generator vs. ?

I would like to run the A/C and fridge durring the night while on the hook.* Don't like the idea of running a generator (noise).* What is the alternative?
Can add more batteries to run the A/C and fridge at night and a bigger alternator on the engine to recharge underway?* What other controls are needed?

Air conditioners are extremely inefficient on an inverter, your only option, and add a fridge and you will need one huge battery bank to sit and run both all night. Then you will need an appropriate charging system to efficiently recharge the batteries properly so they don't die an early age. Can it be done, yes at a considerable cost in both money and real estate. Your batteries and charging apparatus is a complete system and needs to be built as such based on a lot of information and specifics other than how can I run my AC without the generator. Chuck

I am not aware of anyone who runs an AC on battery power overnight. The normal*source of power*is genset, cruise generator*or at dock.

I'm with Tom on this. I have never known of anyone running air on batteries. I don't think it's practical. Way too many batteries required. I recommend fans or a cooler environment. If you can't live with that, then buy the quietest genset you can find.*

Carey

If you don't already have an up to date noise enclosure for your generator that might be something to investigate.
Steve W.

Steve,

Thanks for the response.* What is the quietest generator or best enclosure?

Ray

Quiet to who??? You, the inhabitants of the boat, or your neighbors???

My next statement before I answer any questions is to ask a rhetorical question. Why does everyone avoid generators so much??? I know the answer has to do with noise and pollution and fuel burn. But it always baffled me when people would install battery monitoring and charging systems(wind,solar, etc) that cost 2-3 times as much as a generator and are about 100 times as complex and take up WAY more space for batteries and such. The maintenance of these systems is about 10 times as bad as well. Sailors are the most guilty of this. Anyway, I always thought it to be comical that people would be willing to go to greater expense and trouble and more maintenance and complexity just so they could still remain less comfortable and less versatile/flexible/resourceful on the hook. But, hey, they could at least brag about it....kinda like driving a Prius that solves nothing.And I do realize there are times that you should e a good neighbor and not run your generator. *The doesn't happen much around our parts down here. *But when it does, I always asked the people around us if they would be bothered by it....and everytime they are first very touched that you actually considered them and because of that are very willing to work with you.
Marin, et al, we don't have any canyons/fjords down here...I rarely hear anybody's generator at an open anchorage. *The only times I have had to consider other people is in a marina overload situation when we had dockage and no power and in very close proximity to other boats.

Alright, I am off my soapbox. Ray, all generators are gonna make a bit of noise. Usually it is just a low frequency hum for the occupants inside the boat. I would stick to the mainstream manufacturers instead of trying to seek out the one that brags about being the quietest. All of the mainstream brands offer a sound enclosure. Westerbeke, Northern Lights, Onan, Kohler come to mind. I would go with Northern Lights personally followed by Westerbeke....that is a personal opinion. I looked at a Forum member's boat down here and he has Mase generator in it's own enclosure. It was one of the quietest generators I have ever heard....and powered by Yanmar....which is a good thing! I would stay away from the Fisher Pandas simply because I have heard horror story after horror story. They likely claim to be the quietest. But I would never recommend one to anybody.

Anyway, my ignorant ramblings!!!!


-- Edited by Baker on Friday 17th of September 2010 10:11:28 AM

Baker wrote:....kinda like driving a Prius that solves nothing.

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If you've never driven or owned one, don't knock it.
I have had 3 Mercedes, a Lexus and 3 Jeep Grand Cherokees over the years and my
Prius, by far, is my favorite. Great mileage is a given but the electronics, auto
parallel parking, etc. will knock your socks off. Not to mention fabulous A/C
(electric) Blue Tooth, Sirius, etc. The seats are far more comfortable than my 500SL
ever were.* Apology accepted!


*

Hey Walt, you like the Prius for all of the right reasons....it is a good car!!!...simple as that. Wasn't knocking the vehicle at all. I was knocking the reasons why people buy them.

Just messing with you John but I do, in fact, love the car!*

"What is the quietest generator or best enclosure"

Northern Lights IMHO. I installed one without an enclosure and it was very quiet.
I can only imagine how it would have been with a sound enclosure.

(My father-in-law has a first year Prius. You will have fun when the main battery starts to go.* There were many "warnings" in advance but the dealerships (around here) are not that skilled yet and it took a long time and many trips back to get is solved. Luckily it was a couple of months inside the 5 year warantee so he didn't have to shell out 5K for the battery.)

If the amps draw was 10 amps 120 volts AC that is 100 amps 12 volts DC.* An 8-D battery is 225 amps but should not be drawn down low than 50% or 100 amps.* So it would take 8 to 10, 8-D batteries to run the AC for an 8 to 10 hour period.* This is just round extimates so don't start nick picking.* Anyway, it would take a very large battery bank.




-- Edited by Phil Fill on Friday 17th of September 2010 11:15:19 AM

Thanks guys!!! Your input and output was terrific. I am with a plan for a northern lights with an enclosure.

Ray

A genset with enclosure is going to be very quiet, especially inside the boat, and best if you can locate it out back, in the lazarette. Until I repowered my fridge, my genset could be left on when we went to bed, and we didn't realize, because the fridge was louder. This actually happenned!

This doesn't solve the neighbour problem, as it is almost impossible with a retrofit, to quiet the exhaust enough if you are in a quiet anchorage or at a non-wired dock, where you have close neighbours. You will be turning the genset off by 10:00 pm and not on again until 8:00 am in those places. Best results will be a good water muffler, with the outlet located close to the waterline. Out back allows running the gen when rafted and not exhausting between the boats.

hbrman:

I know I'll catch some flack for this suggestion but have you looked at the Honda 2000EU or 3000EU generators? Depending on how much you are actually going to anchor out, they will provide the power you need at a fraction of the cost of an "installed marine diesel generator." The PO of my boat had one which he carried in the lazarette (46 lbs, with a handle) and he used it when he anchored. On cruising the Sea of Cortez I have seen dozens of sail boaters with a little Honda 2000EU on deck, purring away. (they are very quiet) Yes, you have to carry gas but if you have a dinghy with an outbord engine you have to carry gas for that too. I'm sure you know that running a generator with little demand on it will shorten its life. The Honda EUs compensate for this automatically. (No zincs to change either.) I'm picking one up for my boat. ($800-$1000 depending on where you buy.)Honda Power Equipment - Honda Super Quiet Generators

hbrman wrote:What is the quietest generator or best enclosure?

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If you don't mind spending the money, I would say the best line of marine generators around is Northern Lights.* As John says, no generator is going to be what most people consider quiet.* But they can be made quiet if you throw enough money at the problem.

A 120' corporate yacht I was associated with back in the early 2000s had two generators, both Northern Lights.* With a famous (in the PNW) chef on board and an all-electric galley including a huge electric grill, the power demands from the boat's systems was pretty intense.* Both the generators were muffled, but one of them had a custom designed muffler and exhaust system (dry) and when the generator was running at maximum output you could go up on the boat deck and stand next to the exhaust stack and you didn't hear a thing.* You could feel the generator running--- it was heavily shock mounted, but you can't elminate all the vibration--- but you couldn't hear it at all anywere on the boat.* Given the way the boat was used during the summer months the generator was running 24/7.* They normally ran only the super-muffled one.* The other one was to take the load when the first one was down for servicing or maintenance.

But I don't think you can go wrong with a Northern Lights, large or small, but you pay for the privilege.

As to noise, there are two kinds--- generator noise and exhaust noise.* Generator noise is what you hear inside the boat.* Exhaust noise is what you hear outside.* Our boat has a 1970s-era Onan 7.5kw 2-cylinder diesel generator.* Very noisy inside the boat.* It has a sound shield which cuts down the inside noise a lot, but it's still very noisy.* Fortunately it's a deep pitch and it's a slow-turning generator, so the noise is not seriously objectionable.* That's inside.

Outside, all you hear is the water splash of the exhaust and a very faint putting sound.* Twenty, thirty feet away and you don't notice it at all.

On the other hand, we've been moored to a marine park float and have had other boats on the docks with generators that themselves seemed to make little noise but the exhaust was extremely irritating.* A loud, hollow, drone that you could hear clear the other side of the bay.

So you can buy and install a quiet generator and piss everyone off for a half mile around you because the exhaust system is noisy, or you can have--- as in our case--- a pretty noisy generator that outside the boat is barely discernible.* Or you can get as quiet a generator as is possible and then put a really effective exhaust system on it and have the best of both.

*


-- Edited by Marin on Saturday 18th of September 2010 09:59:16 PM

Marin, I thought those old 7.5 2 cylinder Onans were high speed??? I just assumed since they are only two cylinders that they would need the extra revs to make that kind of power.

-- Edited by Baker on Sunday 19th of September 2010 08:44:44 AM

Hiya,
** Used to have the 7.5/2cyl. Onan.** Sounded like a cage full of monkeys each with a gallon can 1/2 full of ball bearings shaking them up and down.* No sound shield.* Could barely carry on a converstion in the salon while it was running.
** Slow speed I'm pretty sure as there's NO way that thing was turning much more than 1800 RPM.* Can't remember actual published speed of the Onan but I think the high speed genny's turn in the neighborhhod of 3500 RPM.

Baker wrote:

Marin, I thought those old 7.5 2 cylinder Onans were high speed???

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I just checked the Onan MDJE manual on the GB forum manuals section and the rpm for 60hz is 1800, 50hz is 1500.* I believe the "high speed" generators are 3600 rpm for 60hs, 3000 rpm for 50hz.

Our Onan is loud inside the boat but it's not an objectionable loud, at least not for the way we use it.* We only run it for an hour a day on the days we aren't going anywhere on the main engines.* An hour is sufficient to heat water that will last the entire day and into the evening and throw a charge back into the batteries.* So the noise inside the boat is tolerable for that period of time.* If we had to keep air conditioning going or if we had an all-electric boat, the Onan would get very tiring after awhile inside.* Outside there's just the water splash of the exhaust.

*

My 12.5 Westebeke is in a sound shield and has a waterlift muffler. It is well isolated by the rubber mounts from the stringers. Very quiet. I have recently been on a vessel with two gensets - one a Westerbeke and one a Norhthern Lights. Both were quiet. Why - they were well thought out for the installation. The manner of installation for the mounting and exhaust systems is crucial for quiet operation, no matter whose brand.

Using batteries to run an Air Cond at night is simply a matter of system choice , and price.

There are at least 4 different methods used on trucks to keep the sleeping quarters air cooled during down times .

This , depending on the drivers preference , can be a challenge as many prefer to sleep day time and drive at night , so the solar gain on the sleeper will be high.

The problem is volume and insulation.

A truck sleeper is smaller than the owners cabin on most boats , and probably better insulated.

However the night , no sun load should be handleable.

The problem is trucks will operate the engine ,next day , 8-12 hours and that is long enough to recharge a large batt bank. A few hours of cruising or noisemaker will not come close.

You might be able to use a good custom noisemaker with a 300A 24V alt during the day , to time shift the noisemaker stench and noise , but you would need both a Sine Wave inverter for efficiency and spiral wound deep cycle batts to be able to absorb the charge rapidly.

Big bucks.

Another solution could be home made eutetic plates , freeze them rapidly with a cast iron (YORK) CAR 10HP COMPRESSOR in a few hours of run time , and suck cool air as long as it lasts. Cabin size and OAT will be the concern.


Can you do it Sure , but for less than the cost of the battery cables you can get a gasoline Honda to operate the std boat air system.

The unit simply is ploped in the dink and trailed astern 30 ft.

There far far quieter than the installed diesel sets , so the folks in the harbor MAY not use it for target practice.

If you are prepared to forgo aircon at night for fans, and apart from the odd stinker, that is certainly ok out on the water, as our cruising grounds here off Brisbane would compare with the warmest the US coast could throw up I think. We are totally 12v and manage with just solar and the engine during the day, and an Airbreeze wind charger whenever there is a breeze, day or night. It can also augment the engine and solar when on the move depending on wind and travel direction.

Gensets in an enclosure are known for being ignored for routine maintance. THe enclosure prevents you from SEEING things that you ought to be noticing, such as a hose falling loose, etc. before catastrophic failure.

Just realize when you get an encosure you also have added obligation to REMOVE IT often to inspect the genset.

You could try the genset without the enclosure first and see how the noise it. Thats what I did on my boat. Thought I needed an enclosure in my list of trawler "needs" before purchase but this boat's genset is not enclosed. Bought it and tried it. The noise is completely tolerable and I like having it exposed for easy visual inspection.

R.

"You could try the genset without the enclosure first and see how the noise it. "

This could be difficult as many base pans used to seal the unit are mounted under the noisemaker.

You would have to lift the unit , or purchase the bottom of the set , in the hopes of not using it.

fill your bilge with batteries to run an airconditioner capable of cooling your boat for any length of time.

Actually it really depends on weather you wish to air cond the sleeping cabin or "the whole boat".

The tech is HERE , even to do it with tiny battery drain.

The system used Eutetic plates , a large compressor to freeze the plates quickly , engine or noisemaker belt driven.

FF wrote:

"You could try the genset without the enclosure first and see how the noise it. "

This could be difficult as many base pans used to seal the unit are mounted under the noisemaker.

You would have to lift the unit , or purchase the bottom of the set , in the hopes of not using it.

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FF, we gotta guy in our area that makes "soft sided" noise enclosures. *His main business is noise suppression at the plants around here. *He built one for my last boat for $600!!!! No base pan need. *Everything is held together with velcro. *Anyway, he did an excellent job for a relatively small amount of money and it provided inspection "ports" that you just "tore off" via velcro. I'd do it again in a heartbeat.

That sounds very interesting. Are they self supporting or do they require a frame of some sort?

If you can pm me with a contact for the guy I would appreciate it. We have some applications where that might work very well.

I'm with Rick on this, Baker what is his contact info?

Most electrical generators provide electricity by turning a dynamo with a fueled engine, but an inverter is a series of coils that convert stored electricity into usable voltages. Inverters require batteries, or a power source, and a generator does not (as it is the power source). The most common use for an inverter is with a solar power system, for conversion of the DC electrical power to usable AC. Most generators will include a proprietary inverter in their design, to temper the electricity produced by the dynamo. Determining which technology is best will depend on the power requirements and which fuel is practical.