Patent ID: 7732076

Claim:
A solid oxide fuel cell system comprising: (a) at least one tubular solid oxide fuel cell comprising a ceramic solid state electrolyte layer and inner and outer electrode layers concentrically arranged around and sandwiching the electrolyte layer, the inner electrode layer fluidly communicable with only one of an oxidant reactant and a fuel reactant, and the outer electrode layer fluidly communicable with only the other of the oxidant and fuel reactants; and (b) a combustion heater fluidly communicable with the oxidant and fuel reactants such that combustion can occur, the heater mounted in sufficient thermal proximity to the fuel cell that the fuel cell can be heated by the combustion to an operating temperature, the heater comprising a porous outer tube and a porous inner tube within the outer tube, an inside of the inner tube defining an inner combustion chamber fluidly communicable with the oxidant and fuel reactants which form a mixture therein, and an annular space between the inner and outer tubes defining an outer combustion chamber in which fuel and oxidant mixture radially permeating through the inner tube is combusted, the outer tube sufficiently porous to enable the fuel and air reactants to pass through the outer tube.