I was thinking about this a bit this evening.... and I think Semi's potential for Tesla itself is pretty amazing in its own right when combined with Supercharger V3. Consider that the latter is well more than 350kW and battery buffered. What happens when you put one on the back of a Semi trailer, including its corresponding pedestals? Well, first, you get the ultimate roadside assistance vehicle. Drive anywhere and it can rapidly fill up vehicles (several to completely full, or dozens with enough to reach the next charger, on a single charge). Since V3 should only weigh perhaps 4-5 tonnes or so, and not take up a huge amount of space, you still have a flatbed to haul back any vehicles with more serious problems. Furthermore, if there was predicted to be a shortage of superchargers at some point - say, for a festival, or some big event (like the eclipse), Tesla could have such trucks drive out to important areas. They'd still need to be wired into the grid, but that's all they'd need. In most places, applications tor temporary grid connections are much easier and faster than permanent ones. On the other hand, if instead of leaving an empty flatbed, you fully load it with either a grid-scale mobile generator (which get easily into the megawatts), or a grid-scale Powerwall (like Tesla is doing for Australia).... Then you have the ability to be an instant portable supercharger. No need to be anywhere near the grid - you just show up, and people can supercharge, so long as you can keep the fuel flowing or the Powerwall filled. Trucks with emergency generators are already godsends in disaster zones, and portable supercharger trucks could be deployed to such emergencies as well. Contrarily, if one is willing to scrap the "instant" part, the bed could contain solar panels, framing, and earth anchors. While it would take some time / labour to set up, you could have at any location A) the ability to power vehicles indefinitely, B) the ability to provide power to local services indefinitely, C) an onboard battery to buffer consumption (for charging, for uneven grid usage, for low-level nighttime use). Festival in the middle of nowhere? Refugee camp? Military base? Check, check, check. Most importantly, whatever ability it provides to others, no matter what configuration you use, it can use for itself as well. If it runs low on range? It could use its own supercharger to add more (more to the point, if they wanted to they could have a direct connection to the Semi with no need to stop to hook up). Have a generator or a grid-scale powerwall? Same story. Etc. A diesel semi could certainly also carry any of the above hardware configurations, but does not benefit from its own cargo. I think there's a lot of appeal to the concept of electric trucks carrying around fully-contained, ready-to-go, battery-buffered superchargers.