PTO Generator Question

Looking to find a generator before winter sets in. Want one big enough to run deep well and whole house. If you have a 540 rpm PTO generator and a 1000 rpm tractor, can you use an adaptor and run the tractor at 1/2 throttle? How many HP do you need to run generator? See a few neighbors with them, and the smallest tractor I've seen on one is a 4020. I was thinking about fuel consumption, 1/2 throttle versus full throttle. Chris

Like everything else, it depends on the load. I have a 15KW constant/25KW intermittent alt. which will start a 10hp motor, but it makes it grunt. The 60hp tractor does it, I don't know how much it actually takes. Tried it once with the 4020 at half speed - no good. For just general lights, heat, etc. I run it with an AC "C" no problem- 540 pto rpm/1350 engine rpm, or with the 2520 set up like you mention. I did take it and the welder to the field once to weld on a bulldozer and ran it with the C easily.

While you're on the righr track finding the HP required to run a generator at 540;
you also need to find the rated HP of the tractor that you're gunna use at the rpm to run a 1000 rpm shaft at 540.
Clue..... it ain't 1/2.
While I would bet the price of a new well pump on it, I wouldn't bet the price of two bulk tank compressors and $5000 worth of milk on it.

You can do the 1000 Rpm on 540 it actually does not save that much fuel though you need 2 HP per KW I am guessing you could run the entire house with a 15 KW you have to figure out the watts of every thing you want to run then had them up

Check out Tiger-power.com. I have the 15 kw & it runs almost the whole house. It does not run the central air conditioning. You could go bigger for that.

We had a 15 KW WinPower that we used for years on our West Michigan diary. It ran the whole house as well as the barn as long as I limited how many items I ran at a time. I never tried running the bulk tank and the silo unloader at the same time, but the gutter cleaner could run with the vacuum pump. If it looked like we were going to have to run it for very long we put one of the 3020s on the generator, but for shorter periods we just put the 52 B on it. The main farm pole was right next to the garage and the B would fit in the garage but the 3020 didn't so it worked pretty good to set the B up and let it go. It handled the load, just not nearly as smoothly as the 3020 would.

If you figured things correctly, along matched power to current demands - yes - you could adapt a 1000 RPM PTO to a 545 RPM generator and run the engine at a lower speed. But, that probably puts the tractor out of it's peak torque and efficiency curve.

It takes around 1 horse to make 500 watts of power. I've got a 15KW PTO rig I've hooked many times to my 32 horse IH tractor and it did fine. Also ran it on my little VAC Case. Can't say I ever used it at full capacity though. Ran my entire house on it, ran a 200 amp welder, etc. No problems.

A large PTO generator is never going to be efficient unless your're working the tractor in it's peak range. That's the curse of making your own power. Usally electric demands are intermittent so overall efficiency is low. A 3000 watt generator with a 5 horse gas engine will run a lot more efficiently at 3000 watts than a 30-50 horse diesel tractor hooked to a PTO generator - if only making 3000 watts.

The only way to get top efficiency when the demand is not steady is to use a battery bank and inverter. Run the bank until it gets low, then charge it up with a diesel generator sized properly to run at full efficiency to recharge the bank - and then shut down.

Another option - is to use a tractor hooked to a PTO DC generator and then through a large inverter. This way, you can run the tractor at any RPM and still get 60 cycle current.

On a direct drive generator, you will need 2hp per KW rating. You are going to be looking at a gear reduction generator setup, so I would not know HP requirements there. Most generator heads run at 3600RPM to get 60 cycles and 60 cycles is what youu need in the USA to run household appliances, air condintioners and such. Now, what is the fuel consumption of your tractor? 2-3 gallon per hour, loaded? You can buy portable 20KW generators that will burn about 1.5-2 gallon per hour and should run a house. You can get a 15kw standby that runs on natural gas or propane that checks itself every month, and starts when power goes out, even if you are gone.
Whatever you go with, make sure it is a decent one. There are a lot of "cheap" generators on the market that put out "dirty" electricity and will fry delicate electronics in newer furnaces due to spikes.
Jim

We have a PTO Generator that is set up for a 540 rpm PTO. We have ran it several time with the 806 and put the adapter shaft on the 1000 rpm shaft and it works just fine. Ours is a 24KW model I believe. Don't know how "efficient" it is, but it sure beats the heck out losing everything in the freezer and going without water for the livestock. It will run the entire place with no problem. Two houses, electric water heaters, washing clothes, running a 220v water pump. Can do all the daily chores of cooking, cleaning. Can even fire up the welder if we need to. GOOD investment.

1-1/2 HP per kilowatt continuous but there needs to be reserve for motor starting.
For 2-10 seconds a single phase motor will draw 4 to 12 times it's nameplate rated current.
So 2HP per KW is a good rule of thumb for a 25KW generator making 20KW-25KW.
Running a 540 rpm generator with a 1000rpm tractor slowed to 54% of rated. Is not going to save a fortune or cut fuel consumption to 1/2.
Running a 1900rpm tractor at 1026rpms will leave it at 73% of the rpm required for peak torque/peak efficiency.
So as previous posted have stated. Good idea but it doesn't work and it costs plenty in repairs.
Any decent pto generator has a 1800rpm rotor. The low end pto generators have a 3600rpm rotor.
Make certain all windings are copper. You would be surprised to know how many generators are cheaper because the windings are made of aluminum.
Next question. How are you tieing this standby generator to your hydro service?