A rechargeable power system comprising: a drill string configured to operate in a well bore, the drill string comprising: a fuel cell system; a generator in electrical communication with the fuel cell system; a turbine, configured to rotate due to an impingement of drilling mud on one or more turbine blades, the turbine in operable communication with the generator; and where the fuel cell system is configured to provide power at least when drilling mud is not circulating in the well bore, and further configured to be recharged by the generator when drilling mud is circulating in the well bore. A method for operating a rechargeable downhole fuel cell. The method comprises: monitoring a fluid supply pressure; determining whether the fluid supply pressure is below a threshold value; and stopping a fuel cell discharge if the fluid supply pressure is below the threshold value.