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Re:Big oil will die when it becomes cheaper to hail an elect... by epistasis on Friday July 07, 2017 @01:02AM (#14716202)
Trucking is one area where the per-mile costs are really important, unlike most passenger cars. The cost of electricity is generally much much less than the cost of fuel, so there's definitely the potential for a compelling offer for hauling, even if its only a subset of all uses of semi trucks.

Electric drive trains are excellent at heavy loads; many huge haul trucks, trains, etc. use diesel electric where the diesel is just a fuel source to generate electricity for the real workhorse, the electric motor.

So it's really just the battery that's the hard part here.

Most EVs get ~3.3 mi/kWh. If the increased air resistance means only a third of that efficiency, a 450 kWh battery would be sufficient for 500 mile range. That's about 3 tons of weight, which is a lot, and take up about 2 feet of space behind the cab, perhaps. But since a diesel engine itself is going to weigh about 1 ton more than the electric motors and inverters, it's not a completely outrageous amount of overage.

Of course, the battery alone for this would be about $100,000k, as much typical tractor cabs these days. So clearly there would be some sort of swap program, and battery usage would be charged.

This all becomes a ton easier if designed for just, say, 250 miles before swapping batteries. But napkin math suggests that 500 miles isn't completely implausible, if you can get over the up front capital costs, and the slightly lower hauling capacity.

Re:Big oil will die when it becomes cheaper to hail an elect... by stannol on Friday July 07, 2017 @03:05AM (#14716644)
> Most EVs get ~3.3 mi/kWh.

Not even close. BMW runs electric trucks between production facilities and our 169kWh trucks (Terberg YT202-EV) which haul up to 34,000kg get at most 100km out of that, often less. So you're looking at about 0.6km/kWh or 0.37mi/kWh. It will be more with less stopping (although there isn't a lot of stopping on our routes) but nowhere near your estimate.

Re:Big oil will die when it becomes cheaper to hail an elect... by epistasis on Friday July 07, 2017 @03:13AM (#14716667)
I appreciate your data! However I wasn't trying to say that trucks will get 3.3 mi/kWh, this was apparently quite confusingly phrased, as I meant passenger vehicles.

My spitball of 1.1 mi/kWh was clearly way too high still.

Re:Big oil will die when it becomes cheaper to hail an elect... by ams6110 on Friday July 07, 2017 @01:07AM (#14716221)
> Most EVs get ~3.3 mi/kWh

Not if they're hauling around 40,000 - 50,000 lbs of freight.

Re:Big oil will die when it becomes cheaper to hail an elect... by epistasis on Friday July 07, 2017 @01:16AM (#14716252)
And in the next sentence I completely spitball that it may be a third of that.

That's based on the drag, which is most of the energy spent on hauling.

Though another benefit of electric is that the kinetic energy of accelerating 50,000 lbs to 55mph can be regenerated, instead of lost entirely. And it's not an insignificant amount of potential energy, at really close to 2kWh.

Re:Big oil will die when it becomes cheaper to hail an elect... by kamaal on Friday July 07, 2017 @01:07AM (#14716220)
Also don't forget the battery charging time. If your battery takes two days to charge, it will be show stopper to even start with.
Re:Big oil will die when it becomes cheaper to hail an elect... by epistasis on Friday July 07, 2017 @01:11AM (#14716231)
Well I did say: "So clearly there would be some sort of swap program"

Though my intent was mostly so that the capital cost could be amortized over many uses by independent truckers, rather than them having to take out an upfront loan for the massive cost of the battery. But it also makes the timeliness of charging a non-issue.

Re:Big oil will die when it becomes cheaper to hail an elect... by kamaal on Friday July 07, 2017 @01:40AM (#14716339)
Swapping is an option if the batteries aren't owned by the drivers/truck owners. Otherwise its a huge issue.

I don't want to buy a new truck and have my new battery swapped for a 5 years old battery, then have a break down somewhere and pay for it.