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Comment by usrusr | Hacker News Reader

With the impeding electrification we might eventually see walkers on skis-shaped feet, as a compromise between load distributed over a large area and a narrow tread not usable for growing. They'd also excel in the metric of total traction per peak surface load.

Key technology of electrification would be tethered drone swarms that feed from the cable they carry, because I'd assume that you'd want to separate batteries from your actors so that they are flexible you work from grid infrastructure just as well as from some battery truck tagging along on an access road (which brings us back to surface load, you wouldn't want the battery loading soil you still want to grow in).

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As a John Deere Employee I have to be careful what I say.

I will say (because this is obvious from public information) that we are "looking" at electric tractors, but making them work is hard. 10 years ago we stuffed as many batteries as we could in a 100 horsepower tractor, and for 45 minutes it when head to head with a similar diesel tractor, then the batteries were dead. 100 horsepower just above a small tractor these days. Remember a Tesla might be able to produce 500 horsepower (I can't be bothered to look it up, but something very large like that seems reasonable), but to maintain speed on a freeway it only needs about 20 horsepower. A tractor is expected to produce the rated horsepower for 10 hours non stop.

Your idea of a feed cable is something we have looked at (you can find an announcement, though it might be in German). There are a lot of issues with making it work in the real world, though it might be where things go if diesel gets a lot more expensive.

There's also a chart explaining the issues of battery electric tractors by Jason Bradford in "The future is rural": https://twitter.com/vivekgani/status/1426017955398176770?t=0...

Basically when ya chart out gravimetric and volumetric density stuffing batteries doesnt seem to make sense. There may be some other options (feed cable, slower cycle, etc.)

https://electrek.co/2021/12/15/john-deere-buys-kreisel-elect... makes me think John Deere is very much looking into electrification.

It seems people (outside the agriculture industry) underestimate what todays tractors (and even more so harvesters, etc) can do and how much power that requires. Harvesters running 12-24 hours a day for days or weeks seem way out of reach of what the current battery technology can accomplish.

I'd bet on hydrogen engines (at least in the next 5-10 years) for larger machines.

On the other hand tractors are multipurpose tools and it highly depends on what it will be used for. If the tractor is only expected to run a few hours a day then batteries might actually work

I'd bet on hydrogen engines...

Since the infrastructure already exists wherever there is serious agriculture, we should probably call that "liquid anhydrous ammonia engines". NH4 is a more practical carrier for hydrogen than its elemental form.

Running cabling on irrigation pivots or other existing infrastructure might be an option. Wouldn’t work for flooded fields, of course.

Has anyone tried standing up a cable car-like system where overhead lines pull (and power) the tractor? You could use wind turbines as the poles that keep the wires up in the air (though I suppose you could also use subsurface cables but that would reduce the growing surface a bit; then again, there's always space between rows of crops).

In the horse age things like that were tried. It isn't practical to setup in a large scale, but if fuel prices continue to go up weird things might be more practical than fuel...

Something like https://www.youtube.com/watch?v=OJ9xKxAtDa8 I forgot about this video yesterday. (skip the first 45 seconds or so)

I forgot the obligatory I don't speak for my employeer

If ski-feet walkers made sense, I don't think they'd be gated by electrification. That seems like a job for hydraulics.

https://blog.machinefinder.com/3255/john-deere-walking-harve... for example.

Whoa, anime is real!

I would have thought electrification might work well on very specialist machinery - perhaps around horticulture, vinyards, greenhouses, etc.

But part of the appeal of a big powerful tractor is their huge versatility - you'd loose a lot of that if you needed additional infrastructure in place.

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