Six words grab John Perkins’ attention whenever he sees a presentation from the Advanced Research Projects Agency-Energy: “If it works, will it matter?”   “On that slide, ‘will it matter?’ is in a much bigger font than ‘if it works,’” said Perkins, the National Renewable Energy Laboratory’s laboratory program manager for the 10-year-old agency (ARPA-E). “The point of that is they are willing to fund things that are technologically very risky—where it’s unclear as to whether or not you can ac...