Horizontal fuel cell tube system and methods

In one disclosed embodiment according to the invention, a fuel cell system for generating electrical power comprises: an open-ended tubular solid oxide fuel cell; a first fuel injector tube extending from a first fuel plenum chamber through one open end of the fuel cell; and a second fuel injector tube extending from a second fuel plenum chamber through another open end of the fuel cell; wherein the first and second fuel injector tubes form a gap within the fuel cell from which a hydrogen-containing fuel gas may flow towards the open ends of the fuel cell. Further related systems and method are also disclosed.