Cummins unveils an electric big rig weeks before Tesla

Sorry, Tesla, but someone just stole the thunder from the electric big rig you were planning to unveil this fall. The engine giant Cummins has unveiled a concept semi truck, the AEOS, that runs entirely on the power of an electric motor and a 140kWh battery pack. It's roughly as powerful as a 12-liter fossil fuel engine and could haul 44,000 pounds of cargo, just without the emissions or rampant fuel costs of a conventional truck. There's speedy 1-hour charging, and Cummins is even looking at solar panels on the trailer to extend range. It's a promising offering, although Elon Musk and crew might not lose too much sleep knowing the limitations.

For one thing, range is a sore point. You're looking at a modest 100-mile range with that 140kWh pack. That's fine for inter-city deliveries, but it won't cut the mustard for longer trips. And while there's talk of extending that distance to 300 miles with extra packs, that would only make it competitive with Tesla's anticipated 200- to 300-mile range.

And more importantly, this is a concept, not a production vehicle ready to roll off the manufacturing line. There should be a production model in a couple of years, according to CNET, but that gives Tesla plenty of time to get its own EV semi on the road. Not that we're going to complain about both companies having a fighting chance — more electric big rigs means more competition and fewer polluting trucks.