A methane-oxygen fuel cell can easily be operated as a methane-air fuel cell, with only a modest reduction in power output. With methane being the primary constituent of natural gas it is clear that a fuel cell that can use this readily available fuel directly will have significant advantages over one that requires reforming the methane before supplying it to the fuel cell. A direct system will be simpler (no reformer), and more efficient. The ability to use natural gas opens up the wide world of distributed generation systems, currently a growing part of the smart grid, and presents a potentially very large commercial market. Fueled with compressed natural gas, these fuel cells are also suitable as electrical power supplies for operation in remote locations. The direct application of this technology is supporting a manned mission to Mars (and poten-tially to other locations where methane can be obtained at later dates). Additional applications include fuel cell power systems for either stationary or flight use. Methane is more easily lique-fied and stored than hydrogen, giving it significant storage and handling advantages. In addition, as noted below as a commercial opportunity, these fuel cells can be operated on natural gas, making them an excellent candidate for use by NASA in distributed generation systems and for electric power at remote locations.