Owning a 40 foot trawler with no generator?

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moparharn

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Is it comfortably possible to own a 40 foot single diesel trawler and do a few two week cruises with it along with day and weekend use (Seasonal Great Lakes) and not have a generator onboard? Two 12-16k but a/c units, refrigerator freezer combo, navigation, running lights, fresh water pump, toilet, and microwave. Rather than buying a generator, buy solar panels, large battery bank, inverter, and bigger engine generator? Has the technology evolved to do this without much difficulty ? I am starting with a clean slate and trying to decide which way I would go if I purchase. Boat is wide open at the moment with limited wiring already installed. Needs full 110 wiring and panel installed still. Is the answer pretty simple? As in- no, not a good idea if starting with a clean slate, or yes- only if starting with a clean slate. Thanks for any thoughts you might share. Electrical is by far my weak suit, and I am hoping to control cost. Cost is the sole motivation behind this question, but a non-starter if not even possible.
 
The answer is probably yes - you can forego the generator, but a lot is personal decision. But it depends on a lot. LFP, hi-ourput alternators and Solar are great and can do a lot. But they have their limits. Without more info on your expectations and boat, it's tough to say much useful.

Peter
 
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I actually removed a working but ancient generator from my boat and replaced it with solar panels. You need to work out the energy budget for your boat. In my case I manage well with:
- 6 panels x 330 W for a total nominal power of close to 2 kW
- replaced electric stove with propane and removed three non-working AC units
- 900 A-h @12V of lead-acid batteries
- cruise only in the summer
- 2x100 A alternators
 
We spent years with no onboard generator. However we did have a honda 2K on the swim platform.

The honda could handle almost everything, just not at the same time. I would heat the water first, then when hot, shut the water heater off and run the battery charger.

It could run the electric stove, microwave, toaster oven, coffee maker. But again, not all at the same time. It could run the smaller 5-6K BTU AC/heater in master, but not the 12-15K in the salon.

We cruised, detached from shorepower for 11 weeks and only ran off of that Honda 2K and were fine.

Not3 that we are in New England, so when anchored, you RARELY feel the need for AC and fans can typically cover those couple of nights when it's hot and humid. It's much cooler out on a mooring or in the anchorage than in the marina.
 
I would think the high load items as in ac,hot water and microwave and cooking loads would have to be looked at. I would definitely have some form of emergency power as previously posted.
 
The only thing that really counts is the A/C units -- everything else is small. While a microwave draws a thousand watts, it's not on for long. Hot water can take heat from the main engine. I assume your stove is propane. You're in Detroit, so presumably cruising nearby, not in places where you will see 90+ for long periods.


A single 16kBTU A/C unit will draw around 1200 watts, so two will draw 2500 watts. That's within the capacity of the largest 12V inverters. A big alternator on the main engine will put out close to that. Solar can help -- good solar will produce around 16 watts per square foot, so to carry the load entirely on solar would require 150 square feet of solar, which is a lot for most boats.


So,if you plan to be moving most of every day, then you can stay ahead of it during the day with the main engine, but you mustn't run the main engine with just the alternator as a load. If you pull into a marina every night, then you can certainly stay ahead of it with shore power and big enough batteries.


But, if you plan to spend a lot of time on anchor, it would be best take the suggestion above and pack a small Honda gas generator to keep things going.


Jim
 
A 40 footer without a generator is most likely designed to operate without one. I.E. propane stove instead of electric. Hot water from engine exchanger. Ice box instead of 110v fridge. Natural hair drying and no laundry.

But, If you want the home creature comforts after two days on battery/inverter then you need a generator.
 
I agree with the above posts. Pretty much forget about using the AC units unless you are tied up to a dock. Ditto goes for heaters, unless they are using coolant from the engines while underway. The addition of a small generator like the Honda EU2000 or 2200 can supplement your electricity IF you come up with plans to mitigate storage of gasoline, potential CO poisoning, and other issues.

A 40 footer doesn't have a lot of real estate to put solar on.
LiFePO4 batteries would help a LOT!
Best of luck in whatever you decide!:dance:
 
It can easily be done, except for the AC. If you want hot water and cabin heat, that can be supplied with diesel. All the other electrical loads can be supplied with a decent alternator and reasonable solar. I've put about 10 hours on my genset in 5 seasons (live aboard for months at a time), mostly to warm it up to change the oil once a year. Solar, lithium, and an alternator are far cheaper than a genset install.
 
The only thing not on an inverter is the AC. We converted everything to DC. House runs off an 8D. We have a generator, but could live without it.
 
Agree it can be done initially by going marina to marina. Anchoring out is different.
Propane stove instead of electric.
Efficient refrigerator would be great but the average 12/120 volt refrigerator found on trawlers draws about 5 amps DC whenever it’s running. It will run a lot more in summer with a warm cabin.
Engine heating coil for the water heater.
A standard alternator on a single engine diesel is only maybe 60 amps when cold. Half that when cruising. You can bump up to 100 amp alternator with a single v-belt and wiring upgrade fairly easily. That will recharge the batteries for one night IF setup properly.
OR
A big cooler,, bags of ice and propane stove like sailboats have done for years
 
I’m contemplating removing the Lima generator from my single engine Willard. The generator is driven by a 50 hp Perkins 4108 originally sized to power an AC get home engine which was removed by a PO. To do this I would need to add battery capacity, swap out my 160 amp house alternator for something larger, add 300 to 900 watts of additional solar capacity and convert my old electric stove to an induction unit. For A/C at night even more batteries and one of the smaller DC powered A/C units would be needed. This would all probably be more expensive and more complicated than swapping out the 4108 for a smaller and quieter generator.
 
I just put Solar on my boat, albeit smaller, and we have a 3000 KW Portable Generator, plan on multiple day trips out to Catalina Island. That said, if I had room for a permanent generator, I'd have one! Solar probably cut's the need for a Generator by 60% but when you want the creature comforts, it's nice to have!
 
I’m in a 40 foot trawler, have a genset, but almost never use it. I have a pretty big house bank at 1125 amp hours, have about 750 watts of solar on the pilothouse roof and a 225 amp balmar alternator.
We leave the inverter going 24/7 for creature comforts, no air conditioning, hydronic heat, propane stove. The solar can make up our daily needs in summertime, with the exception of hot water. We make hot water when under way. If I need hot water after being at anchor for a couple of days, then I might fire up the genset, or, if I’m feeling flush on the battery reserve, use the inverter.
I could easily go without the generator, but since it came with the boat, I use it about 5 hours a season. (If that)
 
You don't need AC in the Great Lakes except Detroit and south in Lake Erie. Even there AC is not totally necessary. AC is necessary in the Southern US. Heat is more useful north of Port Huron.
 
Like others have stated it would be a good idea to make an Excel sheet and write down all the consumers you have onboard. Don't forget the items like plotters, gps, radio etc, all together they can still have quite a draw.
Once you have identified them all then figure out what their max draw is and how many hours or minutes they will be working. In the end you will have a good overview of the total amps you will use on a daily basis.
From there you can start planning the usage schedule, after all not all equipment has to run at the same time. Figure out what you can do during day time and what can only run at night. This is important if you want to figure out how many solar panels you need.
After that figure out what the usable sun is in the area where you are sailing. Based on that you will know how many amps one panel can supply on average. Since you know how many amps you need you also know how many panels you need. And with that you will also know how many Ah you will need in batteries.
I went for triple the daily consumption in battery capacity, which means I can have 3 days without any solar output and still be able to run everything in normal mode. In reality you will most likely start up the engines if the weather has been bad for a few days, in order to get to some better weather and that will charge the batteries again.

If you would take this approach you would not need a generator, but it comes at a price. We basically live on our boat for 8 to 9 months, so not using a generator saves us about 12.000 - 13.000 euro a year. If you only use your boat short periods of time you may actually be cheaper off with a 5 of 6 Kva Onan generator.
 
One thing to consider is that most boat fires initiate from the battery storage energy side. You have a stored energy that when things go wrong, sometimes you can't turn off. I'm not saying a fuel tank of diesel doesn't have the same potential, but having an additional large bank of energy is something to consider. Cut-off switches can weld themselves closed, batteries can overheat, too many amps through a conduit, switch, relay etc can start things down the wrong path. Obviously, there are lots of systems out there that work just fine, but most aren't cheap. Also if you are looking at resale, I doubt you would find a buyer that would refuse because it has a generator. Not sure the same could be said for one without.
 
https://www.boatus.com/expert-advic...e/2021/february/analyzing-onboard-fire-claims


While loose battery connections, chafed battery cables, and aged battery switches can all cause fires aboard, the most common cause of battery-related fires is operator error: reversing the battery cables or connecting them in series when they should have been in parallel or vice versa. If you're disconnecting your batteries for any reason, photograph the configuration using your phone, label the battery cables, and mark the positive lug with red fingernail polish to avoid a shocking experience when you reconnect them.


Let's face it...many systems accused of being dangerous are so because of operator error or human factor error where system design goes against human nature or capabilities....not the general concept of the system itself.

Personally...I see a pretty big push in both boating and RVing to get aways from noisy, maintenance fed generators when battery banks and inverters are becoming more viable options.

In 10 years of pretty heavy cruising...I ran my Honda 1000 to charge batteries more than I ran my 8kW diesel geneset. made it just as quiet and 8kW just to charge batteries was not great for the genset.

If I cruised in climates requiring Air Conditioning more, no question a diesel genset or 2 is the ticket.
 
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Thank you to everyone who posted. I appreciate your opinions and advice. I looked at the boat in question last week and found the sellers camera to be quite effective at expanding the size of the boat. In pictures. Going forward I doubt my opportunities will not have energy concerns addressed. The blank canvas boats are few and far between. I am almost six years into my trawler search. Had one right in the palm of my hand when Covid hit. That boat was for sale last year for over twice what I could have purchased for. Thanks again for the help.
 
We cruised for 13 seasons on the Chesapeake Bay without a generator, windless and bow thruster on a 38’ single engine Marine Trader. We did have a 1800W inverter that ran the 120v refrigerator. Less things to break the better.
 
I sailed Old School from New Orleans to Corpus Christie on the ICW last June. I ran fans off the inverter while underway then ran the Honda 2200 for AC, fans, TV, and lights. Worked just fine and was comfortable at night. Only thing I didn't like was having jugs of gasoline on board out in the sun.
 
We live onboard permanently in the South of France in a single engined 42 ft fly cruiser where it can get up to 45 degrees celsius in the summer.
I don't mean to be rude but why are you guys so pampered with electric stoves, microwave, AC units ? Why have AC units and then go outside and lie sunbathing ? You don't need all those heavy load acoutrements, never mind all the extra cost/maintainence issues.
Change to propane for cooking, plan your meals in advance ditch the microwave.
AC units ? Get out of the sun ! use neatly shaped clean white sheets cut and shaped to cover your boat so that a, its in shadow and b, open windows capture any cooling wind and c, the wind chill effect cools your boat.
Fit 2 alternators and control them with battery management system like the ADVERC alternator controllers for maximum efficiancy charging. We have 1,000 amps domestic battery bank and 300 amp separate starter/bow thruster batteries.
Our hot water comes from the engine to a heavily insulated tank fitted with a 1kw immersion for shore power and and a mixer valve to regulate (and save) hot water and that lasts us for 2 days hot water/showers or 1 bath. We make sure the boat is securely attached, start the engine and put it in gear in its 'sweet spot' around 1,000 revs every third day for about 45 minutes to reheat the water and charge the batteries. Fridge and freezer have auto change 12/220. We have an 3 kw inverter to drive the washing machine/dishwasher which is only used when when cruising so it floats the load from the alternators without reducing the charging rate. Because the Golf Du Lion is very temperamental we don't anchor out at night. When at sea cruising we're recharging the batteries and getting cooling wind, when in the canals we moor under trees for the shade.
We have 1 350w solar panel which helps the batteries run the water pump and fridge/freezer and give us up to 3 days autonomous mooring by then the admiral (who's French) will be looking for fresh baguettes and either fish, mussels or fresh oysters.
If your an eco warrior or need to be careful with your money, instead of using diesel use HVO (Bio diesel) and cut your emissions by 92%
if you can get it. It's a direct replacement for diesel, no mods to the engine are needed, it's diesel bug resistant and stays fluid down to minus 20 degrees Celsius.
We just have a different approach to stress free life I guess but it seems to work fine for us.
 
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I actually removed a working but ancient generator from my boat and replaced it with solar panels. You need to work out the energy budget for your boat. In my case I manage well with:
- 6 panels x 330 W for a total nominal power of close to 2 kW
- replaced electric stove with propane and removed three non-working AC units
- 900 A-h @12V of lead-acid batteries
- cruise only in the summer
- 2x100 A alternators
That sounds similar to my plan for a GB36. I am also thinking of carrying a Honda 2200W "suitcase" generator on deck to plug into the short power plug if the batts need a boost. I figure I will have gas for the outboard anyhow. They cost about $1200 so are somewhat disposable, but I think that with a little care it will last for some time.
 
We are in Chiapas MX, just a few miles from the Guatemala border. Laritude 14 41 N. For the last 1000 miles we have despised our propane stove, much preferring our induction hob when at all possible. It just puts too much heat into the cabin.

And we can now no longer avoid running the AC. It's hot and humid and just doesn't cool down at night. Mind you, Weebles was adapted as best I could for the tropics. Extra opening ports and hatches plus copious sun awnings for shading. Plus we have lived in Florida for years and have a place in the Yucatan where we greatly prefer natural ventilation. Even the v-berths are well oriented for any breeze.

So in 5 months of full time cruising starting in Ensenada MX (south of San Diego CA), we have about 15 hours of generator time. Not much. But I am glad I installed it. At the early part of the trip I had issues with my charging system - generator was an important backup source of battery charging. Frankly, I would have been in trouble for a while without the battery charger powered by the generator.

Boats are expensive - a bundle of small to medium sized expenses that really add up. For us, it really depends on your climate, the boats ventilation, and your tolerance.

Personally, no generator would be a serious ding in value. Do you need one? Well let's be honest, a boat is discretionary in the first place. The only time you really need a boat is when the one you're on is sinking and the one next to it isnt.

Peter
 

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My MS 34 never had a gen. I looked into installng one and cost was high, in the $25000 range. Lot of labor for wiring exhaust set up etc. In the south a/c is a must from may to oct. With my boat use, marina to marina etc, I have not missed it. My honda 2000 will run the V berth a/c or hot water heater although the engine will heat water quickly. 3 weeks before I sold my last boat the gen froze up, water from exhaust..A $10,000 bill. I told my mechanic in front of a group of dock friends that he has given me a life time warranty for any parts/repairs on my gen. Just saynn
 
You can see that many owners have found ways to bypass the genset depending on their needs. We have no genset but, we do keep that handy little Honda 2k generator in the lazarette. I would keep one aboard at all times. Example, picking up boat new to us MS350 at Santa Barbara we had to deliver to Sac Delta. Was moderately ruff Wx and a big stretch from San Simon to Monterey meant 4am to 6pm run. Well, turns out the alternator belt took that time to fail. We did not immediately recognize it but after running radar and everything else in the dark, the battery banks were down significantly, and we discovered that the 3126 CAT engine has a "power on" solenoid to keep fuel running. (A really dumb idea). So we ran the honda and I brought a 10amp charger among other things for a first cruise that we used for 6 hours to keep batteries up so we didn't end up powerless on a lee shore. This was critical. Being without power off the Big Sur coast in a moderate blow would require CG rescue and possible loss of vessel. Now our typical at anchor routine is run the Honda for 1-2 hours in morning to do cooking, coffee etc and charge batteries, then 2 hours at dinner for same reasons with some solar all day to make up the difference. Works for us.
 

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