2 1/2; 5 1/2; 7.0; 10.5 &18 Horsepowers

Hi All,
Cloudy rainy day here so I have time to lay-out my actual tree-farm used power needs.
These are all of my seasonally farm-needs, used, different power equipment’s that I use annualy.

To refresh: I and my wife live on 18 acres of a once120 acres old dairy farm remains. We retained the 15 acres treed section. With an additional 3 acres lots with two houses and some outbuildings, small old hay field, dog fenced yards, fruit&shade trees, and the gardens plots.
So . . . could we actually make on-site with just the sun and rains falling on our properties the energies to live on this small of land area remains?
With wood heating’s.
With wood-for-energy for these shaft power needs.
With woodgas for electrical uses for refrigeration’s, well-water pumping and lighting/entertainments.

So If You are an Urban/Suburban living: DO NOT READ, and follow this topic.
You cannot on those small of, lands footprints, site-grow the wood fuels needed.
This IS put on the Woodgas FARMING section intentionally for those who have already made the lifestyle choices, where, and how to live so that they could.
tree-farmer Steve unruh


I know to use horsepower for shaft work/energy measurements is archaic.
Not using the current modern convention of kW/mechanical keep the “figurer’s” types, from gaming this topics contents.

Now that horse; or mule, or bull-ox; or human slaved could only produce usable power for relatively limited short periods of time daily; with relatively huge daily base-energy input needs.
Easy to look up the land areas needed to annual quality fodder raise for the four legged power sources. Or . . . go look over current Amish farms.
Human energy input for daily/annual food energy input needs versus applicable work/power that can be applied?
Bicyclists. I was a modern do-all-bicyclist from the mid-1960’s thru the mid 1980’s. Ha! Great books and studies made then of per-person best systems applicable that were possible. Nothing changed even with recumbents.
1/10 horsepower per hour for most; to a young person WELL conditioned 1/3 horsepower per hour is/was the best.
So . . . ~2500 base-line calories a day to be able to per hour (with the necessary foodsinputs) to be able to produce at best a usable 250-400 calories of work achieved per hour. And only a fifteen year old thru maybe 55 year old could do this for a majority of maintained daylight hours. So, yep take you 15 years of support inputs to start getting usable work out of a human. Lot of no/low outputs years/energy inputs expended to get to that point. Trashes your life-cycle efficiency numbers.
Those four legged power makers even worse on the full life-cycles years cumulative baseline foods energy inputs.
NOT working you still must grow/supply the food year around; idling, waiting to be worked.

My IC engine work producers eat nothing sat aside waiting for needful work.
Jeff Davis here on the DOW has put up some of the best works on wood-for-powering small engines. Also KoenV.L. Also Christian in Slovenia. Also Gary Gilmore. And others.

Ha! Even when I am using the 1994 Ford 5.0L V-8 pick up to trundle cut/split firewood from one end of our property to the other I am only actually using at most 18 horsepower.

More later if there is an interest. Have to clear off this public computer for now
tree-farmer Steve unruh


Great topic Steve, I’m looking forward to more.

As for figures for draft animals, I’ve read roughly 1/3 of crop land had to be devoted to pasture, hay, and grain feed.

One horsepower is equivalent to 750 watts, but as you point out, that’s only the tip of the iceberg in figuring real muscle power output.

For a sustainable future, I feel that syngas, biomass fueled shaft power is the only possible salvation. So the crop waste, or woodlot powers the working of the land, and other necessary power applications.

A syngas powered tractor with a pto generator could run a welder, and any heavy duty power application. Hard to get oxen to weld steel, no matter how determined… :slight_smile:

Syngas, and mechanization should actually turn out to be more energy efficient, and sustainable than horse farming ever was.

But to get there, we should be building small tractors like locomotives used to be designed, with a century design life. Fortunately the old tractors weren’t far off that design mark.

I see this as a road to permaculture, where we are going to have to go.


Yes I agree on the last-for-generations wood-powered tractor GarryT.
4-5 here on the DOW now doing this: David Baillie, Ron Lemler, Wayne Kieth, Arvid Oldson and BillS. And one more fellow . . . did a charcoaled pellet tractor conversion? Damn tricky failing memory!
I have sadly only a JD/Yanmar 3 cylinder 22hp diesel tractor left here.
Swedish Johan Lindell did woodgas convert his 3 cylinder diesel David brown tractor for farm and forestry working.

I have had/tried smaller 1 and 1 1/2 horsepower outdoor equipment’s. Too light weight incapable
and slow, slow.
True seasonal growing farming, larger scale gardening, forestry it becomes jamming achieved works into narrow seasonal growth/weather windows. NOT about killowatt efficiency-maniac minimizing bragging.
Your goal is to take care of you and yours. Not provide solutions to 40-60 million Urban/Suburban “my-house-as-my-ATM-living” style households. Most of my blood relatives are these.

Ha! I had to rocks dig in five replacement wooden post fence hole this Spring. By hand with a shovel and a rock bar got the jobs done. Neighbor did the same with his four cylinder diesel Kubota and a 12" PTO auger. (he had to relocated many of his holes due to too big of rocks. And he will be still making payments on that 3 year old, bought new Kubota for another 9 years.)

Sometime human sweat is the best way to go. Keeps you younger, healthy, wealthier and wise. Still no overhanging gut on this old bicyclist.

tree-farmer Steve unruh


Hello Steve.
I agree totally with your 1/10th HP from the human. Back in the '70’s, when I was about 40, I built a battery charging bicycle that I called my “Genebike”. Simply a car alternator being friction driven from the bike’s (front, in my case) wheel. I hooked up a rheostat to control field current and a couple of meters. That way I could find the sweet spot for human peddling rate vs comfort and endurance. I got 1/10 HP too. I figured that “sustained” meant about one hour at a time.
I built it for some “hippie” off grid friends who had an old Jacobs wind turbine that was in a hollow that didn’t get much wind. I had given them a set of deep cycle batteries. They had two kids. That way, they could, if they wanted, put some juice into their system when the wind didn’t blow. In a light hearted way, I told the parents that, whenever a kid misbehaved, he could be punished by saying: “Okay, kid, Give me a kilowatt!”
I think that 1/10 hp translated into about 8 tablespoons of gasoline. After that, I felt that a chain saw was a proper use for petroleum.

Pete Stanaitis


Amen for chainsaws…


“Chainsaws” Yeah! I just today got the three rubber elastic anti-vibe motor mount to be able to put my old-man easiest to use 2.3 horsepower “old” now Stihl 260 Pro back into use.
Got a new semi-chisel skip-tooth chain, new bar, new sprocket to now work up the big left behind 40’ to 56" butt cutoffs and high stump shortenings too with my now “old” 5.5 horsepower Stihl 440 saw. The 34 ton force hydraulic woodsplitter to reduce these twisted grains rounds runs happy on a 2800 RPM throttled back 10.5 horsepower cast iron liner B&S.
Chainsawing is all about chain speeds. The power to keep the chainspeeds up, cutting(cooling) and chips ejecting.
60 year and forward modern chainsaws ARE all about spec grades of gasoline’s. And lubricants.
Not really woodgas power easily compatible made using a saw chain system. My wood splitter . . easy to woodgas as Gary Gilmore has demonstrated.

So . . . woodgas powered . . . use a slower/larger four-stroke IC engine speed band saw or drag saw system.
Not as easy/portable as a 70 year evolved highly refined gasoline powered major manufacture chain saw system. But these others CAN be artifice’d down to one-man sawing operations.
Go look at a drag saw historic demonstration. Imagineer dumping out of the old cranking cast iron gasoline engine into a cast aluminum OHV modern four cycle engine. Imagineer having most of the brass bronze moving action bearings as ball bearing types. Only takes at most 2 1/2 horsepower. Some metal cutoff saw already set up this way - electric motor driven. Engine re-power.
Band-type: Imagineer a deep throat-ed fixture sideways for 16" cutoffs IC woodgas fueled engine driven. Take ~5.5 horsepower. Again a fairly common metal cutoff set up configuration - electric motor driven. Engine re-power.

So in stand-alone farm/Rural going back wye-in-the road mistake taken? US/Canada 1930’s in “refining” the original consept single and dual cylinder engine to ONLY operate on supplied/canned dino-fuels. Far, far away from the original concepts of rural/farm made fuel alcohols or even older site-made (wood)producer gases.
Only for a short needs-must war years European time period was the small farms refined fuel dependencies gone back to farms-made fuels.

We can individually create our own back-to-the-futures by going back to insisting individually only using site made fuels and modifying the work-makers-cycles that will only work with out sun-made fuels.

The Investor/Designers/“wealth-makers” Priests-of-Needs will always keep you dependent on their consumable must-have, must-use glittery, shinier products and services.

Be the smart old crafty fish. Refuse the baits. Hooked - throw the hooks. Heal up and be wiser thereon going forward.
tree-farmer Steve unruh


Hmmm, According to Roger Rainville up in Alburgh, Vermont. About 20% of his land (dairy farm) is used to grow sunflowers to make biodiesel. He says 20% was about what the horses used to eat.
But to me that’s beside the point. I KNOW how things work on a Vermont dairy farm. The trees have to be cut back all the time or the farmer will loose his fields in a few years. Tons and tons of wood are left to rot in the hedge rows up there. Soooo… I guesse all that rotting wood isn’t bad for the land. But what about the farmer? What if he could get just a little something back for all the hard work he does keeping his fields clear. I suspect Roger Rainville could cut wood in the winter and use ALL his tillable acres to grow food for his cows. The only chink I can think of in my argument is that Roger feeds the meal from his sun floweres to his cows, after he extracts the oil. So really a little les than 20% of his land is used for fuel production. Of course everything comes down to economics, and I don’t actually know where Roger would come out at the end of the year if he did it differently.

Oh Ho, You might be surprised at how quickly some of those old timers would come up with a method for making something like that happen. I happen to remember a rig somone had put together to make shaft power for a hay baler. He used an old truck rear end flipped over so the drive shaft connection became a PTO. Snow chains on the tires. Simple!!! He had also built a ‘doodle bug’ shortened the frame on an truck to make a kind of tractor. This way he could fill up two hay racks with 60lb bales, hook them toether, and pull them back to the barn to be unloaded. This gave him a road speed of about forty miles an hour, and so saved time. As Wayne would say poor folks have poor ways.


Exactly my point, solar energy contained in woody biomass, exploited in a tractor or other machinery that uses no energy, and takes up no pasture, or care when idle, should allow greater production than traditional practices. What IC power was such a godsend for originally.

I’ve examined the old time fixes people used to do, riveting, bolting, and blacksmithing stuff together. I would be very sad if arc welding wasn’t part of the picture. :slight_smile:


I hate to be the devils advocate, but this line of reasoning made my curious… If you were to add up all the food energy that is “wasted” on keeping an animal alive when you are not working it, and compared that total to the amount of energy needed to extract ores, smelt metals, refine, machine, ship, paint, market, deliver, service, and every other conceivable off-farm input needed to get a functioning tractor to your doorstep - which one wins?

Once the tractor is there, I absolutely agree that it is the more “efficient,” but put 2 tractors together in a field and see if they make you another one by next spring :wink:!

Its tempting to think that there was some perfect era in the past, when things were simple and wholesome, and if we could only get back there all our troubles would cease. I dont know, it sounds nice… but maybe too good to be true.


I actually had one of those extension fliers from the 80s, that said you could supply your own energy needs with 5 acres of poplar in a rotation using coppicing. I don’t think that included transportation. I have always been intrigued by that, but I never got poplar to clone and actually grow except once with my dad… (part of that is most likely bunnies and deer), I am not paying money for rootstock when you need a couple thousand. :slight_smile:


Or maybe life in the past was just “solitary, poor, nasty, brutish, and short” as Thomas Hobbes said. Back in the day, just before cars and tractors came on the scene, gasoline was thought to be a useless byproduct of kerosene making and was used to get rid of lice. http://mentalfloss.com/article/57983/9-terrifying-medical-treatments-1900-and-their-safer-modern-versions
Maybe the perfect era is in the future. But if it does happen I think we will find it very odd, becuse we are imperfect people.


I’ve found poplar to be amongst the easiest things to grow/ clone, just take a fall or spring branch cutting about as thick as a finger 10" long, trench in the ground, as long as sticks are planted well before budding, success is very high. Willow is just the same. Coppicing I can’t claim personal knowledge, but it seems like a very viable system.

Could 5 acres address all modern needs? Good question. Is it the right question to ask if a permaculture system should be made to resemble the golden century of fossil fuels?

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Here’s where things get complex.

Very true, to extract iron from ore, manufacture and process is hellishly energy intensive. European nations used to devote all their free charcoal to smithing and ore refining and casting. But recycling existing iron is on a different energy level.

In my opinion, corporatism skews the field, planned obsolescence, when we could easily be designing and building for a century useful machine life. Older tractors are not far off that mark, back when engineers and machinists were proud, and free to build as well as materials and technology would allow.

If we were building century grade equipment, or even half that, I’m sure the increased efficiency and productivity falls strongly in favour of syngas powerd IC.


This is very interesting. Here is the part where the whole horse versus tractor part falls apart for me. I hear the whole horses reproduce argument a lot. Yes the tractor wears out and needs parts and cost energy to make but people always equal one team of horses to one tractor. My point is if you only did the work of one team of horses with that tractor how long would it last? I would say nor far off that century mark. Since I have one that runs fine and is 65 years old I would say it has earned it’s resources and out produced many teams…


And the iron of that immortal team can be recycled / rebuilt into other century teams, no pasture required…

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Hi Steve, my experience with horses is extensive; 40 years ago when I started farming I had an old IH tractor that broke down, at that time could not afford to fix. I was thankful I had 2 teams of horses, and equipment. With out that I couldn’t have done the farm work, pulled fire wood, and timber. With that said, I had plenty of hay, and pasture to feed them.


Alright, I was curious, so i crunched some numbers… I found an exhaustive energy accounting for the production of a car - which probably uses more energy than a basic tractor, but bear with me. you can read about it here https://greet.es.anl.gov/files/vehicle_and_components_manufacturing

The takeaway? The manufacture of a car (I want to say they used a 1500kg baseline for weight) used 34,000 MJ. I did not read the entire report, but I will go back and skim it later, as it is quite interesting.

Next, I looked up the energy needs of one horse and found this: http://www.dayvillesupply.com/hay-and-horse-feed/calorie-needs.html It claims you need to feed a horse 15-33k Calories a day. Lets assume you are working your horse hard one day, then letting it rest a day, and your average daily feed is 22,500 Calories.

So how far would 34GJ go to feeding a horse? If I did this right, I am coming up with something like 1 year, which surprised me. Considering that a 1500kg tractor would be in the 30-40 HP range, and assuming you designed a machine with at least a 50 year service life it seems the tractor is going to come out way ahead. Granted the machine has not been fueled in this scenario, and the horse has put in 180 days of work, but its not hard to see that the energy to keep a horse alive and not doing anything is quite high (~5.5 million calories 23 GJ) per year.

So- next question - how many acre/years of trees do you need to make 34 GJ of biofuel?


Very interesting numbers. They surprise me too, that the advantage would be that stark. There are nuances to the figuring, as the tractor manufacturing inputs are all industrial scale mining and processes, fueled by industrial fossil fuels, whereas the horse team is living on solar energy.

But even if we double the figure, or more, it seems the machinery is the clear winner, and especially if the tractor energy comes from non farm land biomass.

Makes those old gas tractors look more attractive…


I always try twigs, but the closest I have gotten was when I took cuttings in the winter. But I don’t use twigs that thick. So maybe that is the problem. Willow supposedly coppices easier.

It might have been like 7 acres to cover electric use. It didn’t cover transportation.

I don’t think it is necessary good to mimic current ff use or even what we did previously that we abandon. There are some things that are applicable but you have to pick and choose. But I’m not trying to do permaculture or organics either. I just use what I think can work easily.