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Comment by ProfessorLayton | Hacker News Reader

>The Tesla semi, which is an electric truck, can take that same load and move it 200 miles.

What hasn't been discussed here is weight limits. It won't be possible to transport the "same load" if the semi is using a lot of its weight budget carrying a battery vs a diesel truck. The U.S. federal road gross weight limit is 80,000 pounds (20k per axel).

For reference, a Tesla Model Y's battery weighs 4,416 lbs

It seems like they'll be limited to significantly smaller loads and require more trips or drivers to move the same amount of stuff, unless there's another revolution is battery energy density.

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Exactly. These calculations make it sound like propelling the vehicle itself from A to B is the goal. Nope - the goal is to transport goods from A to B within practical size and weight limits/restrictions. If the volume and weight capacity are cut in half, that needs to be considered. Not to mention significantly increased wear and tear on the tires and the road infrastructure, and the impact of the mining required to make the battery.

Has anyone done a similar calculation for a real-world scenario?

The solution is more axels. Haven’t you seen cement trucks with the deployable 3rd axel?

And the weight limit is 160,000. You forgot the 2nd trailer

Even so, diesel with a 2nd trailer >> electric with a 2nd trailer, which changes the economics in a non-trivial way. There's also the question about how to pay for road wear, which is currently subsidised by consumer vehicles, as the diesel tax falls far short of paying for itself, while there's no tax infrastructure for electric yet — that will also impact the economics of this.

I'm a full proponent of electric vehicles, but full electric doesn't seem quite ready for semis. Perhaps hybrid is the way to go vs full electric, at least until the battery tech catches up.

I don’t know what it costs, but adding an axle doesn’t come for free.

If it did, those axles would always be on the ground. So-called “lift axles” can be raised because keeping multiple sets of wheels on the ground makes cornering harder, increasing tyre wear and energy usage.

An entire Tesla Model YT weighs 4,416 lbs, the battery alone is closer to 1000 lbs

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