Fighting green

The military's new push to free itself from oil extends from changes in the routines of military life to research in speculative technologies. A few examples:

Alternative power plants. Several military installations already run on renewable energy. China Lake Naval Air Weapons Station in the Mojave Desert has two geothermal plants that generate power from heat deep in the ground. Nellis Air Force Base, outside Las Vegas, recently broke ground on what the Air Force claims will be the country's largest solar array. Texas's Dyess Air Force Base generates its electricity from wind power, and plans to build a waste-to-energy power plant this year.

Fighter fuel efficiency. The Air Force is investigating ways to cut fuel use by stripping excess parts and modifying wing-tip design to make planes more efficient, having them towed out to the runway by hybrid or fuel cell vehicles and limiting the amount of time they spend idling before takeoff.

Hybrid generators. By this summer, the Army plans to field mobile hybrid power generators for units in the field in Iraq and Afghanistan to cut down on the number of fuel convoys that have to run the gauntlet of insurgent attacks to and from bases. The generators will feature solar panels, wind turbines, highly efficient diesel generators, and storage batteries.

Space-based solar. DARPA has shown interest in a proposal from Northrop Grumman to deploy satellites that would gather solar energy from space, and then beam energy to earth using low-power microwaves.