PTO generator
- Thread starter Fredmeyer
- Start date
coachgeo
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L225 w/woods Few Mowers & Back Blade, D722 in Motorcycle (Triumph Tiger), LMTV
LOT of threads on this topic but I know its impossible to search by PTO so takes a lot of digging to find them. Below are a few good ones
http://www.orangetractortalks.com/forums/showthread.php?t=21378&highlight=Generator
http://www.orangetractortalks.com/forums/showthread.php?t=5737&highlight=PTO+Generator
http://www.orangetractortalks.com/forums/showthread.php?t=21378&highlight=Generator
http://www.orangetractortalks.com/forums/showthread.php?t=5737&highlight=PTO+Generator
Last edited:
North Idaho Wolfman
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L3450DT-GST, Woods FEL, B7100 HSD, FEL, 60" SB, 743 Bobcat with V2203, and more
Don't do it!
It's not efficient or effective!
Buy a generator that has it's own motor.
Here is another way to look at it:
The big storm blew in and knocked out power and downed several trees across the driveway.
The wife is yelling loudly and obsessively at you for power! She's got to get the news on the tell-e to find out if the bingo hall at church has survived the storm chaos and of course there is also the season finally of "As the stomach churns on channel 5", and she says it will kill her if the deviled eggs in the frig go bad... Dam-it man quit thinking the eggs killing her thing is good and get her power!
The whole while you could have saved yourself by using the tractor to clear out the downed trees across the driveway and making a subtle and hasty getaway to the local pub to have a candle lit beer with the buds!
Yes overly dramatic, but still valid, there is so many cases where tying up a tractor running a generator is a bad thing.
It's not efficient or effective!
Buy a generator that has it's own motor.
Here is another way to look at it:
The big storm blew in and knocked out power and downed several trees across the driveway.
The wife is yelling loudly and obsessively at you for power!
She's got to get the news on the tell-e to find out if the bingo hall at church has survived the storm chaos and of course there is also the season finally of "As the stomach churns on channel 5", and she says it will kill her if the deviled eggs in the frig go bad... Dam-it man quit thinking the eggs killing her thing is good and get her power! The whole while you could have saved yourself by using the tractor to clear out the downed trees across the driveway and making a subtle and hasty getaway to the local pub to have a candle lit beer with the buds!
Yes overly dramatic,
but still valid, there is so many cases where tying up a tractor running a generator is a bad thing.Don't do it!
It's not efficient or effective!
Buy a generator that has it's own motor.
Here is another way to look at it:
The big storm blew in and knocked out power and downed several trees across the driveway.
The wife is yelling loudly and obsessively at you for power!
The whole while you could have saved yourself by using the tractor to clear out the downed trees across the driveway and making a subtle and hasty getaway to the local pub to have a candle lit beer with the buds!
Yes overly dramatic,
I'm getting storage looks from the dog for laughing at this.
Sent from my iPad using Tapatalk
85Hokie
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BX-25D ,PTB. Under Armor, '90&'92-B7100HST's, '06 BX1850 FEL
Fred,
As you read the other posts, you'll see.....that the idea is very sound, but the practicality of the genny on the back is not a good one.
Your tractor is tied up like NIW points out ( I too was LMAO) and the cost of the PTO version is gonna be mucccchhh higher than a stand alone!
Now if somebody GAVE you one, or you picked up one at a crazy low price, sure I would give it a shot, but to buy a pto driven genny would not be money well spent.
You can find them everyday on CL and get a gasser for $250 or a new one for less than $500. The thing to do is use it once in a while, otherwise the ONE time you NEED it ....the gas in it will be bad and it will add insult to injury when it does not start!
As you read the other posts, you'll see.....that the idea is very sound, but the practicality of the genny on the back is not a good one.
Your tractor is tied up like NIW points out ( I too was LMAO) and the cost of the PTO version is gonna be mucccchhh higher than a stand alone!
Now if somebody GAVE you one, or you picked up one at a crazy low price, sure I would give it a shot, but to buy a pto driven genny would not be money well spent.
You can find them everyday on CL and get a gasser for $250 or a new one for less than $500. The thing to do is use it once in a while, otherwise the ONE time you NEED it ....the gas in it will be bad and it will add insult to injury when it does not start!
Grouse Feathers
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Lifetime Member
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BX2370, FEL, Snowblower-BX5455, Homebuilt Forks, LP RB1560, LP GS1548
In Vermont? When a snowstorm hits dropping a foot of wet heavy snow taking down trees and power lines, what becomes your priority? Power for the snowblower or power for the pump to flush the toilets? How fast can you switch back and forth between the snowblower and generator? If you have to go to work will you leave the tractor running for your family? Just a few thoughts.
When we were without power for 7 days my B7100 ran a pto generator about 16 hours a day. All the roads were closed and there was no power at any of the gas stations if you could carry a can there. I did have plenty of fuel oil in my shop which was easily siphoned. I think a stand alone generator is only as good as the amount of gasoline you store. A standalone generator must also be maintained or when you finally need it, it won't run.
Opinions vary so here we go, I have a pto generator 13KW and it takes 24 hp at max load. I agree it depends on where you live and what normally causes power outages. Where I live our problem that cause extended power outages more than a 2hrs are hurricanes. If we get snow today it is gone tomorrow. I also did not want another small engine to maintain. So it is what ever you want all have great points. Just be sure your pto hp of the tractor is capable of max load for the generator.
tcrote5516
New member
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BX1860, FEL, 50" Front Blower, Heated Cab, 6' blade, 3pt carry all, 3pt hitch
The only real advantage to a PTO gen is the ability to move it wherever you need power. For the 4th of July I setup a big fireworks show set to music out in a field about 500 feet from my house. I end up using a big 12v inverter to run the PA. Would love to find a PTO gen for a decent price to do it but no luck so far.
I have a gas 1KW generator for the house and the maintenance is minimal. Change oil once per year and drain/refill fuel tank once per year if it wasn't used enough to burn through it. Total investment is prob less than 1 hr and I'd spend more time setting up a PTO gen once then I do maintaining my permanently installed gas gen all year.
I have a gas 1KW generator for the house and the maintenance is minimal. Change oil once per year and drain/refill fuel tank once per year if it wasn't used enough to burn through it. Total investment is prob less than 1 hr and I'd spend more time setting up a PTO gen once then I do maintaining my permanently installed gas gen all year.
I used to see them all the time, (just looked and could not find one), will do a little more looking.
Not what I was looking for but you might be able to make something like these work.
http://stores.ebay.com/Generator-Store?_trksid=p2047675.l2563
http://stores.ebay.com/Generator-Store?_trksid=p2047675.l2563
I really, really debated on getting a pto generator, then talked myself out of it for 3 reasons.
1. As others stated, it ties your tractor up to possibly do other things.
2. We seem to lose power with extreme weather; super cold, freezing rain storm, blizzard, torientail rain supercell, etc. Without a cab, not really wanting to go out in those elements.
3. Wattage, will it run all my needs, including geo-thermal, multiple frig's...
Definitely wanted something since I'm 99% dependent on electricity, except for propane stove and a supplemental wood burning fireplace. I was more worried about heat and/or frozen pipes.
Went to a local home show, talked to a local Generac rep, eventaully came out to the house and ended up buying a whole house unit. Way more money than intended but so glad I went that route. It runs EVERYTHING, Ive checked. No more worries. Both of us work so it just runs as needed. On vacation, it runs. We have a camper and if gone, it runs.
After 1 year it has run 3 times for 9 hours, 2 hours and 37 hours.
1. As others stated, it ties your tractor up to possibly do other things.
2. We seem to lose power with extreme weather; super cold, freezing rain storm, blizzard, torientail rain supercell, etc. Without a cab, not really wanting to go out in those elements.
3. Wattage, will it run all my needs, including geo-thermal, multiple frig's...
Definitely wanted something since I'm 99% dependent on electricity, except for propane stove and a supplemental wood burning fireplace. I was more worried about heat and/or frozen pipes.
Went to a local home show, talked to a local Generac rep, eventaully came out to the house and ended up buying a whole house unit. Way more money than intended but so glad I went that route. It runs EVERYTHING, Ive checked. No more worries. Both of us work so it just runs as needed. On vacation, it runs. We have a camper and if gone, it runs.
After 1 year it has run 3 times for 9 hours, 2 hours and 37 hours.
My experience: you'll regret using a PTO driven generator.
Get a stand-alone engine-driven set as large as you can afford---then squeeze up to the next larger size.
Install a "whole house" transfer switch; stay away from those little 5 or 6 circuit add-on supplemental breaker boxes.
Power your stand-alone generator with propane. Invest in a minimum 250-gal tank, fill it, valve it off, and just let it sit until needed. Tee into your fuel line a 20-lb (approximately 5-gal) BBQ propane tank to use as a 'day tank' for test runs---15-minutes per week minimum. Running on 'liquid' propane instead of 'vapor' allows for longer runs of smaller diameter piping---this will be built into how the generator engine is set up at the factory or may be field-modified in some cases.
You don't need to be storing gasoline or diesel in sufficient quantities to keep you going if the grid dies in your area. Both liquid fuels go bad; propane doesn't. If you run out of gas / diesel, where would you go to get more and how would you get there and if they had any could they pump it?
Natural gas would work instead of propane but if the natgas distribution system floods or leaks (pretty common, just doesn't make the news), you're out of fuel. Propane tanks float; chain it to anchors or to slab if in wet area.
Please post back your continuing experiences so we may all learn.
Get a stand-alone engine-driven set as large as you can afford---then squeeze up to the next larger size.
Install a "whole house" transfer switch; stay away from those little 5 or 6 circuit add-on supplemental breaker boxes.
Power your stand-alone generator with propane. Invest in a minimum 250-gal tank, fill it, valve it off, and just let it sit until needed. Tee into your fuel line a 20-lb (approximately 5-gal) BBQ propane tank to use as a 'day tank' for test runs---15-minutes per week minimum. Running on 'liquid' propane instead of 'vapor' allows for longer runs of smaller diameter piping---this will be built into how the generator engine is set up at the factory or may be field-modified in some cases.
You don't need to be storing gasoline or diesel in sufficient quantities to keep you going if the grid dies in your area. Both liquid fuels go bad; propane doesn't. If you run out of gas / diesel, where would you go to get more and how would you get there and if they had any could they pump it?
Natural gas would work instead of propane but if the natgas distribution system floods or leaks (pretty common, just doesn't make the news), you're out of fuel. Propane tanks float; chain it to anchors or to slab if in wet area.
Please post back your continuing experiences so we may all learn.
I'll add a "+1" for the propane generator option. While whole-house Generac units running on natural gas or propane are certainly a viable option, the cost of such a solution is prohibitive for many people. If you don't mind dropping that kind of money, get one and be done with it.
For people dealing with tight budgets, portable emergency generators are the next best thing. I have a Yamaha EF3000iSEB inverter generator and it works great as long as it gets exercised regularly. Luckily, it has a rope start backup to the electric starter because I find that it usually has a dead battery by the time I get around to remembering that it needs to do a maintenance run. When the power is out, that dead battery and electric starter just add weight and makes the unit impossible for this old man to lift.
In spite of the significant cost difference between Honda or Yamaha inverter units and the noisy, cheap Chinese units from Harbor Frieght, I really believe that the Honda or Yamaha units are money well spent. My father has almost 3000 hrs on his Yamaha EF2000 and it still works like new. They are quiet enough that you can stand 5 feet away and carry on a normal conversation. That feature alone is enough to convince me, but they also make clean power that is safe for sensitive electronics. The cheap generators are notorious for making very dirty power with poor voltage regulation and lousy frequency management. They also run at full speed regardless of power output while the inverter systems can idle down for light loads and still make perfect power.
Converting to run on propane or natural gas means that even if the gasoline goes bad, you can still run the generator. Most conversion kits accept propane and methane fuel plus retain the original gasoline option so you have 3 fuel choices. For sizing a generator, bigger is NOT always better. Bigger motors are heavier and burn more fuel. As long as your generator can start the biggest electric motor you connect and the total connected load is under the rated continuous capacity, that's good enough. My 3000 watt unit loafs along at an idle when connected to the essentials during a power outage and it barely grunts when the refrigerator compressor kicks on. If I were buying one today, I'd go with the 2000 watt unit that doesn't have electric start and weighs half as much. The money saved by going with the smaller unit could easily buy the propane conversion kit.
For people dealing with tight budgets, portable emergency generators are the next best thing. I have a Yamaha EF3000iSEB inverter generator and it works great as long as it gets exercised regularly. Luckily, it has a rope start backup to the electric starter because I find that it usually has a dead battery by the time I get around to remembering that it needs to do a maintenance run. When the power is out, that dead battery and electric starter just add weight and makes the unit impossible for this old man to lift.
In spite of the significant cost difference between Honda or Yamaha inverter units and the noisy, cheap Chinese units from Harbor Frieght, I really believe that the Honda or Yamaha units are money well spent. My father has almost 3000 hrs on his Yamaha EF2000 and it still works like new. They are quiet enough that you can stand 5 feet away and carry on a normal conversation. That feature alone is enough to convince me, but they also make clean power that is safe for sensitive electronics. The cheap generators are notorious for making very dirty power with poor voltage regulation and lousy frequency management. They also run at full speed regardless of power output while the inverter systems can idle down for light loads and still make perfect power.
Converting to run on propane or natural gas means that even if the gasoline goes bad, you can still run the generator. Most conversion kits accept propane and methane fuel plus retain the original gasoline option so you have 3 fuel choices. For sizing a generator, bigger is NOT always better. Bigger motors are heavier and burn more fuel. As long as your generator can start the biggest electric motor you connect and the total connected load is under the rated continuous capacity, that's good enough. My 3000 watt unit loafs along at an idle when connected to the essentials during a power outage and it barely grunts when the refrigerator compressor kicks on. If I were buying one today, I'd go with the 2000 watt unit that doesn't have electric start and weighs half as much. The money saved by going with the smaller unit could easily buy the propane conversion kit.
+2 on the propane built in generator with whole house transfer switch. I have had mine for about 25 years now, a Dayton, and it has always run, exercises itself once a week, hooked up to the propane that runs my furnace. It doesn't run everything, and there are better available now. Ran for 15 hours Fri night. But I have heat, light, and well pump works. Got it after the power was out for 5 days between Xmas and New Years, hauling water for the stock in garbage cans in the back of the horse trailer, carrying it down the basement so it wouldn't freeze, carrying it back up by the bucketful got old really fast. I decided never again.
On the other hand I could see that a small pto powered generator that could be carried to the far North 40 to run power tools would be nice...
On the other hand I could see that a small pto powered generator that could be carried to the far North 40 to run power tools would be nice...
Grouse Feathers
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It can depend on where you live. My power is supplied by a small coop and I am at the end of the line. The last two big wind storms that took out power in this area resulted in 5 day outages. With a well for water and 20 miles to the nearest gas station, a propane whole house generator is the only way to go. If I am on a hunting or fishing trip my wife is all set if the power goes out for 8 hours or 8 days. Last winter we had an 8 hour power outage when it was -20 F. No way did I want to go out and hook up a portable generator or a PTO generator. When the power goes out my generator picks up the house in 20 seconds.
That is a very good point. Your circumstance makes the whole house unit sound like a great investment. For me, the last 16 years has resulted in a grand total of about 5 power outages that lasted more than 20 minutes and the longest of those was 4 hours. With that kind of record for reliability, I am just fine with a small portable unit that also provides juice for tools anywhere my pickup can go.
Back to the original point of this thread, I think a PTO generator has limited practicality. I'm sure they have a place in the world, but I have never wished that my generator was mounted to a tractor. If that day comes, I'll set my Yamaha on a 3pt platform.
It all depends, as many say. The most wattage you can get out of it is half t he engine horsepower. I've used one on a larger tractor and hooked a stand to the three point. Handy for powering stuff out there like tree trimming stuff. Our outages usually no more than one day. That was out in the woods.
Set the tractor in the garage and fed the power to the house in reverse of the regular use, BUT MADE SURE THE MAIN SWITCH WAS SHUT OFF. Mine is about 20 kw when run full bore.. Was handy to run my welder when I went to an Amish saw-mill where there was no power.
Now with the smallest BX I can run it, but won't get near the wattage out of it. However, 9 KW is still a bunch. For occasional outages this will do it, powering only some essentials. Where I live now, a city lot about 10 miles from the power plant so In 5 years have not had to run it. Reason I have it is that it would be handy maybe.
Set the tractor in the garage and fed the power to the house in reverse of the regular use, BUT MADE SURE THE MAIN SWITCH WAS SHUT OFF. Mine is about 20 kw when run full bore.. Was handy to run my welder when I went to an Amish saw-mill where there was no power.
Now with the smallest BX I can run it, but won't get near the wattage out of it. However, 9 KW is still a bunch. For occasional outages this will do it, powering only some essentials. Where I live now, a city lot about 10 miles from the power plant so In 5 years have not had to run it. Reason I have it is that it would be handy maybe.
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Continuing the conversation.
I'm pleased to see others are vocal about the benefits of propane and whole-house transfer switches.
We started the trend in our community and have helped about a two dozen others install all types standby gensets.
When talking with prospective owners about fuel storage we've learned to ask how they currently manage for lawnmowers and other small engines they own. Twice we've been shown a red plastic can in the garage closet next to the water heater.
The one greatest problem in owning a genset is fuel storage. Serious fuel storage. Enough fuel to run you for the next 3-days (FEMA's 72-hour policy of wait 'till help arrives) although we tend to argue for one solid week. Minimum. Which is where propane comes in.
We're literally at the rump-end of a ratty co-op line. Better now since the last ice storm took out more than 8,000 poles. We'll go on genset at least once a month, up to a day per episode. Ice storms? 27-days is our personal best. There was zero travel for the first week. Zero. The entire county was out for one solid week. Zero, zip, nada, nothing.
So where will fuel come from if you're not storing it? That's the question. Propane is the answer.
One poster posits that a genset can be too large. I differ. For practical discussions, an individual typically can't buy too large a generator, due to cost. Yes, a larger machine is inefficient in fuel use, but once the decision is made to install a genset, that argument goes out the window. Trade efficiency for convenience. Budget for the largest machine you can afford and then strain a bit and increase by one increment. We're talking about emergency conditions: fuel- and size-efficiency become secondary.
Too many times we've seen a household trying to make it on 3- to 5-Kw and then somebody forgets and flips the toaster while the microwave is running. There she goes: breakers trip.
Also for consideration is how your place is heated. Summer is hard but survivable. Winter can be tough. If you've got electric resistance heating or heat pump you need more power, lots more power. 'Emergency' heat on your heat pump supplemental strip heaters can easily use up 10-Kw. If you're on oil and you only need a pump and blower, different story.
If on waterwell using electric submersible, you don't want to go low-voltage due to domestic household loads and burn up the pump. That'll make a larger genset look cheap in comparison.
One poster, whom I greatly respect, describes backfeeding. Don't. Instead, install a whole-house transfer switch. Without the switch (auto or manual type) you get to continuously juggle extension cords either from the genset through a window or cracked door or dryer vent or from the six or eight receptacles energized by one of the little 'cracker box' supplemental breakers sold with smaller units. Pay the freight to get a whole-house transfer switch installed if you can't yourself and go the whole-house route for peace of mind.
It's described to flip breakers in order to accomplish backfeeding. First, don't. Second, the ONLY way to be CERTAIN the [back]feeding generator is isolated from the grid is (1) properly installed transfer switch or (2) remove the utility meter from its socket and cover the hole with plastic.
Concerning auto transfer switches. We keep ours on 'manual' and perform our own run-tests and switch-over. Had a house fire we responded to where an icestorm took out the weatherhead and the auto-switch didn't trip and the house burned while the aluminum siding was energized. Interesting event.
Consider the possibilities of a dual-purpose generator. This is something we've proposed for neighbors that want the security of a genset but struggle with the cost for a dedicated unit.
Go with a larger-capacity name brand engine-driven welder generator fitted for propane. The big name long-line machines are superb units and you can still find some models that have real copper windings. Or electronic-inverter type if that's your desire.
Our backup-to-the-backup puts out 12-Kw and only uses about 12-15-gallons per day. Coupled with a premium engine, these little guys are outstanding choices. And you can weld when the grid is behaving. And there is a huge resale market if you change your mind.
No matter what unit you choose, stock parts close at hand: filters (fuel, oil), oil, antifreeze, distilled water, belts, fuses, jumper cables, flashlights, anything expendable during a long run.
One more point: if your unit doesn't have an automatic battery maintainer installed, it should.
Comments suggestions thoughts ideas all invited; please post that we may all learn.
I'm pleased to see others are vocal about the benefits of propane and whole-house transfer switches.
We started the trend in our community and have helped about a two dozen others install all types standby gensets.
When talking with prospective owners about fuel storage we've learned to ask how they currently manage for lawnmowers and other small engines they own. Twice we've been shown a red plastic can in the garage closet next to the water heater.
The one greatest problem in owning a genset is fuel storage. Serious fuel storage. Enough fuel to run you for the next 3-days (FEMA's 72-hour policy of wait 'till help arrives) although we tend to argue for one solid week. Minimum. Which is where propane comes in.
We're literally at the rump-end of a ratty co-op line. Better now since the last ice storm took out more than 8,000 poles. We'll go on genset at least once a month, up to a day per episode. Ice storms? 27-days is our personal best. There was zero travel for the first week. Zero. The entire county was out for one solid week. Zero, zip, nada, nothing.
So where will fuel come from if you're not storing it? That's the question. Propane is the answer.
One poster posits that a genset can be too large. I differ. For practical discussions, an individual typically can't buy too large a generator, due to cost. Yes, a larger machine is inefficient in fuel use, but once the decision is made to install a genset, that argument goes out the window. Trade efficiency for convenience. Budget for the largest machine you can afford and then strain a bit and increase by one increment. We're talking about emergency conditions: fuel- and size-efficiency become secondary.
Too many times we've seen a household trying to make it on 3- to 5-Kw and then somebody forgets and flips the toaster while the microwave is running. There she goes: breakers trip.
Also for consideration is how your place is heated. Summer is hard but survivable. Winter can be tough. If you've got electric resistance heating or heat pump you need more power, lots more power. 'Emergency' heat on your heat pump supplemental strip heaters can easily use up 10-Kw. If you're on oil and you only need a pump and blower, different story.
If on waterwell using electric submersible, you don't want to go low-voltage due to domestic household loads and burn up the pump. That'll make a larger genset look cheap in comparison.
One poster, whom I greatly respect, describes backfeeding. Don't. Instead, install a whole-house transfer switch. Without the switch (auto or manual type) you get to continuously juggle extension cords either from the genset through a window or cracked door or dryer vent or from the six or eight receptacles energized by one of the little 'cracker box' supplemental breakers sold with smaller units. Pay the freight to get a whole-house transfer switch installed if you can't yourself and go the whole-house route for peace of mind.
It's described to flip breakers in order to accomplish backfeeding. First, don't. Second, the ONLY way to be CERTAIN the [back]feeding generator is isolated from the grid is (1) properly installed transfer switch or (2) remove the utility meter from its socket and cover the hole with plastic.
Concerning auto transfer switches. We keep ours on 'manual' and perform our own run-tests and switch-over. Had a house fire we responded to where an icestorm took out the weatherhead and the auto-switch didn't trip and the house burned while the aluminum siding was energized. Interesting event.
Consider the possibilities of a dual-purpose generator. This is something we've proposed for neighbors that want the security of a genset but struggle with the cost for a dedicated unit.
Go with a larger-capacity name brand engine-driven welder generator fitted for propane. The big name long-line machines are superb units and you can still find some models that have real copper windings. Or electronic-inverter type if that's your desire.
Our backup-to-the-backup puts out 12-Kw and only uses about 12-15-gallons per day. Coupled with a premium engine, these little guys are outstanding choices. And you can weld when the grid is behaving. And there is a huge resale market if you change your mind.
No matter what unit you choose, stock parts close at hand: filters (fuel, oil), oil, antifreeze, distilled water, belts, fuses, jumper cables, flashlights, anything expendable during a long run.
One more point: if your unit doesn't have an automatic battery maintainer installed, it should.
Comments suggestions thoughts ideas all invited; please post that we may all learn.
That was me, and I was only refering to choosing a small portable unit. I sincerely believe that small portable units should only be "just big enough" and no more. How big "big enough" is will vary for everyone and only you can answer that question for yourself.
For whole-house generators on a transfer switch, your advice is absolutely correct. A 500 or 1000 gallon propane tank will keep you going for a long time and you'll be happy to buy whatever quantity of propane is required to keep it going. For those who have a natural gas line to the standby generator, storage tanks are less critical but even natural gas supplies can go out for some of the same reasons that the power is out. It would be horribly disappointing to have your big standby generator sit quiet due to a natural gas outage. Having the ability to switch between NG and LP would be a prudent preparation. A quick Google search showed many options. Here's one just to illustrate the point: http://www.northerntool.com/shop/tools/product_200630886_200630886
Ideally, you would have a small, very efficient unit like a Honda EU2000 (optionally converted to run on propane) and a big, permanently mounted standby unit with a transfer switch. The big unit might stop running for one reason or another which means your little unit needs to be big enough to run the most critical loads while you work on getting the big unit back online. Having the little unit also means you can go mobile when the need arises. I wouldn't consider the big or small generator to be a substitute for the other any more than I would consider a drill press or a cordless drill to be a substitute for the other. They each have their place in the world.