Operating Cost of 70' Steel Fishing Vessel?

Discussion in 'Powerboats' started by CatBuilder, Sep 15, 2010.

  1. CatBuilder

    CatBuilder Previous Member

    All good advice. I do need to add one thing into the equation:

    We will spend nearly 100% time at anchor or on a "mooring", which is a permanent anchor built into the harbor in the States with no power.

    We will need to be self sufficient...

    This changes the thoughts on propane, I think. See the following freezer:


    Or... possibly just a very large battery bank that our "non-guest" systems can use while between charters.

    It is actually a very difficult question because we will need power for all the luxuries of home while on charter, but when not on charter, we will still be off grid and will want to minimize expenses as much as possible.

    I will need off-grid power I can scale.
  2. CatBuilder

    CatBuilder Previous Member

    Hi Richard,

    1) I think you are potentially correct, from a financial standpoint. It would be smartest to complete the job and sell her as a new boat. A loan would be a great way to do this. I do not have a source for such a loan, though. Also, I do not have it in my (physically) to build a 45' catamaran, then restore/convert a 70 fishing vessel back to back. Those are two incredibly difficult project, involving a total of 5 years full time labor (without getting paid).

    2) No, it is unfortunately, but this method of construction cannot be changed mid-stream. It is very unique. I cannot, for example go from cylinder molding, to KSS (Kelsall) or over to cold molding during this build. The entire design is dependent on the build method.

    Thanks for the thoughts though.

    What I *am* about to be putting on the market though are the plans for a Kurt Hughes 45' Cruising cat, along with a FREE building space for 2 years in FL, 3 good hulls and the mold for the Kurt Hughes. All of that is worth a couple bucks to someone who wants to build a Kurt Hughes. However, there are probably 1 or 2 people in the whole world who are interested in building one. Probably zero of them live in FL.
  3. apex1

    apex1 Guest

    You have a massive problem Mate!

    Always off grid costs.

    The cheapest solution (it is a joke to use that term I know), is a massive battery bank for the hotel load with DC generation. Part of the latter provided by high power alternators coupled to the main engine. You then need a bank of inverter / charger / battery and genny managing devices like the Victron Multi plus and quattro.

    Such setup is by far the cheapest way of power production and storage for inconstant hotel loads, but the investment is hughe. Doesn´t matter on my multi mio $$ yachts but here?

  4. CatBuilder

    CatBuilder Previous Member

    Ahhhh.... thank you for the confirmation. Again, your conclusion is one I am coming up with after spending the afternoon thinking about this one and looking at some prices.

    I will come up with a similar system to what you describe. I was thinking I might do the reverse of what you are saying though:

    A large battery bank for the smaller load and a generator (with operating cost passed on to passengers) for the larger hotel load.

    This way, the battery bank for the small load could be charged up as the hotel load was going. When there are no guests and no hotel load, the battery bank could keep our smaller loads running for quite some time.

    Many of the boats I'm looking at come with 20kW generators installed already. One of them even has two!!

    Lastly, with that "reverse" setup, we would be able to run the large 20kW generator only once in a great while to charge the big bank when no guests are aboard, mostly living off the battery bank for several days at a time. (I still must do the math here)

  5. apex1

    apex1 Guest

    Well, worth a thought that "reverse" setup.

    One of the main concerns besides "kW throughput" cost, is the charge characterictics of the different battery types.
  6. Stephen Ditmore
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    Stephen Ditmore Senior Member

    1 person likes this.
  7. apex1

    apex1 Guest

    You may find this helpful:


    Attached Files:

  8. Bglad
    Joined: May 2010
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    Location: Jacksonville, Florida

    Bglad Senior Member

    In the US probably other areas of the world:
    One more push towards batteries versus propane is that any propane appliance you were to consider putting aboard such as water heaters, refrigerators, or regular room heaters would be considered unattended by ABYC and NFPA and would require room sealed combustion chambers (inlet and combustion gases). Most I have seen are not configured that way. Cooking appliances are another matter but have their own set of rules which are far easier to meet. This matters for your safety and may affect the insurability of your vessel.
  9. CatBuilder

    CatBuilder Previous Member

    So, then... does that mean Dicksinson is going out of business?

    These heaters aren't frowned upon by anyone...


    I know of many trawlers with 3 way DC/AC/Propane refrigeration systems in them.

    I will review the ABYC book/manual/bible and see what it says about this. Are you simply referring to supplying combustion air to the combustion process and venting the exhaust outside? If so, that is something that's necessary on gas adsorbtion refrigerator for proper functioning anyway. You can't install them without a proper "chimney" behind them or a fan blowing the gasses by. The refrigerators itself won't work if you don't have that airflow. I know about these things... I've installed 3 of these so far in life. :)

    However, I am leaning toward using PTACs for the heating and cooling of the guest quarters, for simplicity's sake. Can't have guests fussing with propane heaters! ha ha :) This might push everything toward the electric solution anyway...

    I'm going to have to do the numbers and consult with the ABYC bible. Thanks for the reminder to stick to code.

    Good reminder.
  10. Bglad
    Joined: May 2010
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    Bglad Senior Member

    Here is the reference.

    Under ABYC A-26.4 Definitions: Room Sealed Combustion system - a combustion system in which incoming air, the combustion chamber, and the outgoing products of combustion are sealed from the boat interior.

    Bill G.
  11. WestVanHan
    Joined: Aug 2009
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    Location: Vancouver

    WestVanHan Not a Senior Member


    Considered an engine driven/cold plate reefer unit?
    If you're going to be charging batteries anyways,why not have an electrically clutched unit off your gen set?
    And have a combo unit-12 volts and cold plate.At docks,plug in to run refrig....at anchor charge the plates and they're good for a few days.
    Or if you have lots in the battery bank,turn on the 12 Volt to cool it out a few more days.
    If it's there already...great..but anyone I've talked to who changes to Adler Barber 12volt systems is always very happy.

    Also maybe run a heat exchanger off the gen set for the hot water tanks and to heat the boat when necessary...just a waste to pump all that nice hot water into the ocean.

    I built my own hybrid system like this a few years ago...

    FWIW I have a nice stainless sideburner propane BBQ,and very rarely cook inside. Most of the time am burning something up with veggies/potatos on the Q,and anything else on the burner.

    My preference is DC boat,with an inverter for any AC loads..which if done a certain way may come down to just the washer/dryer and entertainment .
  12. srimes
    Joined: Sep 2008
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    srimes Senior Member

    what kinda of time spans are you figuring between charters, and at what estimated energy usage?

    I would be careful not to put in too large of a battery bank. They leak energy, in addition to their high purchase cost. While it may be more pleasant to have a larger bank than what is optimal (cost-wise), from a financial standpoint it may be safer to undersize vs. oversize the bank.

    If you're looking at longer times at mooring a wind turbine might do the trick.
  13. CatBuilder

    CatBuilder Previous Member

    Oh, yeah... that's just saying you need to pipe in combustion air and and seal it off from the interior. This if for CO purposes.

    I agree with the definition/spec. The gas powered fridge is sealed combustion, if installed to the manufacturer's specs. As to the hot water heaters and other types of heaters, it depends on which you buy. As it happens, the Dickinson in my picture above is sealed combustion.

    Another word for that they use on land is "direct vented" propane heaters.
  14. CatBuilder

    CatBuilder Previous Member

    Nice suggestions. Thanks. As soon as I figure out the 3 modes of operation (full with guests, a few guests, no guests), I can see how some of those ideas would apply.

    I hadn't been thinking of mechanical systems, so thanks for adding that into the mix.

    We will be permanently away from the dock, so there is no "dock." All systems must be self sufficient. The only dock we will touch is a fuel dock from time to time.

    I can't use an Alder Barbour system for this application. This is a commercial operation with a menu. There needs to be a lot of frozen items and a large, easy to use refrigerator for the cook (wife).

    Fantastic idea on the heat exchanger on the large genset! That would definitely help cut some of the energy requirements.

    Yes, during our charters I do grill about twice a week. I'll be putting a full size Home Depot home grill on there because I can't use "yachty" stuff anymore... too many people to feed.

    Good thoughts.... I'll come at it from every angle to see what seems to make sense. Thanks!


  15. CatBuilder

    CatBuilder Previous Member

    A wind turbine? I'd be interested in hearing more about what you know about this working in this kind of situation.

    I had a wind turbine (Air-x) on my last catamaran. It did nothing for us. It produced maybe 5% of all power used on the tiny, energy efficient boat. The rest came from solar. Again, we never touched a dock. Do you know of some very large wind turbines or something? Our old one didn't put anything out unless you were practically in a gale. What brand and model are you thinking of?

    Time spans will hopefully be charter guests full time for 4 months, then 2 months off or moving the boat, then 4 months full time again, then 2 months to move the boat again (and rest).

    Typically, when I install a battery bank, I "right size" it. I take the maximum amp hours expected to be used in a day, then double that figure and install a bank of that size. I don't usually under or over size it. This sizing technique applies to wet cell batteries, of course.
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