alt Hacker NewsI explained this in my other comment but I'll paste it here:
The thing is that ICE vehicles are so inefficient to begin with, but a towed trailer needs the same amount of energy regardless of what is towing it. Imagine a trailer takes 1 unit of energy to move, and ICE truck takes 5 units to move itself, and EV truck takes 1 unit to move itself.
The ICE truck towing it would go from 5 units to 6 units, reducing the range by 16%.
The EV truck would now go from 1 unit to 2 units, reducing the range by 50%.
So the better your efficiency, the worse you are at towing. Ideally EV trucks would have such a huge battery that even when the range is reduced by 50%, it is still as long as a gas truck's range, but modern battery technology is still too sucky to achieve this.
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That's part of the answer, but the other part is that towing is going to reduce range significantly regardless of your fuel. With a gas or diesel vehicle that's not a big deal, because you can fill back up in 5 minutes or less. With an EV, it takes 20+, and the fast charging locations are less plentiful than gas stations. If you're not towing, that doesn't matter too much, but when you have to charge 2-3 times as often due to towing, it becomes a real issue.
This would only make sense if the EV efficiency gain were due to lightness of the vehicle or better aerodynamics. It's definitely not the first, and don't imagine the second is a big factor but maybe I'm wrong. I'd even expect EV to help here because a heavy trailer takes more energy to get moving that can be partially recouped when regen-braking.
Is it just that these EV trucks don't have multiple gears to tune themselves for towing? Like how many EV cars are geared for city speeds but suffer on the highway. I know dual-motor ones have different ratios, but that's still 2 speeds vs 6-10. Edit: Could also be about engine tuning.
I'm confused by where efficiency comes into this.
The efficiency is usually defined as the energy the car can use to move itself over the energy going in (electrical, or chemical for gas). If an ICE is 20% efficient then using 5 units means you get one unit out. Towing a trailer that doubles the load means you need 2 units out, which means you need 10 units in. So you get half the range either way.
The engine doesn't get more efficient just because you hook a trailer to it: it's still 20% efficient regardless.
I think you're missing the cost of ownership in your efficiency calculation. EV's without incentives cost a lot compared to ICE so much so that the savings don't equate usually until I hear year 4 of ownership. Now that's getting better I mean look at the new Bolt or Ford Fathom 30k Retail usually (which I think is where there's a lot of room in small midsize trucks and EV's)
>So the better your efficiency, the worse you are at towing
The fuck?
best explanation of towing I've heard great job.
Once I discovered that the entire EV battery holds only 2 gallons-of-gas-worth of energy (roughly about 65kwh) , all of the range issues made a lot more sense.
I don’t think this is true at all. If towing the trailer doubles the energy required at the wheels (and both engines maintained the same efficiency under the additional load) then both ranges would be halved.
In practice, diesel engines can become more efficient under additional load, and it obviously varies between models but it’s not a 16% vs 50% difference like your example.
The reason EVs don’t tow well is they don’t have a high enough range to begin with. Diesels have nearly double the starting range of an equivalent EV, and storing additional fuel on board is an option.
So the EV still beats the ICE vehicle threefold (2 units vs 6 units), it just _feels_ worse (half as efficient as without a trailer) so you declare it _is_ worse.
With that type of reasoning, let me guess, the competitor you work for is General Motors?
Dude, your comment does not compute.
Care to clarify with actual math? We are a technical audience here.
This analysis doesn't make sense to me.
An ICE vehicle isn't less efficient because the frame itself takes more energy to move, it's less efficient because the engine burns off a high percentage of its energy as waste heat.
But that will be true regardless of what the load is. If the ICE truck takes 5 units of energy to pull itself compared with 1 unit for the electric truck, that implies that the the truck chassis only actually requires 1 unit to move, but the ICE engine burns off 80% of its energy as waste heat. The engine is only 20% efficient.
Now if you start pulling a trailer, you have (in total) 2 units of energy worth of load. But if the ICE engine is still only 20% efficient, then it will take 10 units to pull both, rather than 6.
I can believe that this effect is real (electric cars suffering more range loss when towing), but it seems to require an explanation beyond this one.