Patent ID: 8129057

Claim:
A method comprising: operating a first fuel cell, the operation of the first fuel cell producing a first effluent flow; routing the first effluent flow through an electrochemical pump to extract fuel from the first effluent flow; providing the extracted fuel to the first fuel cell; and wherein routing the first effluent flow through the electrochemical pump comprises: providing the first effluent flow to a second anode chamber of a second fuel cell in a first stage of a plurality of cascaded stages and applying power to the second fuel cell to cause the second fuel cell to produce hydrogen in a second cathode chamber of the second fuel cell in response to the first effluent flow; providing a second effluent flow from the second fuel cell to a third anode chamber of a third fuel cell in a second stage of the plurality of cascaded stages and applying power to the third fuel cell to cause the third fuel cell to produce hydrogen in a third cathode chamber of the third fuel cell in response to the second effluent flow.