Their breakthrough is a significant step forward in the effort to equip more cars to run on methane, an abundant fuel that is locally produced and cleaner-burning than petrol. Developed by researchers at the University of Missouri-Columbia and the Midwest Research Institute in Kansas City, the technology has already been incorporated into a test bed on a pickup.

Says principal project leader Peter Pfeifer: “We are very excited about this breakthrough because it may lead to a flat and compact tank that would fit under the floor of a passenger car, similar to current fuel tanks. Such a technology would make natural gas a widely attractive alternative fuel for everyone.”