electric tractor

questions for steve.

What is his favorite place to source parts he cant make and has to buy? motors, actuators, controllers, wiring, connectors, battries. Stuff like that. He must have a great source for a lot of these parts if he can build tractors as cheap as he mentioned in the previous series of podcasts.

As I get ready to make my first conversion, any tips or things to avoid that would save a guy some headaches?

Thanks for this series of podcasts Paul. I like this topic and appericate you taking your time to talk about it.

paul wheaton wrote: Standard tractors usually fill the big tires with a liquid that gives the tractor more weight.

Say again? Excuse me for asking but growing up on a farm, having worked on farms, and having family members who work in tractor repair I've never heard of or seen this practiced. We add weight to front of our equipment to keep the front end from "floating" while pulling a load or an implement. Weight over the rear wheels isn't typically a concern. How have you seen this practiced?

Heath Gilbert wrote:

paul wheaton wrote: Standard tractors usually fill the big tires with a liquid that gives the tractor more weight.

Say again? Excuse me for asking but growing up on a farm, having worked on farms, and having family members who work in tractor repair I've never heard of or seen this practiced. We add weight to front of our equipment to keep the front end from "floating" while pulling a load or an implement. Weight over the rear wheels isn't typically a concern. How have you seen this practiced?

Filling tractor tires with water was common practice on all of the dairy farms where I grew up. I suspect that where you grew up the land is flat but where I grew up the terrain is extremely "hilly" and tractor tires were filled with water.

I can vouch for that.

We managed to put a serious puncture in one of our tyres and took it into town to be mended. The guy took great delight in aiming the ensuing stream of water at the people sitting outside the cafe on the opposite side of the road. He got them, too!

Interesting! I assume that practice is old school and is no longer used on our modern machinery?

Heath Gilbert wrote:Interesting! I assume that practice is old school and is no longer used on our modern machinery?

Well I wouldn't assume that it is no longer used because there are still plenty of two wheel drive tractors being used on small farms. The development of 4 wheel drive tractors may have lessened the use of fluid filled tires but it will be a very long time before it disappears. I just called the local John Deere dealer service department and they still use fluid filling for tires if the farmer requests it. Lots of those old John Deere and Ford tractors around and still in use. I have always loved those old Ford 8N and 9N tractors.

Hey guys check out this guys tractor. He had the whole build on a forum, but I think the thread was expired or something.



I know the podcast talks about electric motors running best at about 2k rpm, most EV type motors I have seen run best at around 7k rpm. This guy burned his first motor up running at to low of an rpm. Does any one have more info on this?

I assume these electric tractors are limited to pulling? How long will an electric tractor pull an implement such as a plow or disc? I also assume it's unable to drive the PTO for a cycle mower or brush hog?

In the podcast we talk a lot about running stuff off a PTO.

Just wanted to comment upon last Electric Tractor podcast issue of $10k limit on Kickstarter products. There are ways to get creative with that, as others have done. Some suggestions are adding lesser levels of support funding options for CAD files or text files as rewards for $10 + support that collectively bring down avg price on 10 units at $9,900 per. If concerned for cost over runs of a few thousand make the tractor "base" model backing out batteries as example, then add back in with separate order for module, whatever makes up "X" thousand to make this work. Just a couple of suggestions vs giving up on this crowdfunding option.
Cheers Brian

Peter Hartman wrote:Hey guys check out this guys tractor. He had the whole build on a forum, but I think the thread was expired or something.

http://www.youtube.com/watch?v=3F9qmHY5YzQ&feature=g-like

I know the podcast talks about electric motors running best at about 2k rpm, most EV type motors I have seen run best at around 7k rpm. This guy burned his first motor up running at to low of an rpm. Does any one have more info on this?

The rpm range and efficiency varies by motor type and also design. Some motors can as was stated in the podcast creep along at only a few rpm and some motors are more efficient and run cooler at higher rpm. Whether it is AC or DC is also a factor. Generally speaking using DC motors best performance can be achieved at 90% of rated output. Heat is an important consideration. As the load increases on an electric motor causing it to slow down the amperage draw increases which also creates additional heat. Most of the motors big enough to power a tractor more than likely run most efficiently at around 185F or 85C. That may seem like a tremendous amount of heat and it is if no provisions have been made for ventilation. Magnets lose efficiency as they approach critical heat and different types of magnets have different heat tolerances. I have never built an electric vehicle but it has been something that has held my interest for a number of years. I am not sure if my babbling has been of any help but I might be able to answer some questions regarding various types of electric motors.

Just caught 174. I see, again, that sometime its harder to communicate what Im thinking, lol.. I assumed stepper motors were understood. Basically, a stepper motor is a DC motor with several coils and power is applied to one coil at time and the motor rotates just a little; so to get a single turn the power is pulsed in sequence to each coil. If, for example, you have a stepper with 4 coils and you pulse one coil the motor will turn 1/4 turn, pulsing the next wire moves the motor another 1/4 turn.. and so on until the motor makes a turn. These are the motor used in plotters and printers and many applications where control is important. They produce full tork at any speed from stopped to the greatest rpm. It seems to me that such a motor on each wheal would eliminate transmissions and gears increasing efficiency. I have not yet found any supplier for a large version of the motors.

Dave Bennett wrote:
The rpm range and efficiency varies by motor type and also design. Some motors can as was stated in the podcast creep along at only a few rpm and some motors are more efficient and run cooler at higher rpm. Whether it is AC or DC is also a factor. Generally speaking using DC motors best performance can be achieved at 90% of rated output. Heat is an important consideration. As the load increases on an electric motor causing it to slow down the amperage draw increases which also creates additional heat. Most of the motors big enough to power a tractor more than likely run most efficiently at around 185F or 85C. That may seem like a tremendous amount of heat and it is if no provisions have been made for ventilation. Magnets lose efficiency as they approach critical heat and different types of magnets have different heat tolerances. I have never built an electric vehicle but it has been something that has held my interest for a number of years. I am not sure if my babbling has been of any help but I might be able to answer some questions regarding various types of electric motors.

Alright Dave here is what I am thinking. There are quite a few old IH/Massey/Olivar tractors out there. Many are setting in fields and can be bought for a few hundred dollars. I thinks these would make excellent electric conversions. Most of these tractors that I have come across have functioning transmissions but the motor is locked up.

Here is an example that I have found locally here:
http://tractors.wikia.com/wiki/International_340

The gas engine is limited to 2000 rpm, and that is probably pretty close to peak hp. So looking at this motor:
http://www.go-ev.com/images/003_05_10_WarP_7_72V_SpreadSheet.jpg

It looks like the rpm is 50% higher or more.

What are your thoughts?

Steve said he'd converted some Porche Spyder kits to electric. Well, they now have a hybrid that gets 94 mpg and can go 200 mph.
http://www.theblaze.com/stories/guess-the-price-tag-for-this-porsche-supercar-that-boasts-94-miles-per-gallon/

Also, I am a rural mail carrier and a vehicle maintenance person told me the USPS ordered some electric delivery vehicles but after testing the first two, canceled the order. Why? They burnt up! It is very hard on any vehicle to stop and start about five hundred times or more in four hours. Imagine turning off and on any electric motors that many times even without a loaded vehicle it has to move. If Steve or anyone could convert one of those postal vehicles to electric that could work and not burn up then they might be able to get a sizeable contract.

I have a question on the tractor with the joystick for steering. I assuming it is using the drive wheels to change direction (different amounts of power change direction) but wouldn't that require a modification to the way the front wheels are mounted?

Check this out
http://www.builditsolar.com/Projects/Vehicles/GardenHelper/GardenHelper.htm

I recently acquired a joy stick controlled really heavy duty "off road" electric wheelchair. It was damaged in an automobile accident when my friend had it on his carrier on the read bumper of his pickup truck and was rear ended. Insurance bought him a new one so he gave me the damaged one. 2 DC motors, a joy stick controlled system that runs on 24 volts. I should be able to build a mini-tractor that will work well "in the woods." Christmas in July

Here's some photos of the electric tractor I built. It's frame is an Allis G, but that's about all that's left.

I built it using a 48V DC motor, eight 6V golf cart batteries, an Alltrax controller, and some other goodies.

Goodies:

* 2500W Power Inverter - powers two 110V AC outlets. Run anything from your tractor!
* E-PTOs - I used high-amperage bus bars used in marine applications mated to weather-protected Anderson connectors for true 'plug-in' PTOs. Implements are powered by another motor, not a PTO shaft
* USB ports - the tractor is wired for 12VDC, 48VDC, and 110VAC. Charging a cell phone is easy
* Stereo - line-in port to marine speakers. Weatherproof tunes for in the field. I run Pandora on my iPhone.
* Selective 'chop and drop' cultivation. Using the E-PTOs, I can mow down (chop and drop) between rows, rather than cultivate bare soil.

I'll post a video when I can, here's some pictures






Learn more:

electric tractor

Can you give us more information on how you geared that motor down with the belt and pulleys? Part#s would be great.

Peter Hartman wrote:Can you give us more information on how you geared that motor down with the belt and pulleys? Part#s would be great.

the motor plate was made by a machine shop. Add all the belts, pulleys, and machine work up and its around $600.

Niekamp Machine did the work. Though their quality is exceptional, their turnaround time and communication is terrible. Expect at least 4 months lead time if you want to do a similar project:

http://www.niekampinc.com/electric-g-tractor/

I custom fabricated the battery box, controls, etc. Used weatherproof/outdoor/marine components whenever possible.

So today I listened to all four(?) electric tractor podcast episodes whilst using my recently purchased non-electric tractor. It's 45Hp, very much like the John Deere tractor Paul used to own.

I was putting in a fence, which involved carrying a bunch of stuff out to the site in the bucket, and then a repetitive cycle of digging a hole (perhaps taking a minute or two) and then ramming the earth in with a crowbar for 10-15 minutes, then moving the tractor to the next hole location (maybe another minute, by the time I got it lined up - the treeline prevented me from just driving along the line of the fence).

Please refer to the attached photo.

Anyway, I had the following thoughts:

Given the amount of downtime, and the fact that I was never using anything like the 45Hp available from the motor, an electric tractor with a shade mounted array doing this job would probably be "energy neutral" at the end of the day from this sort of use. I did at least turn the tractor off whilst I was using the crowbar, but I suspect many possibly would just leave it idling away. The post hole digger attachment running off the PTO (for it's rotation) and three-point hitch (for raising/lowering) sucked compared to if it just had an appropriate direct-drive motor on top of the auger. You'll note it's not hanging vertically because the auger weighs about the same as the PTO shaft, which is pulling the gearbox down. This meant I actually had to reverse the tractor a little once it had started digging - using a heavy clutch in front of me whilst looking backwards to see where I was going. Also, the hydraulics in the three-point hitch are obviously set up for lifting something near it's maximum capacity (about 1500lbs), so this relatively light attachment would tend to fly up and flail wildly. So I started disengaging the PTO (more forward facing clutchwork) before lifting the auger out of the ground.

My final thought was that an electric tractor with an electrically controlled post-hole digging attachment could be controlled from the ground next to the hole, rather than six feet away on the tractor.

On the plus side, I umm-ed and aah-ed about the tractor for a long time, until a Geoff Lawton interview on The Survival Podcast where he said that earthmoving was more subtle than brain surgery, on a planetary scale. I did find myself wondering what I would do with it when diesel fuel got prohibitively expensive - I guess now I know at least one option, convert it to electric!

Heath Gilbert wrote:Interesting! I assume that practice is old school and is no longer used on our modern machinery?

Hi - just noticed this post. My brand new tractor was delivered to me (about a week ago) with its rear wheels 90% full of water. It didn't come with weights on the front because it has a loader (the weights were an optional extra, however). It has a running weight of about 5000lbs, including the loader (and water in the wheels).

I just got a second damaged electric wheel chair. Now I have 4 - 24 volt DC motors. 4 wheel drive tractor is on the drawing board. oh yeah.

I built this tractor to be a versatile tool around the farm.

Fast, fun, practical.

G'day,

If you don't mind me asking, how much did you pay for your (12Hp?) DC motor?

Phil

The motor was made by Advanced DC Motors, Inc and is their model #A00-4009, described as: (24V - 72V) 2HP - 12HP.

There are quite a few sources for these on the web, they can be had for around $700 new with a bit of shopping around.

A salvage electric golf cart is another angle to approach, though their input shafts can be a little funny.

There are other electric tractor nuts out there? Yeah!!!

My hubby n I are proud owners of a GE electric tractor. We got it in 2006 from a guy in WI for just $800 and it came with a snow blower, front mower and tiller.

It's the biggest model they made of the electric tractors and we put 8 15watt solar panels on a top rack, which worked ok for a single summer but won't do anything over winter.

Hubby cannibalized the snow blower motor and we plan on using it as a semi-portable wind generator to charge it over nights. We got a plow for the front instead of using the snow blower, but again, it won't take the sub-zero temps here.

And, we don't plan on using the mower as we have No Mow Grass and if we do need the lawn cut, well, once a summer we can let the sheep n goats out and call it good.

Things we have been looking for is of course, a chain saw system to go with it. We might go with a rechargeable saw as the e-trak can recharge anything no problem. It has no problem hauling a modified truck bed trailer full of wood but we have to be careful how we load the wood in the trailer since it can tip the tractor if it's loaded front heavy.

We also want to remove the solar panels to drive it into the barn to clean up bedding, pull in a small grain bin and other chores around the farm. and, of we ever get around to it, outfitting the hay cutter and baler with its own power system would mean the elect-Trak could even do the hay. One day!

I've seen some very elaborate attachments for these, including a small backhoe or a front load bucket and always have my eyes out for them but it doesn't take much to make these the only tractor a small farm needs.

Solar Electric Tractor Model 12 - Steve Heckeroth



https://permies.com

Steve Heckeroth shows his Model 12 electric tractor. This one is 20 horsepower, although since it is electric it has power comparable to a 40 hp diesel or a 60hp gasoline tractor. Steve explains how this has to do with torque peak performance of the electric motors being so much better than gas or diesel.

In this video we see the loader in action. The three point hitch and the PTO (power take off). We move some bales of straw and do a little bushhogging.

One problem with electric cars is range from the charging station. But an electric tractor rarely strays far from its charging station.

Another problem with electric tractors is battery weight. But with an electric tractor, the extra battery weight gives better traction!

This electric tractor is solar powered. The whole homestead is solar powered! And Steve has a solar electric car too!

Steve talks about using hydraulic pumps for things like the load vs. linear actuators.

Steve mentions the porsche spider he once converted to an electric car.

The solar electric tractor is labeled SolTrac and Steve says that he is changing the name to SolecTrac.

We see the thing film amorphous solar stuff on his barn roof. Peel and stick roll out solar panels. 8kw (kilowatts).

Lithium batteries. 48 volt pack. Battery management system. Each cell is monitored during charging. A/C to D/C converter. A/C motor. Most electric cars use higher voltage for greater speed. 48 volts is great for a tractor. This tractor has a transmission including hi/low range. Linear actuators for the steering. Steve thinks this is better than hydrostatic.

Use a low geat for rototilling or mowing and a higher gear for using the loader.

Regenerative braking. $15,000 for an electric farm tractor. $30,000 for the fancy electric tractor (sans solar).

music by Jimmy Pardo https://permies.com/t/6301#62570

We really need to get more information out there about these tractor conversions. It's great that all these Aliss Chalmers G's are getting done but I would love to see some of the more popular tractors get converted. There were nearly 400,000 Farmall H tractors produced compared to 30,000 AC G tractors. I would love to see every small farm have one of these old tractors converted to electric.

Does this "model 12" support the easy battery swap talked about in the podcasts? Paul, do you have video of how Steve does the mid-day, quick pack swap?

Kerry Rodgers wrote:Does this "model 12" support the easy battery swap talked about in the podcasts? Paul, do you have video of how Steve does the mid-day, quick pack swap?

That was an earlier model. This model does not have that feature. And he didn't have one that did this there.

He seems to be saying 20hp is the same as 60hp based on PTO performance. Yet I doubt you would have a PTO shaft spinning with 60hp of force, that would probably break a few things, so not really a worthwhile comparison, and the reason most PTO shafts spin at 540rpm is because that is what most machinery is designed to handle, again a faster PTO is not relevant. With those nits picked, sounds like a good way to go if you are going to do a lot of small scale rototilling. Would have been nice to see him dig a hole with the FEL. I wonder what 100hp would look like with battery power.

The TORQUE of a 20 hp electric motor is about the same as 40 hp diesel or 60 hp gas. Torque is what starts/keeps you moving, HP is what makes you go fast. That much torque will break things sized for that small of a tractor.

I would have to change how I work if I switched to electric, but that would be fine for everything except making hay. My problem is the cost vs. payback--I can build a fuel plant, either biodiesel press or alcohol still, for way less. But I have enough land to dedicate some to fuel production.

Torque is baisically a function of the gearbox, 3 different 20hp electric motors could all have different torque. However if I had a 20HP motor hooked up to the PTO, and a different motor hooked up to the drivetrain, then when I use the PTO I effectively have a 40HP tractor. HP is a measure of power, nowdays we mostly use Watts, but for old cars and tractors we still talk about HP for some reason.

any idea what he used for a donor for the model 12, for rear end etc.
gary

I'm new to this list having followed a link from the electric auto association on Steve's tractor #12, so little introduction and some G stuff:

I've been into organic food and living ideas for a long time, before the legal definition, involved with NOFA when I lived up north. Along the way went to many workshops with presenters I now know as permaculture authors. I'm also into alternative energy and electric vehicles, on-road and electric tractors. I started out with a converted S-10 pickup truck and a GE Elec-Trak. After getting into the Elec-Traks, the parts supplier of 30 years in Wisconsin retired from that business and... it ended up with me, so I have a warehouse full of parts and blueprints etc. which I'm slowly listing on-line. Since moving to VA got lucky with some state rebates so have 12KW of solar on the shop roof and 2 KW on the house.

It is nice to find a place with others who share all the same intersecting interests. In response to the Electric G comments, I've worked on a G conversion, starting out with the Niekamp kit after visiting Ron on his farm (before he sold off that tractor). I ended up with a different design, but still have that kit sitting around unused. I'd love to find someone who wants it - I can get some of my money back and the new owner gets it way faster than 4 months turnaround since siting here ready to go. Also have a matching motor and controller if desired.