Meet the Megacharger Tesla Megachargers are a new kind of charging depot with more space, more voltage, and more battery storage to charge big truck batteries renewably while cushioning the load on the local power grid. Prototype Semis have been seen charging at Superchargers by connecting several charge cables to the truck at once, but that seems like a development workaround rather than a go-to market suggestion. I thought I heard wrong when Elon Musk said Megachargers would be able to deliver a megawatt of power, four times the power delivery of the most potent Superchargers installed today, but it makes sense given the truck's presumed battery capacity. 3 motors, but only sometimes That juice feeds three motors, only one of which is used when cruising, while the other two, ganged on one of the axles, kick in only when acceleration is needed. Each motor is the same patented type as those in the Tesla Plaid models. You may laugh at 0-to-60 time of 20 seconds but that's impressive from a truck that weighs 17 times a Model S Plaid and is aimed at efficiency, not performance. The Semi has three motors borrowed from the Model S Plaid, but needs just one of them to cruise at a steady pace. Tesla A Tesla clip of its truck blowing by a traditional rig on an uphill grade like it's tied to a post is a far cry from the usual truck crawling up a grade in the slow lane. And Tesla says the Semi's motors develop such stout regen that the truck can get to the bottom of a long grade and still have cool brakes. A safer rig Tesla is known for its ambitious, if overhyped, Autopilot and Full Self Driving, but each of those overlapping driver assistance technologies will find a better home in the Semi than in personal cars because professional drivers simply pay more attention to driving and the ability of their vehicle. Commercial drivers are also subject to vastly deeper training than the rest of us who have a basic driver's license, suggesting they would learn to really exploit Tesla's driver assistance while not overtrusting it. Tesla has yet to detail the driver assistance technologies that will be available on the Semi and how they'll differ from that on their cars. As Pepsi and FritoLay break in the first few examples of the Semi, the wins they're looking for are several: According to Tesla, conventional big rigs are few but vastly over-index on pollution. Tesla Big rigs are just 1% of the vehicles on US roads but account for 20% of vehicle emissions and 36% of all particulate emission, according to Tesla. Range anxiety should not be an issue since these trucks will be used on preplanned routes. Nearly constant vehicle utilization radically accelerates the fuel and maintenance savings delivered by an electric rig, but real-world experience with that is going to be closely watched. A less-known $40,000 federal tax credit is newly available for large electric trucks, with fewer strings attached than with the $7,500 light vehicle credit. Tesla has a form of pixie dust similar to Apple's: It validates sectors by entering them, making the Semi more than just a product launch and something of a category legitimization. That won't happen immediately, however, as Tesla probably won't achieve volume manufacturing of the Semi until a new assembly line in Texas is completed and starts working at full tilt in a year or so. In the process, more technical specs, confirmed pricing and maybe even a few unpleasant surprises will become known.