A fuel cell device comprising: (a) a catalytic oxidiser; (b) means for delivering gaseous fuel and oxidiser to the catalytic oxidiser; and (c) a fuel cell assembly located in the vicinity of the catalytic oxidiser such that the fuel cell assembly is able to be heated by heat generated from the reaction of fuel and oxidiser at the catalytic oxidiser; wherein the fuel cell assembly causes the generation of hot gases and an electrical output when it is heated and supplied with fuel and oxidiser, and wherein the device is provided with (d) a heat outlet which allows hot gases generated by the device to be directed out of the device and to applications requiring heat. Also provided is the use of such a device to generate heat and/or electrical power, and an appliance comprising such a device.