Abstract: An integrated system includes a fuel cell assembly for supplying electrical power to a building, a furnace having a heating chamber and a heat exchanger for supplying heat to the building, and a reformer for providing a supply of reformate directly to the furnace and the fuel cell assembly. The system may include a controller for apportioning the supply of reformate to the fuel cell assembly and to the furnace in response to heating and electrical power needs of the building. In another embodiment, an integrated system includes a fuel cell assembly for providing electrical power to a building, a reformer/furnace unit comprising a chamber and a heat exchanger for providing heat to a building, and wherein fuel is reformed/oxidized in a fuel-rich environment in said chamber to produce a supply of reformate for said fuel cell assembly, and in a fuel-lean environment in said chamber for releasing heat.