What you should also know is that several new co's, including Massachusetts-based Konarka, are perfecting thin-film solar technology to the point where it can be built into fabrics ... like tents. The FOB applications are many, and include not just tents, but essentially any structure, parked vehicle or space that lends itself to being partially or fully covered.
With tents that retain 50% more energy, with micro-grid and energy management systems that save 20-25%, and with tents and other surfaces creating new solar sources of FOB energy, it's plain to see that Army field units, in deserts anyway, may not need fuel convoys much longer. Food and ammo, yes. Fuel, no.
Photo courtesy of Konarka