electrochemical cell system . the system includes a low reynolds number microfluidic channel including spaced apart anode and cathode forming sides thereof . a fuel channel introduces a liquid fuel into the microfluidic channel for laminar flow along the anode and an oxidant channel introduces a concentrated liquid oxidant into the microfluidic channel for laminar flow along the cathode . an electrolyte channel introduces a liquid electrolyte into the microfluidic channel for laminar flow between the fuel and oxidant flows . electrodes are connected to the anode and cathode for connection to an external load . in another embodiment , the anode is porous and a gaseous fuel such as hydrogen diffuses through the anode into the interior of the microfluidic channel .