How much does fuel does a 11kW genset burn?

MapisM

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The title says it all, really. Can anyone give me a ballpark number?
I understand it's also load-dependent, let's assume at around half load, if that.
No need to run the airco while overnighting at anchor! :cool:
 
Based on the standard figure for a non-aspirated engine of 240gm/kW/Hr, a consumption of around 2.5l/Hr is likely. That agrees with a HFE 12kW genny I had in the previous boat.
 
The title says it all, really. Can anyone give me a ballpark number?
I understand it's also load-dependent, let's assume at around half load, if that.
No need to run the airco while overnighting at anchor! :cool:

11kW Onan uses the following-
No load - 0.9lph
1/4 load - 1.5lph
1/2 load - 2.2lph
3/4 load - 3.0lph
Full load - 4.0lph
 
I’d agree with that - ours was about that on Breaking Bad and seems to be the same on the new boat - we’ve run it for around 40 hours in the last two weeks and the fuel gauge shows 125 litres consumed. Generally we’re putting on the watermaker, hot water and bits and bobs on for an hour or two - so about 5kw mean.
 
Thanks folks, that's all I needed to know at the moment.
Based on those numbers, it's not even worth considering the genset which I'm running for a couple of hours a day, in the context of understanding whether the engines burn 150 or 170 or whatever liters/hours... :ambivalence:

Btw, the new to me genset is a Kohler 11EFOZ.
Not that I think this makes any meaningful difference in terms of fuel burn, but it's one of the boat bits which I didn't yet investigate properly.
The engine is a 3 cyl Yanmar with a 1.64 liters displacement, but that's almost all I know about it... :o

Any experience/information/suggestion about the thing is more than welcome!
 
Thanks folks, that's all I needed to know at the moment.
Based on those numbers, it's not even worth considering the genset which I'm running for a couple of hours a day, in the context of understanding whether the engines burn 150 or 170 or whatever liters/hours... :ambivalence:

! That’s context for you :) we never noticed the lph of the generator on our last boat as it got buried in the bad news of the fuel receipts, but now it’s about 50% of our total consumption....
Still, we’re out of marina now so saving many £ - the 90lb anchor is paying for itself :)
 
Yep, I would have said 2-3 lph but you have better answers above. If you want a parts list to install Maretron fuel flow/return meters and a dedicated n2k backbone/display to measure consumption and cumulative burn, just let me know:encouragement::cool::D

I'd make the observation that impellers fail at very consistent hours, in my case about 375. It is worth knowing that and changing it just before. Then it doesn't spoil a lunch.
 
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Yep, I would have said 2-3 lph but you have better answers above. If you want a parts list to install Maretron fuel flow/return meters and a dedicated n2k backbone/display to measure consumption and cumulative burn, just let me know:encouragement::cool::D

nice one John :D

actually I have a cheaper solution on test (N2K) but P has to wait for a couple of weeks before I report full success (although I'm sure he's not interested :p )

cheers

V.
 
Combine it with an AnCam. Then he'll be interested :D:D

yeah right...
John, one step at a time, he seems to be happy at planning speeds, so who knows maybe next winter he'll start looking at ancams as well :D
fuel flow meters for the genset or would they do the big engines as well.

Id like some way of measuring fuel flow on Seralia but there are no engine electronics.

Jez,
I'm testing 250lph ones for the engines (there are 500lph ones as well as larger), fitted the one, works fine (only boat is still on the hard) fitted the second and I'm now together with the company trying to sort out engine ID issues (both seem to report 1 single engine)
It's a software issue should be fixed next week, then I'll post a new thread (or revive one of the older ones I've started...) and report.
You will need an NMEA2000 device/gauge/plotter/whatever to view it though. A simple Garmin GMI10 works fine (that's what I've got). Tested it on a B&G 7inch plotter/multi thing, worked as well.

cheers

V.
 
Hi Vas,

Are you using Fuel View by MassFlow senders?

Do you know if raymarine do a unit similar to the Garmin? I don't mind the gamin but the rest of my kit is raymarine.
I have ST60 Multi displays - I wonder if they will display the data
 
although I'm sure he's not interested :p
LOL, you know I am, Vas.
In fact, you also know that as soon as your setup will be ready, you already have a first client waiting!
As long as you don't try to sell the system in package with the AnCam, that is... :cool:
 
I have ST60 Multi displays - I wonder if they will display the data
I've got the same stuff, and I'm afraid they don't handle N2K protocol, J.
But tbh, I don't see that as an issue.
If I should fit fuel burn displays, I'd rather have them dedicated and separate from all the navigation stuff.
Otoh, for me if there's a moment when such instruments would have been useful, it's now.
Once in CF, I might as well forget all that. Out of sight out of mind, you know... :p
 
Still, we’re out of marina now so saving many £ - the 90lb anchor is paying for itself :)
So are we, and not just to save money - secluded anchorages are a much better place to stay, compared to any marina!

And apropos of anchors, funny you should mention your 90lb one.
I was also used to that size on the old lady (two of them, btw), and I was a bit concerned about the 25Kg Delta of the new boat.
Then again, I thought that since it worked for 14 years, I could as well give it a try.
And as it happens, yesterday night, we had our first experience in a bit of a blow. Nothing too bad, but enough to make the boat swing a bit and put some snatches on the chain - which I snubberized anyway, if that's a word that makes sense.
Now, I was very pleased to see on the plotter track that the boat didn't drag one bit.
Which sort of strengthens the impression I always had that anchors are overrated here in the asylum! :rolleyes:

Here, I said that.
If one of the next days I will post about how it feels to wake up in the morning with the boat ashore, you will all know that I called for it... :D :p
 
Hi Vas,

Are you using Fuel View by MassFlow senders?

Do you know if raymarine do a unit similar to the Garmin? I don't mind the gamin but the rest of my kit is raymarine.
I have ST60 Multi displays - I wonder if they will display the data

as P says, doubt they'll do it J...
not sure what fuel view and massflow are btw.
BTW, I wont be selling anything!
I just got the two senders for free in order to help them develop the s/w and test it on board a N2K network.
If you want a set or three, you'll have to talk to the guys, I'll give you details and I'll try to get them to have a special forum price.

I've got the same stuff, and I'm afraid they don't handle N2K protocol, J.
But tbh, I don't see that as an issue.
If I should fit fuel burn displays, I'd rather have them dedicated and separate from all the navigation stuff.
Otoh, for me if there's a moment when such instruments would have been useful, it's now.
Once in CF, I might as well forget all that. Out of sight out of mind, you know... :p
that's why I believe you wont need them P ;)
Although tbh if they are less than .5K per engine (don't remember the prices but I think they mentioned something like that) it may pay off by simply letting you trim and check and optimise runs. OTOH, having 1K nm under your belt by the time you get to CF, you'll probably have a v.good idea of what your engines burn at various setups either P or D

cheers

V.
 
BTW, I wont be selling anything!
Yeah, I know, Vas.
In hindsight, I guess that my comment "As long as you don't try to sell the system in package with the AnCam" could be misunderstood, but it was actually just meant as a joke in reply to jfm post #9! :rolleyes:

That said, I would be delighted if you could find the time to come to CF and help me install your system also on my boat, obviously refunding you all the related costs. In fact, I believe you are right in suggesting that they can be worth fitting even if the boats is mostly used for short trips.

Anyway, if you would interested in a Sardinian break, gimme a shout.
It would be a pleasure for us, also regardless of the possibility to install the system on my boat! :encouragement:
 
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As a rule of thumb all gensets burn about 0.4 lt per KWh. in the middle of their range of output. A bit more at the ends of the range. They are a bit like propulsion engines. Fuel burned = power delivered.
 
indeed, consumption is neglectible compared to the engines

we have the slightly bigger Kohler 16,5Kw, 4cyl Yanmar, full mechanical,
so far, after 27years and 4000 hrs (each) both still run smooth,
service so far apart from filters and impellors;
we had new raw water pumps, (very cheap from Ceresoli) and rebuild / grease the solonoid on each engine starter motor,
and replace the corroded and warn "woven copper wire" ground connection between yanmar engine and electric controll box.
A few years ago Ilko replaced the nozzles from the injectors, after that, smell and smoke was a lot less.
 
Thanks B, all very good to know.
I believe that our 11kW is still of the same generation as your 16.5, 100% mechanical, and aside from being smaller (3 vs. 4 cyl engine, with correspondingly smaller electrical side) it's pretty similar.
So, based on your numbers, my genset might well outlive me, having made 800 hours so far in 14 years...!

Just a couple curiosities, if you don't mind:

1) do you usually let your gensets run completely unloaded for a couple of minutes, before turning them down?
That's a suggestion which I found in the manual of my previous Onan, but I don't see it in the Kohler manual.
Though it might well be there, and I just didn't find it yet...

2) are also your gensets amazingly fast to start up?
My previous (much smaller, at 6.5kW) genset always worked perfectly, but it took three seconds or so to start.
Now, this Kohler thing seems to be running on the split second when I push the button!
 
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