Oil & Fuel Fuel Useage and PTO Generators

[Glenn9643]

I’ve done a search and read many threads on PTO generators, but still have questions.
I think my tractor’s PTO HP is 47 or thereabouts, and more than adequate for what I would need to power a 12-13K generator. I’m convinced right now that I can save substantially by going with a PTO powered unit, but I’m concerned about fuel useage. Should fuel consumption to operate the generator be comparable to that when clipping a pasture with moderate to light cutting requirements, more, or less? Thanks for any experience.
I also have a JD 455 23HP diesel mower that would probably be more economical to operate the the MF and might do better to try to size a smaller generator and use it. Any thoughts on this angle?
Thanks for your knowledge.

 

[frank_f15]

Please beleive me when i say, I am in know way an expert on this subject. My B2400 when run at PTO speed use about 1 gal per/hr i would imagine that reunning at pto speed it would use the same for a generator. I really don't know what a gas operated generator of the size you want would use in gasoline per hour. But i think i would get all the facts before purchasing one. YOU just might be better off with a stand alone unit. I am sure more folks more knowledgeable than i will pipe in with better advise.

 

[Soundguy]

i have a 12.5kw pto gen. the info with it states it needs 24pto hp to operate at 'full' power.. The way they state that.. I'm guessing that 24hp doesn't give you any 'reserve'.. I.E. no surge capability past the 12.5kw.

Now.. the generator hp requirement is based on electrical load. The more electrical load.. the more hp it consumes.. thus more fuel your tractor consumes. For instance , assume a 5kw 'load' ...your 23hp tractor will run your 12.5kw generator with a 5kw load about the same as your larger tractor running the same genny, at the same load.. only difference is that the smaller tractor is probably consuming just a tad less fuel.. even though the same work is being done. As a comparison.. it used to take me 5 hrs with a 5' mower and 5 gallons of fuel to mow 10 ac with my 33 hp diesel tractor. it now takes me 2.75 hrs with a 10' mower, and 5 gallons of fuel to mow that 10 ac with my 90hp tractor... less time, same amount of work.. same fuel... thus.. more fuel per hour to run that 90hp engine.. even though it is not at max load... etc

I would not get a smaller genny, thinking that you will only use the smaller tractor... I'd get the big genny, and if I had a small load.. use the small tractor for fuel savings.. and then use the big tractor for 100% load.. also.. I think an 8kw genny run at 8k continously is not as ideal as a 12kw genny run at 8kw continously.

Soundguy

 

[Paddy]

Sound Guy,

As you know, Surge vs running watts are quite different. Even in the Northern tool catalog they lable their three PTO gen's at both.

Two of the three are labled at the surge and one is labled at running. Northern Tool

I have a 45hp KAMA and want a gen set that will run a totle ele house that is 4000sqft. Northern has a 13 kW->24 pto hp and a 27kW->48pto hp. I think the 13 is too small and the 27 a bit big.

Can you see any harm in running a gen set at loads under the max rating WITH an undersized pto hp?

Patrick

 

[v8dave]

There is a definite advantage to using a larger generator than what is required for the running load--motor starting.

When a motor starts there is a sag in the voltage and the amount of the sag and the recovery time is directly related to the over capacity of the generator. The extra weight and winding (wire) size come into play. Bigger IS better. Even if you run the bigger generator on the smaller tractor. You could probably start a whole house air conditioner with the larger generator but maybe not with the smaller unit. Same goes for well pumps, shop air compressors, welders, etc. Even if you don't start large HP motors, the larger generator will reduce the amount of light flicker you experience when the heater and referigerator start.

 

[Soundguy]

</font><font color="blue" class="small">( As you know, Surge vs running watts are quite different )</font>

yes

</font><font color="blue" class="small">( Northern has a 13 kW->24 pto hp and a 27kW->48pto hp. I think the 13 is too small and the 27 a bit big.
)</font>

My pto gen is the northern 13kw unit... My step father has the 27kw unit.

</font><font color="blue" class="small">( Can you see any harm in running a gen set at loads under the max rating WITH an undersized pto hp?
)</font>

I exactly adressed this issue in my previous post. In other words.. by the calculations.. they are saying that it will take 24hp to make about 13kw.. doesn't matter if that is on a 90hp tractor and a 13kw unit.. or a 30hp tractor on a 27kw unit.

Kw load will determin pto hp needed.

I think the 13kw unit is fine except for AC.. keeping in mind big loads like stoves/welders/well, etc.. should be run singally.

As i also mentioned. i would much prefer to run a 12kw genny at 7kw than to simply purchase a 7kw genny...

Soundguy