Help in the right direction with basic small scale diesel electric

Discussion in 'Hybrid' started by saltnz, Dec 6, 2016.

  1. saltnz
    Joined: Feb 2010
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    Location: New Zealand

    saltnz Junior Member

    i was wondering if someone could point to some good reading for small scale diesel electric hybrid.
    I have a 22ft sailboat and 6hp is more than enough
    Is is way toooooooooooooooo much info out there for big and sophisticated stuff and all electric. I am not interested in saving the planet or maximum efficiency I just hate ouftboards.
    I really like the look of the torqueedo 24v outboard, but could not make an all electric and limited range work.
    Small boat so don't want anything big nor interested in AC, just something to run top to up batteries or supplement when steaming. I have a cavity that a farymann 18w would fit into nicely. I thought fitting a 24v 75A DC alternator a regulator battires and I am off. However I am having a hard time finding information that is relevant to such a small solution.
    Any help much appreciated
     
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    You can simply hook up the Torqueedo to the batteries and charge the batteries with the generator you propose to build. It will be inefficient, heavier and more expensive than using the farymann as an inboard propulsion though. However, if you don't care, the solution is simple.
     
  3. saltnz
    Joined: Feb 2010
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    saltnz Junior Member

    I have considered sterngear in the past, but it is a trailer boat and I like to cruise in a place where you dry up in lagoons. And my hatred of outboards is fierce.
    I am not concerned about efficiency it is just back when batteries low, plus 7hp diesel ...........pfffft
    Expense of torqueedo and the weight of batteries and farymann is a concern. A yanmar is just too heavy I think.
    I have found a cheap farymann in a AC generator on a local eBay-like site so maybe a bit more affordable. I am good with engines and stuff, but would have thought there is either plenty of previous threads or some howto guide for similar projects so I could look more into the feasibility.
     
  4. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    You have prescribed some electro-convulsive therapy to cure this ? :D
    Pretty hard not to find something suitable for most small craft in today's expanded selection of outboards.
     
  5. CDK
    Joined: Aug 2007
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    CDK retired engineer

    Here is a picture of a very small emergency generator I made several years ago. The brand new engine was on Ebay for approx. $120, the alternator for half that price.
    You could use something similar to charge the 24V battery for your Torquedo or whatever electric motor you intend to use.
     

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  6. rwatson
    Joined: Aug 2007
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    Location: Tasmania,Australia

    rwatson Senior Member

    There is a good article on Diesel/Electric "Hybrid" systems in the latest "Professional Boatbuilder", that has some usefull information.

    But, as far as "saving the planet" with a 7 hp electric motor, I think you are somewhat optimistic. The extra carbon emitted to produce the metals and plastics in your batteries, as well as their transport to your location, and future recycling effort, make a small outboard look positively green ( Interesting link below ) , even with the future fuel bill.

    If you re-charge your batteries with a petrol generator it only lowers your "green rating" further, as the loss of efficiency charging the batteries from the petrol generator, and the fact you are converting fuel to electricity anyway, would be more Carbon efficient if you just connected the generator to the propellor.

    If you use coal-fired mains power, to charge the batteries, you still incur a big future "carbon bill"

    Then, multiply the extra power you need to drive the boat with the extra battery weight, not to mention the extra towing weight, and the whole exercise becomes just a non-result.

    Finally, if you hate a fairly quiet outboard with its exhaust muffled underwater, you are really going to go mad with an onboard petrol generator.

    Dont get me wrong, I am all for reducing Carbon emissions, but a small electric system aint going to do it.






    references .............
    "One very simple rule of thumb is that the average manufactured good, containing an average amount of recycled material, will have a carbon footprint of around 2. That is, for every kilogram of an item’s weight, 2 kilograms of CO2 were emitted producing it. This is only an approximation, but is surprisingly accurate for a wide range of manufactured goods.

    However, for one of the most common type of new batteries, lithium-ion, the carbon footprint may be much higher. One study found the carbon footprint to be 173kg per kilowatt-hour of storage. For the battery pack they looked at, 18kg of CO2 were emitted per kilogram of weight."
    https://www.solarquotes.com.au/blog/does-battery-storage-help-or-hurt-the-environment/
     
  7. saltnz
    Joined: Feb 2010
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    saltnz Junior Member

    Hi thanks for everyone's input.
    Just to clarify I am not interested in saving the planet or how efficient it is. People may scorn at my attitude, but that is going off topic. I am talking a small engine for aux propulsion only.
    The bulk and weight of an outboard is my major problem. I have an outboard well and it makes solo sailing extremely difficult. I did try using a different system suggested by another user which makes handling motor better, but now it is getting more in the way and cluttering the cockpit. I have been rebuilding a 1970s 2 stroke evinrude cos it is the lightest and smallest option.
    I have tried a newer Yamaha but it was too big and had a stupid tiller.......I could keep going, but you have to trust me when I say I hate outboards
    CDK what you have setup is exactly what I was thinking about. I am just wanting to find more information about all the components involved and consideration to make such as amperage of alternator and load on engine, difference in regulators etc.

    Rwatson I will check out that professional boatbuilder that is exactly the kind of thing I am looking for
     
  8. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    A 3.5HP outboard will have more thrust than the Torqueedo. It weighs about 18 kg. The Torqueedo is 14kg. There is no significant difference.
     

  9. rwatson
    Joined: Aug 2007
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    Location: Tasmania,Australia

    rwatson Senior Member

    Hahahaha I TOTALLY missed the NOT in your original post :)

    Sorry about that. I was in a very noisy environment and I got all excited after just having researched the topic. Sincere apologies.

    Good luck with it all :)
     
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