Electric Tractor

[vvanders]

Interesting. I've noticed a 30% drop or so in mileage on my outback..figured it was heat waste - taking the engine up to operating temp from 20F instead of 70F.

Hadn't give much thoguht to air resistance, though have thought about a dirty car (salt and such) and rolling resistance when teh road is mucky.

My MPG is back up in the car now - 440 on a full tank vs 320ish in the cold weather.

I have some li-ion power tool at the barn...when it's 20F they don't work - at all. Needs to be 30 or higher.

Yeah, it's pretty easy to see when the wind switches from east to west here too.

Li-ion doesn't like low temps but not because of discharge, it really hurts capacity when they're outside operating temperature the voltage is also lower until they warm up which is probably why the tools cuts out.

All EVs have thermal management these days(basically packs submerged in coolant) for that exact reason. Most have pack heaters to keep the cells from getting cold soaked. The good news is that if you stay in the thermal envelope you have very little degradation in total pack capacity.

 

[BertZegers]

My Kubota tractor is 20 years old, my Zetor tractor is 45 years old, and my mini excavator about 40 years old. All still going strong and used a lot. All diesel engines.

If they were electric they would have been scrapped a long time ago, because of the replacement cost of batteries.
Electric vehicles are charged with electricity that is generated by almost 100% fossil fuels, including 50% coal (in the US). Then why not use the fossil fuel in the machine?

In Canada our government will carbon tax fossil fuels to the extent that is not longer affordable to use them, although Canada produces only 2% of the worlds carbon.

Cars might be a different story. but the thread is about Electric tractor.

 

[BertZegers]

Many factories are full of electric forklifts, crash wagons, scooters, and flat beds. Slow speed vehicles are easier to electrify than 80+mph ones. The road going vehicles do offer regenerative braking to charge the batteries. Back in the 60's, the military was experimenting with making a electric Cat D9.

Inside a building you rather have electric vehicles than internal combustion engines. The reason is the toxic fumes in gas and diesel exhaust.
Low temperature is also not a factor in heated buildings. There are also a lot of propane forklifts used inside buildings, because of the cleaner exhaust fumes.

 

[vvanders]

My Kubota tractor is 20 years old, my Zetor tractor is 45 years old, and my mini excavator about 40 years old. All still going strong and used a lot. All diesel engines.

If they were electric they would have been scrapped a long time ago, because of the replacement cost of batteries.
Electric vehicles are charged with electricity that is generated by almost 100% fossil fuels, including 50% coal (in the US). Then why not use the fossil fuel in the machine?

In Canada our government will carbon tax fossil fuels to the extent that is not longer affordable to use them, although Canada produces only 2% of the worlds carbon.

Cars might be a different story. but the thread is about Electric tractor.

Let's keep policy/politics separate from the technical side of things. If you want to dig into that side feel free to start another thread.

Yes, batteries degrade but everything else is simpler. With battery price dropping it may not be a big deal to overhaul every 25 years. I've got 86k miles on my 85kwH pack and only have 8% degradation.

I'd even be interested in a battery free(or maybe large supercap to smooth power draw) combined with a diesel generator. VFDs don't slip like other drivetrains, one the wheel starts moving faster than input speeds the magnetic field works in reverse to bring the wheel back to speed rather than spinning out.

 

[Agvg]

Tesla's seems to handle low temps well, here I Norway there are Tesla's everywhere and it works.

Electric cars have ca 50% market share.

 

[Professor Marvel]

I see some very interesting information here.
I am not opposed to electric vehicles and in fact as my use of yard equipment has lessened i have even started using battery operated chain saw etc. They still do not compete for extended or heavy use but they work well for most activities i do anymore.
When it comes to vehicles (and i assume this applies to tractors) it seems to me that both battery life and cost are not there. At this point the only reason we see a proliferation of electric cars is because the powers that be infuse HUGE amounts of government money into pushing them.
There are subsidies going into the build of the cars.
There are subsidies going into consumer purchase of the cars.
Non electric alternatives (gas diesel etc) have huge taxes to force their costs up. Once again creating a false apples to oranges type of comparison.
The actual electric cost of filling up has never been compared to me apples to apples. IE how much fuel does it take to charge a tesla vs drive a gas one.
What is the REAL environmental impact to mining and building the batteries that do exist at this point.
AND ALSO Not to be ignored, the press touting their one sided view of the wonders of electric vehicles, ignoring any and all downsides.
Some day they might have and probably will have legitimate functioning electric vehicles but i don't believe they are hear now without tax dollars being spent en masse. And I do mot like any industry being created and infused perpetually by tax dollars.

 

[mopardude318]

Nope. Wouldn’t buy one. I’ll stick with diesel. Diesel truck. Diesel tractor.

 

[Fuddy1952]

Nope. Wouldn’t buy one. I’ll stick with diesel. Diesel truck. Diesel tractor.

Where is the like button?
It is interesting ,educational and thought provoking.
I remember a couple years ago our local Lowes store had an interesting riding mower, made in NC. Can't remember the name but it was gas/electric. Interesting design because it was a mower and generator. So you could ride it where you needed A.C. power or power house during a storm. The blades turned independently by electric motors.
Innovative design.

 

[vvanders]

That's pretty cool, one less engine to maintain which is why I like our PTO generator.

 

[RSR]

Sub freezing temps are closer to 30% range loss in my experience over the last couple years. Heating ahead of time helps a bit but the primary loss at low temperature is air resistance. It goes up by V squared so cruising at 70 vs 60 takes 36% more juice. Anyone who's towed with a good headwind has seen this in their mileage.

Good news is my Kubota tops out at 15mph so we won't be worrying about air resistance there.

While you're right that pressure drag increases as velocity squared, it's actually worse than that. Power = Force x Velocity. The drag force varies with velocity squared, but the power (what really matters) increases as velocity cubed. So, if you double your velocity, the power to overcome it is 2^3 = 8 times as much.