Heck, what's the cost involved to recharge all of those massive batteries in 30 minutes. Electricity is not free. If it costs as much or more than diesel is this a great benefit? If the electricity generated to provide the truck with its "fuel" is generated by a coal fired power plant, is this a great benefit?
I love Tesla and Elon Musk but I think this is a distraction from the problems that he is currently having trying to get the cheap Model X on the road (ultimate fail so far). Now he wants 1000 people to send him 250,000 in deposits for a non-existent sports car as well. Great way to raise money but a terrible way to run a business.