A fuel cell system includes a fuel cell stack, which during operation generates electrical energy by reacting a first stream of reactant gas and a second stream of reactant gas. The fuel cell stack also produces a fuel cell exhaust stream. An oxidizer unit is positioned to receive the fuel cell exhaust...http://www.google.fr/patents/US6370878?utm_source=gb-gplus-shareBrevet US6370878 - Recovering heat from fuel cell exhaust
