Abstract: The present invention provides a device comprising a first chamber and a second chamber, the first chamber oriented in two alternative ways (1) the first chamber having an anode in contact with an aqueous solution comprising a photosynthetic organism or photosynthetic part thereof and an electron acceptor molecule, an inlet and an outlet, OR (2) the first chamber having direct contact between an anode and the photosynthetic organism, the second chamber having a cathode in contact with an aqueous solution of an electrolyte, an outlet, wherein the anode and the cathode are connected by a switched electric circuit optionally having an external power source and wherein the second chamber is separated from the first chamber by a proton selective membrane. The device described in the present inventions allows for the production of hydrogen and electrical current.