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Thread: Heather and electric propulsion

  1. #71
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    Default Re: Heather and electric propulsion

    I do not profess to be any kind of expert, but i did run through a cost conversion for someone who was intending to go all electric. Cut the long story short, electric only was not 100% reliable enough for this persons needs, given open tidal waters to deal with. The next option was a diesel electric hybrid, that option could reduce the battery capacity somewhat, at the expense of more engine running hours. There is no cost benefit converting amps from a diesel generator into a battery to be used by an electric motor, far more efficient to run a diesel straight to the prop. After using the manufacturers guides on battery life, it became clear that the cost of battery replacement every 5 years would far outweigh the cost of fuel and service items for a small diesel. Last i heard, he was talking of buying a new Farymann 7hp diesel, which engine is used extensively in generator sets.
    I planned a system for running under battery power for 6 hours out of every 24, but even then, the cost became an issue, where money spent on a good installation and sound proofing from the outset, means engine noise does not have to be too intrusive.
    I do not dismiss electric boats, they certainly can work for many people, but not for all people and situations; if you can work with the limitations, then look forward to seeing things progress.

  2. #72
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    Default Re: Heather and electric propulsion

    On the same basis you'd probably have to advise against sails. It's not really about the cost. I'm thinking trolling motor, coupla deep cycle batteries and whatever solar panels you can fit on her.
    Last edited by Phil Y; 11-17-2018 at 04:20 PM.

  3. #73
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    Default Re: Heather and electric propulsion

    I look forward to seeing you put this together Howard. I wonder, are you going to chose a motor strong enough to power through and into heavy winds and waves?

    It’s an interesting time for the electric drive debate. I have read or heard a few people say that a hybrid system is only applicable for intermitant use, like you are planning on doing. But had a friend take me through a NOAA research vessel one day (I forget the name of size 200+’, I’ll ask) It is powered with a Hybrid system like Marty specified for Heather. Two large Catterpiller generators and two large electric drive motors. Works in that scenario.
    Last edited by Matt young; 11-19-2018 at 09:22 AM.
    "Yeah, well, that's just, like your opinion man"
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  4. #74
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    Default Re: Heather and electric propulsion

    Hi Howard,
    There are a couple of electric propulsion experts in PT; Chris Brignoli and Matt Mortensen. They both work with the Shipwright's Co-op. They seem to know lots about the subject and they surely know the boat.

  5. #75
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    Default Re: Heather and electric propulsion

    Two things, to live with "electric" requires a considerable change in mindset (whether for propulsion or to live "off the grid") so the first decision is "can I make the big changes in my expectations"?? As an explanation, a friend of mine has an electric car with a range of 200KM (120 miles) - most people say "hopeless, its over 120 miles to the next city" However he and his wife are retired, so when they want to go touring they drive for a bit, have a cup of coffee/shop for half an hour while the car is plugged in and repeat - and they get all round NZ's South Island by this manner, covering some pretty big distances.

    The second thing is batteries, there are some interesting variations that are just becoming available to the market, one such battery that looks very attractive for propulsion is lead carbon, maintenance and gas free, at least as many charge cycles as Lipo's (possibly more) and 1/3 the cost of lipo's per KW/h

  6. #76
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    Default Re: Heather and electric propulsion

    Quote Originally Posted by john welsford View Post
    Bear in mind that Howard has quite recently spent 45 days on board, in very challenging territory, a boat with sails and oars only. I don't think that he'd be using the electric drive very much at all. We're not talking about motoring non stop from Port Townsend to the San Juans. More like manoeuvring in Marinas, occasionally getting off anchor in a tight spot, or motoring into MatsMats bay. ( I've been in there, and no you wouldn't normally sail in or out of there).

    As Howard says, Heather is mine to use should I be able to make it back to the area, and I'm hoping to. I don't think that I'd have her under power much, and even with a flat battery at 16 ft she'd be easy to move with a sweep oar.

    John Welsford
    The sweep oar (or a yuloh, maybe) sounds like a much better deal to me in so many ways compared to electric power...

    Watching this with great interest, though. Good luck, Howard!

    Tom
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  7. #77
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    Default Re: Heather and electric propulsion

    Following this thread out of a specific interest in electric propulsion.... because I am learning all I can with a view to building a hybrid system using much the same battery genset and motor as proposed in this thread, although with a large diameter 4 blade prop that can be lifted from the water when not used for propulsion.
    This is of course on a completely different kind of boat, so being mindful of certain limitations regarding prop diameter on Heather,I cannot help wondering if the change is at all a good idea.
    Seems to me that Heather has been designed and built around the diesel inboard .... there is the wheelhouse, the marvellously accessible motor, and then the forepeak accomodation with a spacious cockpit, all without the motor box appearing be intrusive. Also, the prop shaft and prop working well with rudder and keels.
    Now, had there been a cabin where the cockpit now is, and an after cockpit with a motor jammed in under it, there might have been good reason to change to electric, at associated cost of the exercise.
    Instead, a lovely little boat could end up as an experimental folly.

  8. #78
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    Default Re: Heather and electric propulsion

    Quote Originally Posted by Foster Price View Post
    The second thing is batteries, there are some interesting variations that are just becoming available to the market, one such battery that looks very attractive for propulsion is lead carbon, maintenance and gas free, at least as many charge cycles as Lipo's (possibly more) and 1/3 the cost of lipo's per KW/h
    This is where fast moving tech can change options in a short space of time. To say " its not really about the cost" is easy for the person not footing the bill. Batteries come at a cost to the enviroment too, and given the short life cycle of some of them, it would not be considered practical on cost or enviromental impact, both meaningless to some people of course, we all have a choice.

  9. #79
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    Default Re: Heather and electric propulsion

    Quote Originally Posted by Tom Lathrop View Post
    These proposals always draw lots of reservation from the forum. Some call responses negativity but almost all previous experience calls them realistic. Count me among those who like to be more optimistic but past observation forces a large dose of pessimism....

    After spending many years of expert time and money, there are now electric airplanes that can take off and fly with humans aboard but calling them practical looks to still be out in the future.
    There are a lot of people who think that electric power is some kind of magic that is capable of performing all kinds of feats beyond what the cold, hard numbers will support. But John A, who's done the design for converting Heather to electric power, has experience with electric boats and knows what he's doing. I don't know him as well as I know his wife, but he seems to be a real technical nerd. A Good Thing for a project like this.

    Heather is a small boat, for small adventures (don't take her to Tierra del Fuego, Howard! ). Electric propulsion should work just fine in her, with sails and a backup genset, just in case.

    Electric boats are already practical, and have been for a long time. Not for everything -- they aren't practical for towing waterskiers or long passages under power -- but for kind of boating a lot of us here like they're not only practical, they're quite nice. My favorite boat in the Coot fleet is a 15' electric launch. It's roomy, comfortable and, nicest of all, quiet. A great boat for taking a boatload of Coots out for a BS session. Joe has never had a decent set of batteries, but he's managed to have plenty of small adventures on the water without running out of juice.

    The electric cruising boat, Dan Pence's Ginger, that Graybeal mentioned earlier is another example of a practical electric boat. With her first batteries, a bilge full of 6 volt golf cart batteries, she had enough range to cruise the San Juan Islands. They'd go someplace nice and remote, say Sucia Island, and stay there a day or two. Then they'd go someplace with a marina for a night. The wife would appreciate a hot shower and Ginger would get charged up. Then off to someplace else remote the next day. repeat as necessary... A few years ago Ginger got some lithium-ion batteries from a defunct electric car company, and a bunch of lead ballast to bring her back down to her lines. Dan says the range is probably about the same, but there's more room in the cabin, and the lithium batteries will last a lot longer than lead-acid batteries. I heard that Ginger was down cruising the lower Columbia a few weeks ago. The last time I saw her was during this year's Pocket Yacht Palooza Crooza. The photo below was taken on the upper Yaquina River near Elk City after the Toledo Wooden Boat Show last year.
    Attached Images Attached Images
    Last edited by John Kohnen; 11-18-2018 at 05:12 AM.

  10. #80
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    Default Re: Heather and electric propulsion

    Quote Originally Posted by skaraborgcraft View Post
    I do not profess to be any kind of expert, but i did run through a cost conversion for someone who was intending to go all electric. Cut the long story short, electric only was not 100% reliable enough for this persons needs, given open tidal waters to deal with....
    Not reliable? Electric power is very reliable. It's really pretty simple at its heart, and with a little planning in construction the fancy bits can be bypassed in a pinch.

    If there are tidal currents it just makes less work for the motor. Low-power boats, whether they uses sails, paddle, oars, small IC motors, or electric motors just need to be patient and don't try to buck the tide.

    One of the Coots has an electric mini-tug. A real nice boat, but S-L-O-W. It only goes about 4 knots -- no matter which way the tide is going. For cruising he's got a gas outboard to extend his range. A couple of times he's got into some nasty weather in the Salish sea, and had trouble keeping the boat heading into the wind and sea. Turning on the electric motor, with it's big, slow propeller gave him the authority to face up to the elements. Electric motors have lots of torque, like a steamboat.


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    Default Re: Heather and electric propulsion

    Quote Originally Posted by John Kohnen View Post
    Not reliable? Electric power is very reliable. It's really pretty simple at its heart, and with a little planning in construction the fancy bits can be bypassed in a pinch.

    If there are tidal currents it just makes less work for the motor,. and don't try to buck the tide.
    And this is exactly why it suits some peoples needs and not others. Making it "reliable" in the sense he could get from A to B, AND have to deal with a counter current on the way is why it didnt work for him. Of course, he could have added a much larger battery bank to allow for it, but i will let you work out how that spiral pans out, suffice to say, it did not work for the boat he had, that he wished to convert.
    Sometimes weather forecasts are wrong, our ground speed is slower than expected and maybe the place we are headed for is the only secure place to be and only accesable during a certain tide cycle, depends on your cruising grounds, but it might not be possible to carry batteries to extend another 50% duration, where an extra 10l of diesel would do the same. Being forced to disharge a battery bank in order to make a landfall just shortens the life of the batteries even further, though some of the newest car cells do not seem to suffer the same way some others do.
    Im all for it, but it wouldnt even work for my weekend use, as it would force me into marinas for recharging, or running a generator while anchored in a peacefull cove......which then wont be so peacefull.

  12. #82
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    Default Re: Heather and electric propulsion

    Little did I know a simple posting looking for insight and advice would generate such a rich conversation. I figured I might read a handful of advice responses and that would be that.

    It seems considering electric conversion is a bit akin to poking a hornets nest, very cool, a nice way to have the opportunity to get a true picture. As I said in my original post I have no chops for electric propulsion.

    I will take possession of Heather in late March/April so I have time to consider Marty's advice/direction and the electric components that come with the boat as well as all the insight/opinion and advice in this thread. Again I appreciate all of it.

    I have been aboard Heather only once just over a year ago although have been aware of her for several years. I get the boat and most important of all I get how to do her the justice she deserves.

    This justice means no radical steps will be taken as I apply a little lipstick and rouge given she has been lovingly housed for going on 13 years. In fact I have no plans to even change her home port only her paint, varnish, adding full cockpit tent and a refresh of cushions below deck and of course consideration of how I "might" power her.

    Given all the rich content postings here it should be remembered that Heather is only 16 feet long and she is a slippery shape under water.

    I am taking ownership of a boat without a power plant as Marty removed it and that's that.
    This is not a detriment to my thinking in any manner given that I have a crazy bent for the sanctity, purity, peace and skill honing penchant of sail and oar.

    However, I do understand Heather's origins and design reflection of Scandinavian lineage. I respect her designer/builder Tim Nolan and his creation of a superb one of a kind micro sailing, err sailing/motor yacht. So I am open minded yet thinking of powering her as Marty had planned. Marty is a friend who knows what he is doing and so I am following the same path for now but this is open to change as he like me is admittedly no expert in the field of electric propulsion.

    I am sure I will come up with a good solution from the array of options, engineless, hybrid electric options and even a new small diesel.

    I am an avowed engineless sailor with a dent in my engineless armor named Blueberry. I am the fortunate owner of Blueberry and she has a clever small diesel, which I considered a bit of a drawback when I acquired her ten years ago. On first launch into the Connecticut River I commissioned and fired up that diesel before I sailed her down east from Connecticut to Maine. I have to say I loved having that little Vetus on board in spite of the smell and noise. I have sailed aboard many boats with engines so having one was no revelation, yet I still prefer engineless and plan my expectations and routing accordingly.

    In closing I am copying these posts and taking all of them in as good science and strong opinion. In the end I look forward to sharing the path I choose and the joy of seeing a venerable little pocket yacht back on the water as a sight for all to enjoy. Heather may not be for every taste but for me she closes a very long search as she fills a final spot in my quiver of small boats (put them all nose to tail and I own one very large yacht). A curious shift has happened because of Heather, my always searching, roving "have to find just the right boat" eye has slowed to a crawl because of her..........................I'm worried;-)
    13558965_10153920916905000_5745763617005940267_o.jpg
    Ode to her previous noise maker. Nice empty space for?
    13567261_10153930440360000_2855409134763390311_n.jpg
    43672087_759206714430844_5472305620965130240_n.jpg
    A nod to her roots.
    0-4.jpeg
    Me thinks a classic.
    13516187_10153920897685000_4491836175997627972_n.jpg
    Just two years ago I would have never imagined I would have chosen such a boat.

  13. #83
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    Default Re: Heather and electric propulsion

    Have not studied electric power but have read about it a bit. A few thoughts to consider:
    Diesel or electric generator to electric propulsion is less efficient than fuel engine directly to propeller.

    Battery as only source of power has limited range. High capacity batteries have high cost.

    Solar requires a large, expensive collector array to provide enough capacity to power directly or replace charge quickly.

    Fuel for generator can have issues, diesel preferred over gasoline because of fire hazard.

    Ideal electric system would weigh the same as the former engine and use light weight, high capacity batteries salvaged from an electric vehicle as long as the limited range was well within the required usage.

  14. #84
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    Default Re: Heather and electric propulsion

    Howard, congratulations on your purchase. This is a very fascinating boat.

    You might be interested in what I have done so far on my boat.

    http://www.willmarsh3.net/el/aps/elver_aps1.htm

    This will get the boat out of the marina and out of a pickle. I have not tested the range yet but I estimate it to be around 20 miles or so which will get me back from any day trip.

    My total outlay for this was around $3000 or so. Frankly I think LiFePO4 batteries are a much better choice.

    Sailing UMA also uses LiFePO4.

    Will

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    Default Re: Heather and electric propulsion

    There is the possibility that a leg with a large prop, could be dropped through a well sited in the spot where the diesel motor had been located.
    This would allow the genset to run mainly for propulsion and make power regeneration a possibllity.
    Having the bilge keels, makes this feasible......if the drastic mods can be justified.
    Still cannot see where the solar panels are going to be placed.

  16. #86
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    Default Re: Heather and electric propulsion

    oohhh...re generation through the prop..had not considered that .

  17. #87
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    Default Re: Heather and electric propulsion

    You need the right kind of motor to allow regeneration, and a suitable prop......compromises.

  18. #88
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    Default Re: Heather and electric propulsion

    Quote Originally Posted by Howard Rice View Post
    Little did I know a simple posting looking for insight and advice would generate such a rich conversation. I figured I might read a handful of advice responses and that would be that....

    I am sure I will come up with a good solution from the array of options, engineless, hybrid electric options and even a new small diesel....
    Talk to some people with actual electric boat experience before you make your decision about what to put into Heather, Howard. I can put you in touch with some, if you like. I've just ridden in them. You ought to take some electric boat rides too. They're really quite NICE, and that's worth a lot.

    Myles Twete is another experienced Portland electric boat owner. He and Dan Pence shared those lithium-ion batteries one or the other of them got from the defunct electric car company.




  19. #89
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    Default Re: Heather and electric propulsion

    Quote Originally Posted by wizbang 13 View Post
    oohhh...re generation through the prop..had not considered that .
    I have not tried to do any calculation, but I think regeneration probably won't work. You need excess energy, which means quite a lot of energy. This wee thing will be operating with minimal energy, and the drag induced by trying to regenerate more power, will probably need most of the energy you are already using just to keep going.

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    Default Re: Heather and electric propulsion

    Quote Originally Posted by gilberj View Post
    I have not tried to do any calculation, but I think regeneration probably won't work. You need excess energy, which means quite a lot of energy. This wee thing will be operating with minimal energy, and the drag induced by trying to regenerate more power, will probably need most of the energy you are already using just to keep going.
    I might have mis-understood, but i think he might have talking about using the prop as a spinner to turn the motor acting as an alternator, while under sail, its a good option.

  21. #91
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    Default Re: Heather and electric propulsion

    When I get going fast under sail my prop starts spinning. Just out of curiosity I once put my hand on the shaft. I did this carefully because I did not know what force it would take to stop it. But I was able to stop it quickly with my bare hand. That leads me to believe that there isn't much energy to be had from a windmilling prop. Or that a specially designed prop is needed to turn a generator.
    Will

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    Default Re: Heather and electric propulsion

    I think trying to generate electricity from that spinning prop would be counterproductive. Wouldn't it add drag and slow the boat down about equal to what it would generate?

  23. #93
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    Default Re: Heather and electric propulsion

    Quote Originally Posted by Howard Rice View Post
    13558965_10153920916905000_5745763617005940267_o.jpg
    Ode to her previous noise maker. Nice empty space for?
    You could fit four of those little turbines in there. With a powerful motor, maybe she'd plane

    Personally, because I'm lazy, I'd probably go for a really old single-cylinder diesel. Ker-chunk, ker-chunk, ker-chunk ... or even a Hicks, but that's gasoline. It wouldnt be quiet like electric but would definitely be in character for the boat. And not unpleasant.

    Saab one-cylinder ?

  24. #94
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    Default Re: Heather and electric propulsion

    Howard, I opened this thread and the first picture of Heather, my comment was that is a nice 25' lifeboat conversion.
    Then a few posts later I learnt it was only a 16 footer - WOW!
    I know nothing about electric conversions so will say nothing.
    But the guy who designed and built Heather must have had a few naysayers at the shed door saying it could not be done.
    So give the elctric conversion a good crack (the sound of willow on cricket ball) and see how it goes - someone will succeed with a market leading solution for electric drive and we will be all doing it.
    And that picture of the boat in a breeze looks great.
    I have now worked out how you get into the wheelhouse from the picture in post #82......
    Keep us posted with developments.

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    Default Re: Heather and electric propulsion

    Wow, you'd think that using a free wheeling prop to generate power was a bold new idea. Cruisers have been doing it forever. In most cases the prop is there already, creating drag. Many cruisers have fitted a V belt to their shaft and run an alternator, or back in the day, a generator, from it. A spinning prop actually creates more drag than a locked one though.

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    Default Re: Heather and electric propulsion

    Quote Originally Posted by Oldad View Post
    I think trying to generate electricity from that spinning prop would be counterproductive. Wouldn't it add drag and slow the boat down about equal to what it would generate?
    Yes, about as much as a mast ,rigging and sails do on a sailing boat.

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    Default Re: Heather and electric propulsion

    Quote Originally Posted by skaraborgcraft View Post
    I might have mis-understood, but i think he might have talking about using the prop as a spinner to turn the motor acting as an alternator, while under sail, its a good option.
    The prop has to be big enough to create enough torque to turn the generator. This is not free-wheeling, there is drag. The drag, I think would be substantial for this little boat. I could be wrong...as I say I have not done any calculations

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    Default Re: Heather and electric propulsion

    Regeneration works, but the question is if it's usefull for this boat. This depends on many factors. First is propeller size and form because this determines how fast the prop turns at a given speed when braked by the motor. Then comes the question of what current can the motor generate at that speed. Biggest problem for this boat will probably be it's limited hull speed. It is unlikely that any regeneration will happen under 4 knots (even comercial water generators have problems under that speed) and hull speed with a 16 feet waterline is 5.4kn, so basicly regen can only happen in a 1.4 knot range. If the controller has regen capabilities anyway, and a lot if not most controllers for PM motors do, it's a nice to have, but not critical for this instalation. Some controllers have adjustable regeneration levels, from 0 to 100%.
    Generating power this way brakes the boat by the amount generated, it's like running the engine in reverse when sailing, but this is not usally a problem since high power is only generated at high speeds. If his setup generates 100W at 5kn it would be equal to the best commercial watergenerators on the market now. 50W at hull speed would be the most I would expect in a best case scenario. So regen is the same as solar, nice to have, usefull for house loads, but not to be relied on for propulsion.

    The actual thing to pay attention to is the charger. In order to be able to charge while motoring the charger has to be matched to the generator. If the generator outputs 1800W in continuous duty then the charger must have a maximum rating of 1800W also, and be able to sustain this max rating continuously. This would be the ideal charger that operates at 100% efficiency, so in real life the charger will be one with 1600W output. If the charger is bigger it will overload the generator, especially with lithium batteries that can take high amp charging, but also with a big enough lead acid bank in bulk charging.

  29. #99
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    Default Re: Heather and electric propulsion

    This month's Professional Boatbuilder magazine has an analysis of both electric and hybrid boat propulsion. Its by Nigel Calder who is well known and respected for his writing about boat systems.
    Tom L

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    Default Re: Heather and electric propulsion

    Thank you Tom
    Quote Originally Posted by Tom Lathrop View Post
    This month's Professional Boatbuilder magazine has an analysis of both electric and hybrid boat propulsion. Its by Nigel Calder who is well known and respected for his writing about boat systems.

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    Default Re: Heather and electric propulsion

    Quote Originally Posted by Rumars View Post
    Regeneration works, but the question is if it's usefull for this boat. This depends on many factors. First is propeller size and form because this determines how fast the prop turns at a given speed when braked by the motor. Then comes the question of what current can the motor generate at that speed. Biggest problem for this boat will probably be it's limited hull speed. It is unlikely that any regeneration will happen under 4 knots (even comercial water generators have problems under that speed) and hull speed with a 16 feet waterline is 5.4kn, so basicly regen can only happen in a 1.4 knot range. If the controller has regen capabilities anyway, and a lot if not most controllers for PM motors do, it's a nice to have, but not critical for this instalation. Some controllers have adjustable regeneration levels, from 0 to 100%.
    Generating power this way brakes the boat by the amount generated, it's like running the engine in reverse when sailing, but this is not usally a problem since high power is only generated at high speeds. If his setup generates 100W at 5kn it would be equal to the best commercial watergenerators on the market now. 50W at hull speed would be the most I would expect in a best case scenario. So regen is the same as solar, nice to have, usefull for house loads, but not to be relied on for propulsion.

    The actual thing to pay attention to is the charger. In order to be able to charge while motoring the charger has to be matched to the generator. If the generator outputs 1800W in continuous duty then the charger must have a maximum rating of 1800W also, and be able to sustain this max rating continuously. This would be the ideal charger that operates at 100% efficiency, so in real life the charger will be one with 1600W output. If the charger is bigger it will overload the generator, especially with lithium batteries that can take high amp charging, but also with a big enough lead acid bank in bulk charging.
    Dragging a rotating propellor, especially one designed for propulsion creates several times more drag than the same prop when fixed. Raceboats that would carry a higher handicap when fitted with a folding prop have a brake on the shaft to prevent it from rotating for that very reason.

    John Welsford
    An expert is but a beginner with experience.

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    Default Re: Heather and electric propulsion

    Yes, dragging a rotating propellor is usually described as equal to dragging a solid disk of the same diameter.
    The drag spins the prop, and the rpm's increase with speed. In order to generate current the water has to spin the prop with enough force to turn the motors rotor. There is actual energy needed for this, more then the current beeing generated.

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    Default Re: Heather and electric propulsion

    A torquedo pod drive and a very small Honda generator would be perfect for this darling boat. The limitations for it are clear. You want to keep the lines, minimize the foot print and have push button power. This gives you all in a very practical neat solution. The motor install would be over a weekend. Total outlay of cash would be around 6k.

    501E60FB-EEA9-466E-9D93-762397707582.jpg

    I too have looked for an electric propulsion system for my raceboat. It needed to be practical enough to get me in and out of the harbors, to make dead wind estuary runs, being to put the boat into irons and for safety reasons. The pod made sense for it. I was going to pull the trigger but somehow lost interest. I also was planning on carrying a 1000w Honda generator to pair up with the solution beyond minimal batteries. The weight savings would be significant.

    I did saw many practical electric working and pleasure boats in Amsterdam early last spring. Perhaps a fact finding mission is in order...
    Last edited by Ted Hoppe; 11-23-2018 at 10:35 AM.
    King Moonraiser:
    A toy is never truly happy until it is loved by a child.


  34. #104
    Join Date
    Jan 2010
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    Northern Europe
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    9,572

    Default Re: Heather and electric propulsion

    Given how many outboard gearboxes take on a bit of water after a while, i dont fancy having an electric motor under the water ,depending on some O rings to keep it functioning, or am i missing something?

  35. #105
    Join Date
    Nov 2006
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    Default Re: Heather and electric propulsion

    Quote Originally Posted by skaraborgcraft View Post
    Given how many outboard gearboxes take on a bit of water after a while, i dont fancy having an electric motor under the water ,depending on some O rings to keep it functioning, or am i missing something?
    That is some of the trepidation. The O ring failure is one and the aluminum housing corrosion another. Then again if a motor has a 3 year warranty and if one pulls the boat out regularly, the issues are mitigated somewhat. The pods can be removed and replaced pretty easily.

    With new motor installations - one of the biggest headaches is controller placement and functionality. Sure is nice to have a simple to install, robust and small interface. That too is an overlooked aspect to what ever propulsion system is selected and more important on smaller vessels where real estate is more valuable
    King Moonraiser:
    A toy is never truly happy until it is loved by a child.


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