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Comment by Kyragem | Hacker News Reader

These trucks can all be charged with 240V whereas the Tesla semi requires a 1000V (mega charger) which isn't available anywhere yet. So these trucks are all contending with being far more practical.

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There's a difference between AC and DC charging. All current Tesla's accept 240 volt AC and there's no reason to expect that the semi won't either but with the such a giant battery pack 240V will simply not be fast enough. The 1000 volt is for DC fast charging. Tesla's current models use 350-375 volt battery packs. 1000 volt will just allow them to charge faster for DC fast charging, and more efficiently.

To add to this, for AC, there is a conversion stage (ie inverter) that needs to convert it to DC to charge the batteries. This unit, at the currents that the Semi requires to be charged in a reasonable amount of time will be wasting too much energy in conversion losses.

Due to its inpracticality, AC charging is unlikely to be an option, but maybe they include it for those exceptional circumstances.

Existing Teslas can accept various voltage for charging. Obviously, the lower the longer to charge. Pretty sure the Tesla Semi CAN charge at up to 1000V, but doesn’t require it, while the competitors CANNOT charge at 1000V.

What's your source that Tesla Semi can't be slow charged with 240V? I'd be pretty shocked if that was the case.

I read it as "requires 1000v to get the charge speeds advertised" - at 240v the trucks would all charge at about the same rate, and 240v may be what everyone goes with (though I doubt it, might as well install a dedicated charger if you're buying a truck).

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