery weight, and less solar occupying deck. So I feel it's worth it to have a huge propeller and gear system and we should all forget about inboard drives.
     

  15. srimes
    Joined: Sep 2008
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    Location: Oregon

    srimes Senior Member

    You're clearly a far more experienced, and far better sailor than I. You also have more time to spend sailing. Like many, I have a day job and limited opportunities to get out on the water.

    Maybe my location is special, but right now the wind stations either side of the bar report 1 and 2 kts, while the offshore bouy reads 20 and a few more miles will get you to 29. These are common conditions here. Yes there will be moments of wind but they aren't likely to fit with a my schedule. You may be comfortable sailing across in a fluky 1-2kts, but I ain't. I'll fire up the 9.9 for 1-2 miles each way no worries.
    upload_2020-10-19_10-18-32.png
     
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