The Defense Advanced Research Projects Agency (DARPA) announced last Wednesday that it wants to build a short-range wireless power transmission system for troops in the field. According to the General Services Administration, the U.S. Marine Corps and U.S. Army have determined that the increased use of critical portable electronics on the battlefield has led to an increase in the number and types of batteries soldiers are required to carry for essential electronics equipment, such as communications, positioning and targeting. And to maintain functionality of critical gear, soldiers on single-day missions may carry anywhere from five to 10 pounds of batteries. One possible implementation of the system is to have a high-energy fuel cell or rechargeable battery mounted to the soldier’s pack or vest, and to have the power produced by that centralized energy source wirelessly transmitted to the various electronics equipment the soldier carries. If the wireless power transmission system works, it would allow troops to charge up things like GPS wirelessly at a distance of up to about 6.5 feet.