A direct methanol fuel cell (DMFC) system is provided with a pump for pumping methanol into the cell. The pump is driven by carbon dioxide produced by the electro-chemical reaction at the anode of the fuel cell. Because the amount of CO2 generated is proportional to the power generated by the cell, and thus the amount of fuel demanded by the cell, the pump is self-regulating. The system may be integrated using microelectro-mechanical system fabrication techniques.