electric motor conversion for a BCS or Gravely?

[FredWalter]

A web search finds a bunch of 4-wheel garden tractors that have been converted to run off batteries+electric motor, but I have yet to find someone that has done this conversion with a BCS or Gravely tractor.

 

[RichardTX]

Electric power is too costly to be practical. I recently proved this when my son was thinking about getting an electric car. If I recall correctly, the break even point is at about $14-$20 per gallon of gas. It would be higher when doing a retrofit as all that technology comes at a rather steep price. If the Govt didn't mandate it and subsidize it, there would be no electric or hybrid cars made in any sort of production quantities.

If "green" is your concern, get a goat and possibly a horse. The problem with that solution is that the animals have to be fed and watered every single day whether they do work or not. That fact is part of what put Gravely in business to start with.

Of course, there is the problem of the pollution that people produce from just living. The only option there is to stop living on this planet. Not many people choose this option.

The bottom line is that very few have done an electric conversion and for some very good reasons. I would go propane (man made fuel) before going electric. Propane actually makes sense.

 

[RichardTX]

Electric power is too costly to be practical. I recently proved this when my son was thinking about getting an electric car. If I recall correctly, the break even point is at about $14-$20 per gallon of gas. It would be higher when doing a retrofit as all that technology comes at a rather steep price. If the Govt didn't mandate it and subsidize it, there would be no electric or hybrid cars made in any sort of production quantities.

If "green" is your concern, get a goat and possibly a horse. The problem with that solution is that the animals have to be fed and watered every single day whether they do work or not. That fact is part of what put Gravely in business to start with.

Why even bother cutting grass? Let it grow. It is good for the environment.

Of course, there is the problem of the pollution that people produce from just living. The only option there is to stop living on this planet. Not many people choose this option.

The bottom line is that very few have done an electric conversion for some very good reasons. How much work can a tractor do before it needs to be recharged?

I would go propane (man made fuel) before going electric. Propane actually makes more sense.

 

[kiotiken]

Electric power is too costly to be practical. I recently proved this when my son was thinking about getting an electric car. If I recall correctly, the break even point is at about $14-$20 per gallon of gas. It would be higher when doing a retrofit as all that technology comes at a rather steep price. If the Govt didn't mandate it and subsidize it, there would be no electric or hybrid cars made in any sort of production quantities.

I'd love to see the "proof" you provided your son. I've never done any math, but it would seem to me it wouldn't take long to make back the investment on an electric conversion for a car when it cost $60 (here anyway) to fill a small car and I believe about $10 to charge batteries to go the same distance (several charges of a couple bucks each).

There are no subsidies for hybrids, at least not here, anymore, and they sell just fine at a reasonable price. The car itself as been subsidized throughout history and you could make the case that gas powered cars are still subsidized by the healthcare system for the emissions they produce causing conditions such as asthma, lung and heart disease (read smog). There's always a way to say the true cost is higher because of x. Less informed people even try and put forward that charging a cars batteries can emit more than filling a gas tank because the electric power is coming from coal.

I don't have the answers about electric vs gas and I'm not going to be the first to jump on electric car wagon, but I embrace the new technology and it always bothers me that so many people try to fabricate reasons not to move forward.

 

[cmyoung2]

Haven't seen that type of conversion, seems size might be an issue, but think about the traction because of the weight. I did convert an old Ariens tiller to electric, using an old 1 1/2 hp motor. It is 110v, use a long, heavy power cord. It fits in the raised beds and other tight areas the BCS can't fit. Works like a charm, but a little heavy. Think it would dig to China if I let it.

 

[farmerboybill]

Hey Fred,

Long time, no see. What have you been up to? Still got all them BCSs in the bus?

I've seen those Allis Gs and such converted to electric, but I agree with CM, you're gonna have a weight issue - not necessarily the motor, but the batteries. The Allis has the advantage of being big enough to carry around 400 lbs of batteries, but a two wheel tractor would be pretty clumsy at 600+ pounds. You could run smaller battery packs, but then you'd be limited on runtime. A long drop cord would be OK if you're close to a power source and are mindful of the location of the cord. If the battery technology would improve, it'd be a good unit - quiet, no emissions,, gobs of torque, an on/off switch instead of a clutch, can be charged off solar panels. Frankly, no downside.


Richard,

I too would like to see your calculations. As far as I see it, the limiting factor in electric cars, trucks, bikes, tractors is the electrical storage. Current batteries are not capable of replacing the convenience of internal combustion.

I can see the regular arguments against electric cars - Low on gasoline? pull into a station and be back on the road in 10 minutes. Low on electricity? Sit around for several hours while the car charges itself. Run outta gasoline? Walk 5 miles and bring a couple gallons back. Run out of electricity? Push. Wanna go more than 200 miles in an electric car? Sorry Charlie. Need it fixed? better be close to a dealer because Pa's Shadetree Service isn't gonna fix it.

120 years ago, when internal combustion engines were being invented, the same arguments were made. The world was geared to animal propulsion. Fuel was anywhere the horse could drop its head. You could put your horse up at a stable in every town. Any blacksmith could shoe a horse and a wheelwright could fix a carriage wheel. When automobiles came about, they were considered a rich man's toy for the first 20 years. Fuel was expensive and unreliable. No one could fix them when they broke and they broke often.

Fuel from the ground isn't ever gonna be "cheap" again. That includes propane, natural gas, crude, or coal. Sure it'll always be available, but at what price? 15 a gallon? 50 a gallon? Tomorrow's fuel is gonna have to come from the air - solar, wind, tidal, biofuels, etc.

 

[kiotiken]

farmerboybill, I agree with everything you said, except not being able to go more than 200 miles. Your point is sound, once you're out of juice, it takes a long time to recharge, and if you want to go longer distances today, you have to pay for the privilege, but check this out if you want to see the future of electric cars.

Tesla Motors | Premium Electric Vehicles

 

[small farmer]

I did the allis G electric conversion. The devil was in the details on that job. Bill is right about the weight. A lot easier to move with four wheels and a steering wheel. But if the BCS could have a powerful enough electric motor and a battery pack that weighed under 100 pounds so in the same ball park as a diesel engined tiller it would work. The battery pack would need to be like our cordless drills. Pop it out and charge it and put in the second pack while the first is charging. I think we are really close to a battery pack that would do that for us. If we can afford it.

 

[small farmer]

I forgot to add that the most important use for an electric tiller would be in Greenhouses. I have seven and really wish I could till with an electric tiller in them. I have seen a picture of a goldoni running on propane in a large Dutch greenhouse. The floor polishers for the big box stores are propane powered. I looked into propane carburetor but never went down that path.

Jim

 

[RichardTX]

it cost $60 (here anyway) to fill a small car

All gasoline costs pretty much the same the world over. It is the taxes on that gas that makes the prices different.

I have met more than a few people that left Canada and the primary reason they left was the high taxes. Don't worry, the US will catch up. As of this year, the USA has the highest corporate tax rate in the world....and people wonder why corporations are leaving the US.

 

[RichardTX]

Hey Fred,




Richard,

I too would like to see your calculations.

I spent a considerable amount of time calculating the true cost of recharging a battery and did not save the data. I am not about to do it again. The most time consuming part was finding out the true capacity of a battery in amp/hours.

Then there is the part where the electric car makers don't tell you certain facts like the AC and all other accessories were turned off for their range tests.

Anyway, my son checked my data and calculations and agreed. Electric is more expensive than gasoline. That is why he bought a gasoline powered car.

Speaking of gas, we are burning gasoline at a higher rate than ever before thanks to the EPA adding ethanol. The addition of 10% Ethanol decreases mileage by about 5-10% depending on conditions. The only conclusion I can draw is that the Government's priorities are a little different than what they say they are.

 

[farmerboybill]

I spent a considerable amount of time calculating the true cost of recharging a battery and did not save the data. I am not about to do it again. The most time consuming part was finding out the true capacity of a battery in amp/hours. .

Basically, you're saying "Trust me, I know what I'm talking about". Sorry, I don't personally know you, so I don't trust you... Until you show us your "considerable work", I'm just gonna assume you pulled a number out your number two.

We do agree that "for right now" electric cars are not feasible. Where we disagree is that you seem to think they will NEVER be viable. I think within 10 years there will be a car that the average citizen can afford and can go 500 miles with the A/C on without worry . It's gonna require having a standardized, smaller battery like small farmer mentioned that can be swapped out within 10 minutes at a fueling station, and to have these stations at every street corner just like current gasoline stations. It's also gonna require better PV solar cells on the vehicle to extend distance when the sun is out and provide an option to power up without calling a tow truck if you run outta juice - and power your A/C. It would also be smart to have those same PV cells on your house roof to charge the vehicle off the grid. In fact, the fueling station could also have PV cell panels and wind turbines to charge the batteries they swap between vehicles.

Right now we're at the "rich man's toy" stage. I'm sure not gonna drop $70K for a 300 mile range Tesla, but some Hollywood actor looking to make a point might. As sales go up, prices go down, technology gets better, prices go down again, sales go up, prices come down, etc, etc, and BANG millions of electric vehicles on the road by 2022... The faster fuel prices go up, the faster this will happen.

That, or we could just keep using gasoline, diesel fuel, natural gas, propane, coal on into the future with no other plan for when fuel DOES reach $14-20 a gallon...

 

[RichardTX]

Basically, you're saying "Trust me, I know what I'm talking about". Sorry, I don't personally know you, so I don't trust you...

Good for you. Question everything. Assume nothing. More people should apply critical thought to more things. Who knows, I might be wrong and I am willing to accept that.

It is actually pretty easy to estimate. Convert HP to KW (746 watts=1hp) and then the rest is easy. Consuming 1000 watts for 1 hour is 1 KWH.

My son pays a whopping $0.27 - $0.32 per KWH depending on time of year, etc. It seems really high to me, but that is the price in the part of Europe where he lives.

 

[oldmech]

Hi! We can have electricity FREE from sun or wind and FOR EVER .I have now a electric tricycle for five weeks. I make 16 kms for .03 electricity is about .06 kwhr here . Hydro use electric car cost is 10x less than gas. But batteries are too expensive . We must calc the cost of battery by hour.or divide by kwhr . The battery cost by kwhr is very high more than electricity. Good luck! Oldmech

 

[RichardTX]

That free electricity isn't free. Someone has to pay for the generating equipment and the payback on that is at about 20 years the last time I checked. Then there are bearings that will wear out. I am sorry but it isn't free.

The short story is there is no free lunch.

Battery costs are high and have a finite lifetime. I did not even factor that in. Thanks for that reminder. On the other hand, engines don't last forever either but well maintained, a premium engine should last between 6000 and 9000 hrs between major overhauls.

BTW the earth is doomed and will not last forever. It will either get thrown out of it's orbit around the sun due to a collision with another solar system or will get engulfed by the sun when the sun turns into a red giant. It will just take a while before either of those events occur.

 

[RichardTX]

Here are my calculations for a 12 hp electric motor operating at 100% efficiency.

12 hp * 746 watts = 8952 watts

If that motor is run for 1 hour it consumes 8.9 kw hours of electricity.

8.9 kwh at $0.12 per kwh = $1.07 per hour to run.
8.9 kwh at $0.27 per kwh = $2.16 per hour to run.

Factor in the efficiency losses of the motor, controller, etc and the cost creeps up. Then there is the extra weight of the batteries to haul around, battery replacement costs, etc.

 

[mpapiary]

"BTW the earth is doomed and will not last forever. It will either get thrown out of it's orbit around the sun due to a collision with another solar system or will get engulfed by the sun when the sun turns into a red giant. It will just take a while before either of those events occur."



Lets hope that his calculations about this happening aren't accurate!:laughing:

 

[brokenot]

This isn't a conversion....just someone's home build.

Walk behind electric tractor. - YouTube

I've thought about doing something similar just for fun. I have access to piles of motor controllers, contactors, motors, pumps, throttle pots, etc. because I work at a rental facility. Places like eBay are excellent sources for bits and pieces as well.

If you enjoy browsing online auction sites like K-Bid like I do, you'll also stumble upon lots of parts and/or complete machines being sold dirt-cheap because chargers don't work/batteries are bad/whatever. Types of equipment that could be sourced for parts for your project include scissor lifts, floor maintenance machines, powered pallet jacks, warehouse stock-pickers, golf carts, etc.

There are also a lot of places that sell new, rebuilt, or exchange components like motor controllers.

I say go for it. Post photos of your progress!

 

[small farmer]

One of the concerns for an electric two wheel tractor is how hard the electric motor would be working. I think that the electric motor would be working hard more of the time than in a car application. We won't need a clutch though. Just imagine doing your work with out ear protection. No diesel noise to bother the neighbors with. I guess that's good or bad depending.

jim

 

[RichardTX]

"BTW the earth is doomed and will not last forever. It will either get thrown out of it's orbit around the sun due to a collision with another solar system or will get engulfed by the sun when the sun turns into a red giant. It will just take a while before either of those events occur."



Lets hope that his calculations about this happening aren't accurate!:laughing:

Unfortunately they are quite accurate. It is unknown what will exactly will happen when our solar system will collide with another, but the sun engulfing the earth is a sure thing.