Back in June 2004, DefenseReview reported on the U.S. Army’s development of photovoltaic tech to power U.S. Army tents and even soldiers themselves by integrating lightweight, flexible solar panels with tent and combat uniforms/BDU fabric.  The article was titled, "U.S. Army Develops Lightweight, Flexible Solar Panels to Power Troops", and it contains a host of relevant links to the private companies that manufacture the technology and are involved with the project.