Bummer: Military hasn't been able to produce a safe, reliable, 50,000-pound wind-powered fighting vehicle

Wind energy, a renewable technology that is gaining traction in many parts of the globe, has so far proved unsuited to the battlefield. “We’ve not had a lot of success with tactical wind,” said Colonel Robert Charette Jr., director of the Marine Corps Expeditionary Office.
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Likewise. the military has unique challenges for improving fuel efficiency in the vehicles it uses at war. The weight of battle vehicles has increased sharply in the past decade, largely because heavier armor is needed to protect soldiers from attacks by roadside bombs in Iraq and Afghanistan.

An MRAP (mine-resistant ambush-protected) armored vehicle weighs 50,000 pounds and gets four miles per gallon.