How Many HP to Run 18kw PTO gen?

[GarryinNC]

I noticed a 18,000 watt pto generator for sale. How many hp to get full output from it? Could you get say, 9,000 watts from it with half of the required power?

Thanks,
Garry

 

[coonie minnie]

Good rule of thumb is 2 tractor hp for each KW. Dedicated gen sets can be closer to 1.5 hp to kW.

 

[Janicholson]

40 is in alignment with coonie's answer. Maybe you could, but it might have difficulty with starting some loads, and keeping frequency. It might also be tough running a tractor at near full RPM and power. Many little "depends on" issues. Jim

 

[GarryinNC]

Thanks for the fast replies. I have always thought that it seemed inefficient to run a tractor at 540 pto rpm to power a generator, but we rarely need one for a very long time. Storing a pto generator and not having to worry with an engine would simplify things somewhat. They are asking $750 for it. Do not know the brand as yet.

Thanks,
Garry

 

[Phil9N3667]

Uneducated guess would be 50-60 H.P. for full load. Friend of mine runs a 27KW unit with a 200 plus
H.P. JD, but only because of a 1000 RPM PTO, cut back to get 540 and the tractor has all the auto
shutoff features. This way, he doesn't have to keep an eye on it.

 

[casecollectorsc]

Got a 15kw here...use to use a 60 hp tractor and would open the governor when running the silo unloader with a 10 hp motor on the unloader. Didn't pull real
hard, but you knew it had a load on it. Guess if I was you...60-65 hp.

 

[Destroked 450]

Rule of thumb is two engine hp per KW so 18 KW equals 36 hp plus drive line loss, best to have 40 hp min.
No sure how the hp requirements are for pulling a 18 KW gen at half load, you can't power a modern home on 9 KW but it mite work if your selective on what you turn on, it would work a 18 KW gen hard to power an all electric home.

During 09 ice storm we ran lights, tv, frig, table top grill and a small heater on 5500 watt gen, water pump if grill and heater where off, after water was drawn we turned the pump off and turned on the water heater (that loaded the little gen), after water was heated turn off the water heater and pump the water into the tub, turn off water pump and move the little electric heater into the bathroom to bathe.
It was ten days before the power came back on but we where better off than ones that didn't have a gen.
We have a gas log insert for backup heat now.

The backup gen for my poultry barns is 75 KW and is powered by a 145 hp diesel.

 

[Billy Shafer]

An engine driven 17.5 needs 32 hp. I would say 40 would do it.

 

[Philip d]

I'm voting for 40 as well. We run a 50 kW on a dairy
with 2 houses connected as well and when enough
things are running its moaning pretty good. A 3505
Massey will power it @90 pto hp?

 

[RalphWD45]

Northern tool, and equip. has a 27.500 for $3000., that they claim needs 48 hp to run it! I guess a WD45, would get a workout, with it, but would be cheap on fuel.

 

[MarkB_MI]

Yes, you can run it with half the required horsepower as long as you don't exceed half the rated output.

 

[Richard G.]

Garry, that sounds like a reasonable price if it works well.
Richard

 

[JDEM]

I ran my entire household many times with a 15KW PTO generator hooked to a little Cletrac HG. It has 20 horse maybe? Figure 550 watts per
horsepower. Ran the same with my Case VAC also.

 

[Bret4207]

I've run my 25Kw with 30-45 hp with no issues.

 

[Texasmark1]

1 HP = 746 Watts. Figure 50% efficiency for the system. 18 kW/746 = 24 hp x 2 if considering 50% efficiency = 48 hp....that means 48 hp on
the PTO when running, not a PTO that has the capability of 48 hp........that is if you are using 100% of your generator's rating. If the system
efficiency is 100% (which it can't be but for a number) it would only take 24 actual PTO hp.

Only running your gen. at partial load, figure some number for efficiency and do the math.

 

[JDEM]

I've got a dozen generators here with their own engines. All are sized at 500-540 watts per rated horsepower and all work as advertised. 13
HP/7000 watts, 8 HP/4000 watts, 10 HP/5000 watts, etc.

Running my entire household with a 15KW PTO generator hooked to a Case VAC or my Oliver HG is not a perfect test since I don't know what
total amp draw was. But - we had an electric water heater, well-pump 1 HP and 220 volts, refrig, freezer, furnace, lights, TVs, computers,
plus some stuff in the barn. Neither tractor ever worked hard. Cletrac is a max of 25 horse and the Case a max of 21 horse.

I also did a lot of arc-welding in the field with my PTO generator and Case VAC. 50 amp/220 volt max rated but who knows? I know I have
welded at max setting and the tractor just grunted a little and kept on going. Let's say I got up to 10,000 watts. That comes to 476 watts
per HP.

 

[JMS/.MN]

I have a 25/45 Winpower pto unit. The D17 (53 hp) handles it well, but the 3020 (70hp) doesn"t grumble when you start an extra 7 1/2 or 10 hp motor.

 

[buickanddeere]

27HP will squeek by at 100% load. Start the largest electrical motor loads first.
A lot of gensets run cold and wet stack due to being over engined on the prime mover and underloaded on the generator side. Monthly Run ups to "test" a diesel genset without load is not wise policy. Flip the transfer switch and load it.
If somebody complains have them put it in writing and sign that they want testing and verification of safety system reliability stopped. Usually ends the conconversation right about there .

 

[Dr. Walt]

Only ONE if he's a strong Horse and you've got the treadmill & gearing set up properly. LOL


:>)