PTO generator vs. Stand Alone

   / PTO generator vs. Stand Alone #1  

CurlyDave

Elite Member
Joined
Dec 25, 2005
Messages
4,287
Location
Grants Pass, OR
Tractor
JD TLB 110
I need a generator for two purposes.

1. Powering a 5 hp well pump for up to 30 minutes at a time (~4kW) over the next 12 months, and after the house construction period,

2. Serving as a backup generator for the house we are building. No idea of kW rating, but it should run reefer, freezer, and some lighting, computers, and TV. It will not have to run the well pump, since we will eventually have a storage tank which will work by gravity.

I think the choices I have are PTO generator vs. Stand Alone and then the fuel type. Gas, Propane and Diesel generators are all available. Other equipment we already have uses all three types of fuel, so there is a reason to keep all three types on hand.

My tractor is a JD 110 TLB. Do I have to remove the backhoe to use the PTO? If so, this alone would disqualify the PTO generator.

Anyone have an idea of relative costs, ratings, and expected lifetimes of various types of generators.

Anything else I should know about them?

Thanks.
 
   / PTO generator vs. Stand Alone #2  
Dave,

I have considered the same question. I have a Kubotoa 5030 with sub-frame BH, and I have to remove the BH to use the PTO.

Even if I did not, I decided against the PTO gen for one principle reason: Household 6

Since my reason for a genset was to provide semi-seamless back-up power, I know that my wife would not take kindly to the setup tasks required of a PTO system. (As a worst case scenario, at 0 dark 30, in a driving rain or heavy snow, and me not at home.)

Propane is derated when compared against gasoline or diesel. Gasoline gensets are not (generally) as durable as diesel.
You can buy home heating oil(HHO) quite a bit cheaper than on-road diesel for a diesel genset. "Power-Sevice" it, and use it in your tractor as well, and you get a pretty freshly cycled supply for both the genset and the tractor.

RFB
 
   / PTO generator vs. Stand Alone
  • Thread Starter
#3  
As a worst case scenario, at 0 dark 30, in a driving rain or heavy snow, and me not at home.

Total agreement there. I have the same thoughts. In fact, even if I am home I don't want to be taking the backhoe off in the middle of the night in the dark.

Gasoline gensets are not (generally) as durable as diesel.

That is an excellent observation. OTOH, how much durability is required? I can reasonably forsee a total maximum of 500 hours the first year, and then maybe 100 hours per year after that.

If the engine lasts 2000 hours, that would be 16 years of service, and in all probability, 100 hours per year of power outages is a gross overestimate. 10-20 hours might be more realistic.

What did you end up buying? Or are you still looking?

Another consideration is how much noise do generators make? I have one in the motorhome which is very quiet, but a replacement costs $5k for 4kW. And, no, it will not quite do the job -- only 120 volts, no 240. It would be really dumb to end up with one that kept me awake all night, even if it did save the freezer contents.
 
   / PTO generator vs. Stand Alone #4  
Hi curlydave,

We have an 1963 15kW Katolight generator rigged for LP gas at work we use to power some secondary buildings on my "to do" list this summer... needs new starter & some tuning... it has a PTO spline off the engine side so the tractor can power it if major need occurs... loud, air cooled, old technology on the engine... powerhead works fine...

Generators I've been around have always been incredibly loud, but they are 15kW plus... and never insulated for sound...

Typically the engine goes first on a LP or gas (and odds are diesel) powered generator... the engine adds a premium on the price per kW you'll pay for the generator, and requires maintenance regularly like any other engine.

Just the head requires little to none if routinely tested/used. If it's strictly emergency use that is not needed instantly, you can get many more kW for a fraction of the price buying just the head... of course you can always convert your powered to PTO after the motor goes down the road.

But if the cost is not prohibitive & you enjoy annual maintenance, get one with an engine, use it routinely, and it may last beyound your days... like anything, just make sure it's used at least weekly so it doesn't dry out on you when your big jobs are done.

Good luck on the project!
 
   / PTO generator vs. Stand Alone #5  
Yes, you do have to take the backhoe off to use the PTO. There is a micro switch activated by the frame of the backhoe that prevents you from moving the rock-shaft or using the PTO.

While I only have a small Honda gen for my personal use, I would really like a propane automatic standby generator. I just do not have the need/resources for a large gen set.

Things that I think about propane gen sets

Only have to check the tank occasionally to insure adequate fuel supply. Most gas gen sets to not come with a big enough tank. I don't want to be outside filling the darn thing at 0 dark 30.

Also gasoline motors always seem to have "wet" ignition systems when I want to use them. (just my own bad luck, I'm sure)

I know that propane systems also use ignition systems, but tend not to "flood" like a gas job.

If a diesel gen set is used & a large supply tank is plumbed to it, the tank must be above the level of the gen set, & I worry about the small line gelling up in the cold weather (again, probably just my luck)

Also, I personally have had propane engines apart (from a bread delivery company, panel trucks used in regular deliveries) & the engines were as clean inside as the day they were new.

BTW, the engines were torn down because of head gasket problems due to no maintenance. The owner figured/forgot to replace the antifreeze occasionally & it was acidic, causing head gasket failure.
 
   / PTO generator vs. Stand Alone #6  
Your well is 240 right? Also a 5HP = 3730 watts but a pump motor will have quite a surge to it at startup. Is the 5HP the input requirement or the output rating? If output rating then I would assume an efficiency loss in there too. The pump is your biggest load and I really think a 4000 watt generator isn't enough. I would be looking at the 6000 continuous area.

For 500$ I bought a gasoline coleman contractor style generator with 5500 continuous/6850 peak rating. I have put probably 100 hours on it in the last couple of years. This winter we had a three day power outage it was 18 degrees and we had a windstorm. I got home after dark on the first day and the house with my baby girls in it was down to 60 degrees. No problemo, I'll pull out the genny. Well I couldn't start it and quickly grew tired of pulling the rope to spin the 11HP engine with cold 15-50 oil. I pulled the plug, it had a spark and was wet with fuel. I held my finger over the hole and pulled the rope, good compression. All of this took about an hour and was done with an LED headlamp in the howling wind and cold. I resolved to take the carb bowl off and dump it. There must have been water or bad gas in the bowl since it started right up after reassembly. My point is that a gas engine works very well, consumes about 3/4 gallon per hour, and is cheap but it must be used. I have been told that 90% of generator problems are from lack of use.

I now run it once a month with an electrical load.

Another benefit of the cheap, loud, gas generators is that they are mobile. I roll mine into the piuckup and use it to run my welder. Try moving a water cooled diesel genny.

500$
 
   / PTO generator vs. Stand Alone #7  
I'll pretty much second everything Highbeam said. Heck, I think I even have the same generator!!!

One thing I'd add is to avoid the Tekumush engine,or whatever it's called. Mine is a Briggs, which is ok. Honda is probably better, but as long as it's not mush, you'll be fine.

I like mine for the protable aspect of it. I can move it anyplace I need it and even leave it there over a period of time and do other things.

The PTO generator severly limits what you can do when your running it.

One particular bad storm that we had came out of nowhere. Steph had parked her car on the dirt close to where we were working. It rained so hard that she was totally stuck almost instantly. I pulled her out with the tractor.

When Hurricane Rita hit, the carpet guys were here and for some reason they drove off my gravel drive and got stuck. Again, I was able to pull them out with my tractor.

I'm not saying you will have people getting stuck all the time like I do, but having the ability to use your tractor and your generator seperatley if you need to might be a very nice advantage.

As for noise, why not run a pipe that goes outside and put a car muffler on it? Or you can store it under an exterior lean to like I do so the sound is very minimal. I also keep five gallos of fuel close by that I use on other things. This way it's always fresh gasoline in case i really need it.

Eddie
 
   / PTO generator vs. Stand Alone #8  
Dave,
Personally, I would not use a PTO driven generator for what you want. There are just too many other things to do with the tractor, and your backhoe problem is another. Home Depot sells a lot of stand alone back-up generators, one I'm looking at for my solar back-up sysytem. However, I would also agree with everything Highbeam said. I think you'll need at least 5k to run the pump. I had a smaller Coleman 3500w but no 240v on it so I bought a Generac Wheelhouse 5550 continuous with 8550 surge. It has been great and very quiet....more so than the Coleman even. I use it to run the well pump and do all my arcwelding at the property. It's got lots of power and is portable.

Here's a link to one, but you can get them at Home Depot too. Gnerac Wheelhouse 5550
 
   / PTO generator vs. Stand Alone #9  
I pondered that question about a year ago. I had an old Sears AC buzz box welder on its last legs, and a 5KW 6250 surge generator that wouldn't quite run my whole house including with the A/C on. I thought of buying separately a PTO generator and a new welder but did not.
My reasons being:
1) Didn't want to tie up tractor just to run a generator.
2) Didn't want to have to remove whatever implement was on the tractor PTO to hook up a generator.
3) Needed a new welder and wanted an AC/DC welder instead of just AC.
4) Needed a generator capable of running the whole house with the A/C on for those 85-90 deg. days when our power seems to go out the most often.

I sold my 5 KW gen. to my neighbor so he could run his house for $300 and wired him up to use it. (He didn't care about having the A/C on) and I bought a Miller Bobcat 250 NT AC/DC welder / 10KW generator with 19 hrs. on it that was factory reconditioned and came with one year warranty.
I left it on the shipping crate and mounted 8" wheels on for portability. Now I can load it onto my truck or trailer with my loader and take it to whatever job I need to do. and have backup power to run the house when needed.

Counting what I got from the neighbor and the price I paid for the recond. unit. it was cheaper than buying them separately.

Just my 2 cents.
 
   / PTO generator vs. Stand Alone
  • Thread Starter
#10  
Your well is 240 right?

Actually, the well is 720' right this minute and still drilling.

Evidently I picked a poor location.

The driller, who also supplies pumps, claims that a 5 hp pump will work down to about 1100 feet.

We have 6 gpm right now, and will stop at either 900 feet or 10 gpm. Somehow I have a suspicion that 900 feet will come first.
 
 
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