Do you think it's a hassle hauling that spare battery for your laptop? Talk to your friendly neighborhood U.S. infantryman. Armies still march on their stomachs, but nowadays, they also march on their batteries to run their radios, GPS units, night-vision rifle scopes, and other mission-critical electronics. (Surely some officer has an iPad app to call in Predator drone strikes... Angry Birds 2.1.0, right?) A soldier marching out on a 72-hour mission may need twenty pounds of batteries. That's twenty pounds of bullets, grenades, and Spam crowded out of the pack. That's a problem.
Eggheads to the rescue! The Defense Advanced Research Projects Agency is calling for proposals to develop wireless power transmission devices. One possibility DARPA envisions is one rechargeable backpack power unit that would beam juice to all those toys.
They could talk to Intel, which demo'd a wireless power transmission prototype three summers ago. Perhaps they can piggyback with the Aussies, who are developing kinetic energy harvesters to draw juice on the march. Our guys are working on a similar boot-based kinetic charger. I could use that!
The Konarka company is working on camo-pattern plastics and textiles that can catch solar power. Integrate those materials into gear and garments, and G.I. Joe is recharging all day long (I know, I know: what about night vision gear?).
Want to serve your country? You can pump iron, get big, and go chase bad guys in the desert. But you can also hit the books, get that engineering degree, and save thousands of lives (not to mention flat feet) by designing better batteries and power-generation technology.
This is a boondoggle that is periodically explored every 15 years by various ignorant people with money. Wireless transmission is comically inefficient. Also, it's not one of these problems that can be solved by developing new materials or approaches. We have already achieve the maximum theoretical efficiency for these systems. This is just a case where they physics just say no.
Microwave transmission from satellites is being developed. Stace Nelson's military spooks are losing the cyber war: http://www.wired.com/dangerroom/2011/08/problem-from-hell/