"Current Situation" DIY Efficient Solar/Electric Powered Newport 17 Project

Discussion in 'Boat Design' started by ElectroDanO, Jan 1, 2021.

  1. Dejay
    Joined: Mar 2018
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    Dejay Senior Newbie

    Yeah I don't know about the prices... I've looked on alibaba and there seem to be wholesale prices of 2.5€/kg if you buy 120kg of PMMA sheets. That would be 6€/m² plus shipping and taxes. Maybe it's a racket if you try to buy it here, or maybe prices is the reason we don't see acrylic solar panels.

    And nice rendering! I just replied to your thread.
     
  2. Jeff in Boston
    Joined: Sep 2020
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    Location: Boston

    Jeff in Boston Junior Member

  3. Kayakmarathon
    Joined: Sep 2014
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    Location: NewEngland

    Kayakmarathon Junior Member

    1 HP is about 746 W. A small sailboat like that could be cruised with a 5 HP motor.
    Energy from the sun is 1360 W per square meter. Solar panels are 15 to 20 % efficient, so you would need about 16 square meters of solar panels for a leisurely cruise.
    An electric-sail hybrid would be the best combination. There may be a way to recharge the batteries dragging a prop or paddle-wheel while under sail.
    Electric motors are more efficient with higher voltage, and batteries work better when they are cooler; so several parallel banks of a series of batteries ( 120 V total) will help. A boost type DC-DC converter may be needed.
    The 12 volt trolling motor will not take much higher voltage; so a brushless, DC motor designed for at least 120VDC is needed. See if you can find a 7 to 10 HP motor and retrofit it with an electric motor to the shaft.
    Be sure to give the motor, electric drive stage, and batteries enough vented air to avoid overheating.
    Batteries will last longer if stored at 40 degF and 40% charge. Once a month "charge" them for 5 minutes to replenished what trickled out.
    Don't store a fully charged battery.
     
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  4. ElectroDanO
    Joined: Jul 2019
    Posts: 29
    Likes: 24, Points: 3
    Location: Smyrna TN

    ElectroDanO Current Situation

    Sorry, I've been having too much fun playing with this thing and not updating this thread.:D It was a long winter and I'm beyond happy to be back on the water doing some boat camping and testing out the new upgrades!

    Going LiFePO4 was the best decision ever! Definitely a learning curve starting from scratch, but there's no going back now. I'm 100% sold! There's not much reason for solar with the current setup. I got in a little over five hours of run time, ran the lights for a couple of nights, charged my devices and still had 50% capacity left using only one battery. How cool is that!?!? Oh, and the weight savings. She doesn't lean to one side anymore!;) I decided to move the battery placement to the middle of the boat on the floor just under the hatch. I had to lengthen the cables by about four feet, but it's nice to have quick and easy access and have that weight low and more centered. That being said, is there a center of gravity that I should be aiming for?

    So, how fast is she with less weight and more power? Well, still pretty dang slow. Faster than she was though! The motor is still the MK30 with an 11x6 APC prop and PWM control: 50% throttle=2.1 MPH, 80%=3.2 MPH, 100%=3.9 MPH. I tried more aggressive props but speed went down and of course, current went up. I'll try a little smaller prop soon, but that's probably about all the little 30lb Minn Kota has in her trying to push this 17' boat. Definitely have plenty of room to add a more powerful motor now. Not sure what the plan is yet, but I want to build a brushless setup. Twin drive maybe? Whatever we come up with, it'll be cool looking, more powerful and hopefully not go up in smoke! Give me some ideas...

    In other news, with help from my lovely Mom, we made a screen hatch cover to keep the bugs out and the fresh air flowing. Started with a magnetic screen door from Amazon and cut/re-sewed to fit the hatch. Works great! It's attached with velcro so it's easily removable and no(more) holes were drilled in this cool old boat!
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    Also, she got a new bimini top! Not sure how I feel about the color yet, but I think we can make it work. I did hoist up the old solar panels this week. They need to be upgraded BAD. But, with what little they're putting out, I still came home with almost a full battery. The potential for some really cool stuff is definitely there. Back to work!
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    And a sunrise/sunset from Tennessee. This old boat is obviously a work in progress but she's lake ready anytime! Absolutely love it out there!:cool:
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  5. portacruise
    Joined: Jun 2009
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    Location: USA

    portacruise Senior Member

    "So, how fast is she with less weight and more power? Well, still pretty dang slow. Faster than she was though! The motor is still the MK30 with an 11x6 APC prop and PWM control: 50% throttle=2.1 MPH, 80%=3.2 MPH, 100%=3.9 MPH. I tried more aggressive props but speed went down and of course, current went up. I'll try a little smaller prop soon, but that's probably about all the little 30lb Minn Kota has in her trying to push this 17' boat. Definitely have plenty of room to add a more powerful motor now. Not sure what the plan is yet, but I want to build a brushless setup. Twin drive maybe? Whatever we come up with, it'll be cool looking, more powerful and hopefully not go up in smoke! Give me some ideas..."

    Nope, the MK has more in it! You can easily run the MK at twice the voltage or more, so long as you stay below your present maximum amps and run it so it bypasses the resistors ( at highest speed five) or is wired around the existing pwm. Use a new external pwm that runs at the higher voltage. This is done by changing out the propeller to a less aggressive one, ie. lower pitch and/or smaller diameter. It will take a bit of tinkering with different propellers, but they are low cost, so can be ordered by the handful. Maybe start with a 9 X6 and see where that takes you in terms of amps and boat speed, then hone it up or down to your very best choice. I ran a 12v motor at 24v for many years without any damage whatsoever, even while getting twice the power out of it.
     
  6. ElectroDanO
    Joined: Jul 2019
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    Location: Smyrna TN

    ElectroDanO Current Situation

    Alright, we'll keep hammering on the MK30 for a while longer. I guess I meant, that's probably all she has on 12v...:p

    Next up is something I've wanted to do for a while. Water cooling! This PWM has always gotten pretty warm, even at low loads. Hasn't let me down yet though and I'd like to keep it that way. No resistors here. One of the first things I did was add the PWM and wire it straight to the motor with good 10awg marine wire.

    We'll turn the voltage up some also. I don't really like the idea of using a converter because of the added complication and losses, but this 40 amp model should be fun to play with and a heck of a lot easier than changing the battery setup. Who knows, I might fall in love with the thing. Probably not though... I'll order up a cooling block for it also.

    Haven't studied much on how I'm going to add all of this in and make it pretty. I have some ideas but they could take some time. "Pretty" might have to wait till lake season is over...
    [​IMG]

    Props? Yeah, I went a little prop crazy a while ago. Used props are $1 each at the local hobby shop. That's pretty cheap entertainment right there! :cool: I'm still trying but a stock APC 11x6 has been impossible to beat so far in efficiency and good speed with the current setup. Fun stuff!
    [​IMG]
     
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  7. portacruise
    Joined: Jun 2009
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    portacruise Senior Member

    Thanks for the report!

    So will you be using a dc 12v to dc 24?v up converter, for your source of higher voltage, then? I'm wondering if the up converter and PWM will play well together, since they are both dc pulsing devices. Hopefully the pulses won't interfere with each other, or the up converter has some pulse smoothing circuits in the output.

    Another thing to try on props with the present 12v setup is the wide versions from APC which might give you a little more, like they did for me. But running at double voltage with a properly matched prop was a much more impressive increase in high-performance for my rig...

    It might not be necessary to change your battery setup to get 24v instead of 12v. It might be possible to temporarily jurrie rig two 12v car batteries with jumper cables in series if you can retask or borrow them from some other equipment, at least long enough to test the concept before you invest $. You don't need a new 24v PMW if only want to test maximum performance. You can start with very small/ low pitch props that have very low current draws and run direct w/o PWM while watching max current as you move to more aggressive props.

    Hope this helps.
     
    Last edited: Jul 2, 2021
  8. ElectroDanO
    Joined: Jul 2019
    Posts: 29
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    Location: Smyrna TN

    ElectroDanO Current Situation

    This converter is adjustable so, I should be able to set the voltage and current limit. Well, within reason anyways. I have a buddy that ran this setup and it worked, but wasn't reliable and wound up smoking the motor(MK30). He was running it pretty hard in some fast current. Hopefully I can "sneak up on it", keep an eye on temps and get a little more out of it reliably. I don't know, we'll see...

    I haven't heard about the wide APC props. I'll have to look into those. Thanks!

    I bought 8 Lifepo4 cells and built two 12v packs. I switch them out every trip and baby them like crazy. I could go 24v with the cells I have now. My "40a" PWM will handle up to 48v so, that's not a problem. That being said, my same buddy just built a 48v lithium battery and went to a 101lb MK motor and water cooled PWM. Yeah, he's not having trouble with that fast current or heat anymore. Cool stuff.

    I'm in no hurry, literally. This boat is working perfectly as is.:cool: We'll play with it a little more this summer and do some bigger upgrades when it's not so beautiful out there.:D
     
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  9. ElectroDanO
    Joined: Jul 2019
    Posts: 29
    Likes: 24, Points: 3
    Location: Smyrna TN

    ElectroDanO Current Situation

    Well guys, I learned the hard way(as usual) that you don't just sit down and start working on circuit boards with zero experience... About halfway through botching my PWM, I got a replacement on the way and stumbled across a more robust looking "60a" unit. It was my birthday so, I ordered one of those also.:D

    Here's a before picture of the "40a" PWM next to the "60a" model. What a beast! I'll carry that as backup for now.

    [​IMG]

    I upped my soldering tools, practiced like crazy and came out with a win tonight. Moved the MOSFETs to the bottom side and laid them flat for the cooling block. Hopefully button everything up tomorrow and see how she works!

    [​IMG]
    [​IMG]
     
  10. mitchgrunes
    Joined: Jul 2020
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    Location: Maryland

    mitchgrunes Junior Member

    Beautiful photography, lovely weather.

    What do solar electric boaters do when clouds block the sun?
     
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  11. ElectroDanO
    Joined: Jul 2019
    Posts: 29
    Likes: 24, Points: 3
    Location: Smyrna TN

    ElectroDanO Current Situation

    Sit back and read "Sailing For Dummies"?:p Seriously, it works out pretty good for guys like me that only go out when the weather is decent and can usually start off with a full battery. Not sure what the plan would be in a big boat that takes massive power to move with days of cloud cover. Better have a BIG battery bank!:eek:

    Water cooled PWM is ready for a lake test. It's not super pretty yet but the cool factor is still off the charts!:cool: Man, this little pump flows really well and is only costing me 6w! I think my old fan pulled 4w. Cool!

     
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  12. portacruise
    Joined: Jun 2009
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    Location: USA

    portacruise Senior Member

    "What do solar electric boaters do when clouds block the sun?"

    Same thing that sailboat users do in conditions of Dead Calm?

    Maybe a kite could be used if solar is out and vice versa with solar panels.

    There's also wave power which could be brought into the mix?
     
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  13. portacruise
    Joined: Jun 2009
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    Location: USA

    portacruise Senior Member

    Dummy me did not realize that heat was that much of an issue with PMW. I thought most of the heat is generated at high current draws, and that there was a pass with high current draw, at least with some designs? Or perhaps someone might go to much higher current ratings (above fused motor stall current) for the PMW, to keep the heat stress low?
     
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