[FoodPlotter]

Hi,

Has anyone "done the math" on the benefits of a PTO generator versus a stand alone generator? I can get a small PTO generator (15hp/540rpm/7200 watts) from northern tool for $829. A stand alone diesel generator is $1300. Diesel is kinda required due to the lack of durability I've seen in commercial gas units. Thanks!

 

[KHodges]

What are the chances that you'll need your tractor for something else while you're out of electricity or otherwise needing the generator? if you're planning to use it as a backup power source during snowstorms, etc, will you need the tractor to move snow, or haul pieces of downed trees, etc?

The stand-alone would be my choice, the extra $500 is worth keeping the tractor free for other things. You can always put the generator on a small trailer to keep it portable. And you're correct about going with diesel. They are designed for long spells of constant rpm running, and will be more economical, fuel-wise.

 

[wayne440]

I have both- each has good points and bad.

PTO sets

(the good parts) You won't spend as much money. If your tractor doesn't run, you can probably find one that does easily. You can buy a bigger generator than your tractor will "pull" at full load and have bunches of power available for starting things like well pumps. Your neighbors who don't own tractors won't be asking to use it. Your fuel is always reasonably fresh if you use the tractor for other things.

(the bad) A tractor in stationary use needs someone to watch it, lose a radiator hose, belt or so on while you are inside taking a shower and the engine will often run to destruction. Your tractor can't be used for anything else while you are making power. Takes a few minutes to hook up the generator to the tractor.

Diesel generators

(the good) A quality diesel generator will usually give better frequency and voltage regulation than your tractor can on a PTO set. You can use the tractor for other work while you make power. Many generators have low oil pressure, high water temperature, etc. shutdowns. Your radiator hose can still go bad, but the engine may not be badly damaged.

(the bad) A good generator costs a lot of $$$, I bought a 25 year old used Onan and it cost well over twice the price you quoted. If it is easily portable your neighbors will ask to borrow it. Most are eventually forgotten until some emergency comes along, and are then full of stale fuel and water. Another engine to maintain- oil change every year, coolant flush every 5 or so, battery replacement and so on.

Commentary

Some people see the words diesel and generator together and forget that all "diesel generators" are not the same-quality costs money. The Chinese knock off you buy for a cheap price is not what a Cummins/Onan or Kohler set will be. After 1000 hours one is broke in, the other is broke down. If you must choose between a "cheap" diesel set and a PTO generator, you will probably be better served by a PTO set.

Disclaimer-I'm not looking to argue these points. They are based on my 20 or so years of experience with making electricity in the aftermath of various emergencies. I'll glady listen to other views, but they are unlikely to change my opinion.

W

 

[davidg]

i agree with wayne, buy a quality unit that fits your specific needs. it is better to go a size to two larger than you need for future tasks. check out the maintenance requirements of the unit before you buy it, the cheaper the unit the more it will require to stay running.

jeez, that sounds like tractor buying advice!

 

[DJ in WV]

Very nice outline Wayne. Points well covered and taken. I agree 100%.

Nice disclaimer too.

 

[x595]

Hi,

Has anyone "done the math" on the benefits of a PTO generator versus a stand alone generator? I can get a small PTO generator (15hp/540rpm/7200 watts) from northern tool for $829. A stand alone diesel generator is $1300. Diesel is kinda required due to the lack of durability I've seen in commercial gas units. Thanks!

Hi FoodPlotter ,

The PTO and stand alone Generators in your quote will not run the whole
house , are you wanting to supply just priority needs or do you want a whole
house feeder ???

When I got mine , I was looking for a Diesel stand alone , but the selection
was limited for a whole house feed ... The one I decided on was from
Northern Tool , it's the NorthStar 15,000 Watt unit , it's a gasser
(25 hp. Kohler) , 120/240 v-60 Amp 6% or less (THD) and it will run the
whole house guaranteed , I'm very happy with it ... Sorry for the long post ...

Later,x595

 

[FoodPlotter]

I don't need to power the house. I just need enough juice to run the circulator pump on my boiler should the power go out in the winter. the boiler is hand fed, coal & wood fired. but if the pump is out, we're cold. thanks.

 

[x595]

I don't need to power the house. I just need enough juice to run the circulator pump on my boiler should the power go out in the winter. the boiler is hand fed, coal & wood fired. but if the pump is out, we're cold. thanks.

Gotcha :fing32: ...

Later,x595

 

[JDBrian]

Hi

I have struggled with the same choices. I am leaning towards a stand alone unit but there are a lot of crappy generators out there. I would like to go diesel but the cost is higher. For backup use you don't need to buy a commercial quality gen set but you need a quality portable unit that is reliable and serviceable ie: designed for continuous operation for short periods(a few days at a time) and parts that are available.
You need to maintain a backup unit or you will run into problems. You also should have some spare parts available and of course fuel and consumables like motor oil, filters etc.
I am getting by with an old 3kw generator that I have maintained properly. It has never let me down but I need a larger unit to start my well pump.
Keep an eye open for used PTO units. You can sometimes get a good deal on a used one.

Cheers
Brian

 

[wayne440]

FWIW, here are a few lessons learned during the Jan/Feb 2009 KY ice storm.

(1) "Cheap" (not inexpensive) Chinese import generators run about 24-48 hours before the rod ventilates the engine block, even with the best of care.

(1A) A $300 generator costs $700 when the lights are off.

(2) When Briggs and Stratton says "check oil at every fill up" they mean "this engine is going to use some oil, keep it full or lose it".

(3) The decal that says "change oil every XX hours" probably has fine print that says "... or this engine will fail." It will.

(4) When you check the oil on a Generac air cooled set, screw the cap in then out before reading it. If you don't it will be too full, and the crankcase seal(s) will fail, either at the crankshaft, governor shaft or both in about 6 hours.

(5) Whatever fuel your generator runs on will be unavailable or in short supply. My 30 gallons looked like a lot sitting there in cans, but didn't look like much when I was burning it to make the lights work. (I now have a 150 gallon tank)

(6) A good rule of thumb to estimate how long your generator will last is how much oil it needs to bring the dipstick from "add" to "full". If you add "ounces", expect to have trouble in 48-96 hours. If it takes "a quart", you are probably good for 7-10 days or more. If your engine is one of the few that requires a "gallon" (such as the 2-71 Detroit, 4B Cummins etc.), it may very well run for as long as you have fuel and oil to feed it.

My standard disclaimer applies...LOL

W

 

[Team_Green]

Wayne.. Good insight...

 

[BLIND REF]

Wayne.. Good insight...

:ditto: :ditto:

 

[Kbeitz]

Hi FoodPlotter ,

The PTO and stand alone Generators in your quote will not run the whole
house , are you wanting to supply just priority needs or do you want a whole
house feeder ???

When I got mine , I was looking for a Diesel stand alone , but the selection
was limited for a whole house feed ... The one I decided on was from
Northern Tool , it's the NorthStar 15,000 Watt unit , it's a gasser
(25 hp. Kohler) , 120/240 v-60 Amp 6% or less (THD) and it will run the
whole house guaranteed , I'm very happy with it ... Sorry for the long post ...



Later,x595

I disagree... Everyones home is different..
I power my home (Everything) with a 5 kw genset...

 

[x595]

I disagree... Everyones home is different..
I power my home (Everything) with a 5 kw genset...]

Hi Kbeitz ,

Your right every home is different , but they would'nt run mine ...
IMO anything under 10,000 WATT (which also depends on the Generators
AMP output) would not start my 3 TON heat pump A/C compressor and I say
that because , when it starts up my 15,000 WATT Generator whines down
then throttles up , that would shut down anything under 10,000 WATTS ...

Later,x595

 

[danbike]

When we had the house built, it was our first with a well and septic. One flush when the power goes out was not something we wanted to consider.

So, we had a 12 KWH Generac built into the electric system with a sub panel for everything necessary. The Generac burns natural gas and has an automatic startup system. We have our well, lift station, basement ejector pump, sump pump, basement , furnace, kitchen, and master bedroom on the subpanel.

I know that this is probably overkill. Our old house was in a town that has 6-8 hour blackouts every month. In the four years we have been here, we have only needed it once last winter. Felt good to have heat. Just for the record, our AC is not on the backup. That would have required a much larger(expensive) system.

 

[wayne440]

...

(7) Whatever appliance your generator won't run will be the one your spouse just has to use, "right now". :banghead3

My first "standby" set was 3.5kw, but it wouldn't satisfy rule #7.

25kw is about right.

 

[JDBrian]

Hi

My biggest load for a generator is the well pump. It takes a 4 to 5kw generator to start the pump. If I could find a small diesel setup that would be ideal. Something around 7-10kw but they almost never come on the market used. A gas set in the 10kw range just burns too much fuel when lightly loaded which is mostly what it would be doing with brief peaks for starting the pump etc. A diesel would be much easier on fuel in that scenario.

Brian

 

[Mark in Portugal]

I have a 3.5kw Victron inverter, with 7kw surge capacity.
I've just rewired the whole house, and what I did was put 2 circuits to each room; outlets are in pairs, side by side [normal configuration here]. Each right socket is connected to the backup circuit [on phase 1 in my distribution box], the left outlets are not [and connected to phase 2 or 3]
Phase 1 will be diverted through the inverter, with it's automatic switching relay and time delay reset.

Heavy users, like oven, washing machine, dryer, toaster, are on phases 2 or 3, not backed up [stove is gas, heat is oil until I build the solar].

I had the same setup when I lived in India, and it's ideal for short outages that happen often.
Although we're in a fairly wealthy seaside tourist area, the power starts to go on the blink when the rains start in the fall; saline build up on the insulators it seems.

Advantages; automatic, silent, fuel free.
neighbors go batty when your lights stay on and everything else is off.

Disadvantages; you still need a generator for when the blackout exceeds your battery capacity.
Batteries need replacing after 5-10 years, and are expensive [over here, $300ish for 2x120AH]

 

[JDBrian]

Hi folks

I got a used PTO generator. See this thread.
http://www.mytractorforum.com/showthread.php?p=755884#post755884

Cheers
Brian