WHAT IS A GOOD GENERATOR ??

[a64pilot]

Originally Posted by Fast Tack

That is a great point about eliminating a potential problem by having an AC Air Conditioning Water Pump. Off hand do you know what size or model of the March water pump your using ?

It’s the same as the one I use on my 16K BTU airconditioner, it does pump more water than the original pump did, but I called Nexgen about it and they said that wouldn’t be a problem, and it seems to not be. Sorry forget the number, I use the same pump for my little 6K AC too so that one spare covers both AC’s and the generator.
I think this guy but only going by the way it looks http://www.defender.com/product.jsp?...240&id=2214389 The smaller one would likely be better sized
An unusual thing about the little Kubota is it has no water pump or thermostat, it’s cooled merely by thermal siphon. Meaning hot water rises and is cooled by the heat exchanger that is on top, then cooler water sinks and it sets up a convection current this works well for engines that run at higher RPM always and usually under a load, not so much for engines that are idled for extended periods etc, and widely variable loads, you really should have a thermostat then.
It is the way even automobiles used to be cooled years ago, and is why older cars the cooler water was first introduced into the cylinders and then flowed to the head, which is backwards of course as most of the heat is in the heads and they should be cooled first. But it set up a convection flow.
GM with the LT1 V8 in 93 went to “reverse” cooling and water now flows from the top down like it should, I know my Duramax Diesel was the same way, and assume “reverse” cooling may be more of the norm now?

[a64pilot]

Originally Posted by travellerw

Could you give us a rough idea of cost.. I couldn't find it on thier webpage.

I think about $7K all in, but that is just a guess. A quick Google showed street price to be $5,700, but I bet that is without a sound shield.
One I got came with everything needed except thru hulls and hoses.

[stormalong]

You sure got a lot of answers. You did not supply a lot of info.

What size boat?

What do you need the generator for?

Do you have air conditioning or other heavy loads?


I love solar to satisfy my electrical needs. It is quiet, maintenance free and needs little attention - just keep them clean. They do not heat up the boat and don't need fuel.

If you have the space for them and only DC needs IMHO it is a far better option.

[JD-Odyssey]

My wife and I are have been year-round liveaboards in Annapolis, MD for the past 13 years (just retired this past year so we couldn't do the snow-bird thing while I worked). I had a Northern Lights installed about 10 years ago as insurance in the event we lost power at the marina for an extended period of time (happened a few times during high water from storms and freezing weather downing local power lines). I wanted something that was low RPM, reliable and diesel powered. An added benefit is it also extended our sailing season into late Fall and hot days summer with A/C. It's been very reliable and very low maintenance. That was the rational for our choice and it's worked out well for us.

[Eder]

I like to press a button & have enough power to light up the anchorage. My Northern Lights does this easily and with the GenSup I added most other boats are unaware my gen is running.
I have solar as well but that's only fun when I don't need 30 amps

(breakfast time we have toaster, charger, Keurig, watermaker, hairdryer, water heater and electric skillet...the air conditioning hasn't yet started...no camping please!)

[warrior 90]

Originally Posted by stormalong

You sure got a lot of answers. You did not supply a lot of info.

What size boat?

What do you need the generator for?

Do you have air conditioning or other heavy loads?


I love solar to satisfy my electrical needs. It is quiet, maintenance free and needs little attention - just keep them clean. They do not heat up the boat and don't need fuel.

If you have the space for them and only DC needs IMHO it is a far better option.

I agree, before we start the typical Ping Pong and filling pages contest about what is best.....
I believe first we should specify the requierments and needs.

[Jeanneau 45.2]

I also have the NextGen 3.5 Kw. Very happy with it and would buy another, but understand it's limitations. Given mechanical speed control, single cylinder and simplified electronics, while rated 30A @120V AC I can only consume 22 - 23 amps before the voltage begins to oscillate +/- 10 volts while running my air con. Simple resistive loads like the water heater do not oscillate. FWIW, I generally run continuously between two to four hours and rack up about 50 hours a month. Parts availability and customer service are first rate.

[travellerw]

Originally Posted by a64pilot

I think about $7K all in, but that is just a guess. A quick Google showed street price to be $5,700, but I bet that is without a sound shield.
One I got came with everything needed except thru hulls and hoses.

Holy smokes.. Way more than I thought...

Makes no sense for me. I have 1000W of solar and 400W of wind.. It would make WAY more sense to put the money in to LifePO4 for me... Although my Honda 2000 is loud, it uses about the same fuel as the NextGen.

I appreciate the reply though..

[Pelagic]

Originally Posted by Dockhead

Yes, I agree about conversion efficiency, and I don't care that much whether I generate AC or DC power.

But a DC generator like this has some profound advantages. Note that I do NOT list "getting DC power directly" as an advantage

* Can run at different RPMs so that engine runs with a more healthy load for a given RPM.

* Cutting back the revs when small power is needed, will be quieter and less wear on the engine, not to mention more healthy.

* Using a standard school bus alternator (or a pair of them) is cheap, easy to repair, easy to carry a spare for -- in other words, easier to keep running in remote locations.

* Separating engine from generator makes both easier to get at and service.

Making it into a good battery charger is trivial -- a good external controller will do that -- Balmar or Sterling.

Interesting notes DH but I would like to explore a bit further.

Are most of your high load consumers (Air Cons/Induction Cooker/Large output Water makers, Charger-inverters etc) , more readily available and with a wider array of choices in AC or DC?

If AC..... then the benefits of them also working with shore power and a considerably lighter, simpler, cabling system and spares also favors direct AC generation.

A large capacity DC generator has too much of a side torque on the matched primary mover to be good for the engine's crankshaft bearings, so a direct in line bolt on generator would be recommended.

Having a large capacity DC alternator on pulleys off of the larger main engine makes a lot more sense when motor sailing and is what most of us have.

But most of this discussion is what works best when stationary (At Anchor or Marina)

At AC 50hz, running the engine at a steady 1500 rpm is close to the optimum conditions for a 3 cylinder diesel as is my Northern light 10kw.

Designing soundproofing and vibration control for a set rpm is much more effective.

Our large house banks are really there for engineless service so when recharging at anchor, our generation loads can be balanced with the intelligent use of consumers.

So unless all your consumers are DC, you need AC generation or a large enough amount of Invertor/charger combos

[a64pilot]

I think Dockhead is thinking as I did, but didn’t go there due to costs.
Idea is to have the Queen Mother of battery banks, a huge Life-PO most likely, couple that with a really large charger or chargers and a monster inverter. That way you can run anything you want to off of that monster bank and shift recharge time to when you want to. Want to cook with electricity but don’t want to bother others in the anchorage? No problem the big bank allows you to do so, and maybe your leaving later that day and are going to do significant motoring, so why not let the big propulsion motor recharge the bank and not run a generator at all?
A DC powered Boat makes sense as of course AC is just an inverter away, but I gave it up as it’s a Science project, and outside of my budget and time line.

[a64pilot]

Originally Posted by travellerw

Holy smokes.. Way more than I thought...



Makes no sense for me. I have 1000W of solar and 400W of wind.. It would make WAY more sense to put the money in to LifePO4 for me... Although my Honda 2000 is loud, it uses about the same fuel as the NextGen.



I appreciate the reply though..

I believe a Northern Lights 5 KW is at least twice that in cost and weight.
I think 5 KW is the smallest NL

[daletournier]

I would like a built in generator. My needs are minimal, and although the above is relatively compact, light and cheap it's still, huge, heavy and expensive compared to a 2kv Honda.

I dislike using gas, I don't like the fumes but don't need more than 2kva. It would be great if there was a true diesel Honda equivalent that could be built in.

[salar]

You might want to look at Paguro

Seawasp Australia - Paguro Marine Generators

We have 5000 model for 3.5 years. Love it.

[nwdiver]

Originally Posted by daletournier

I would like a built in generator. My needs are minimal, and although the above is relatively compact, light and cheap it's still, huge, heavy and expensive compared to a 2kv Honda.

I dislike using gas, I don't like the fumes but don't need more than 2kva. It would be great if there was a true diesel Honda equivalent that could be built in.

You could probably replace the gas motor on a Honda with a little single cylinder diesel, a friend has a scuba compressor with a hand pull diesel that runs fine but is louder than the gas equivalent, but it is a dive compressor which is louder than the motor......


The reason there aren't any common 2-3kw diesel gens sets is the little Hondas hold the market and are alott cheaper.......

[Dockhead]

Originally Posted by john61ct

. . .
No, you set the pulley ratio so 70-80% of rated amps is produced at low constant rpm, long as enough torque is there when alt(s) get loaded down.

Why would you operate it at constant RPM if you don't have to? This would work if the alternator is small in relation to the engine's total power, but if they are better suited to each other -- as they would be if you bought the engine primarily to generator power -- then you will really want to vary the engine speed.

I guess you could have a couple or three different regimes depending on what kind of loads you have, and just leave the engine at the corresponding RPM. But some kind of automatic control would be really useful.

Originally Posted by john61ct

Yes could be attached to the propulsion engine if there's room. I was thinking dedicated in place of a traditional genset.

I do have a large alternator capable of generating bulk power, on my propulsion engine -- a 110 amps * 24v Leece Neville, which can make around 2.5kW. It's extremely useful even when you have a really good separate generator. Just to name one good thing about this -- the generator gets backup so it's not a single point of failure. Another -- free power when you're motoring.

But the OP wants and I would certainly want a separate generator, with a smaller engine which would be more efficiently -- and more healthily -- loaded while generating power for extended periods.

Solar is great, but unless you have a catamaran or don't care about windage, it's hard to have enough of it to stay in business on an electric-intensive boat.