TECHNOLOGY FOCUS - COMPUTING AND CONTROL - Preferred Method: The method comprises a third operational mode including mixing first hydrocarbon fuel and air to form a rich combustion mixture, feeding the rich combustion mixture into the thermal combustor, igniting the rich combustion mixture to produce a rich exhaust stream, mixing the exhaust stream with water to produce an air-fuel-steam mixture, feeding the air-fuel-steam mixture into the catalytic combustor, partially reforming the air-fuel-steam mixture in the catalytic combustor to produce a second H2-enriched reformate, feeding the second H2-enriched reformate into the quasi-autothermal reactor to heat reformer tubes, and removing the second H2-enriched reformate from the quasi-autothermal reactor; and a fourth operational mode including mixing first hydrocarbon fuel and air to form a rich combustion mixture, feeding the rich combustion mixture into the thermal combustor, igniting the rich combustion mixture to produce a rich exhaust stream, feeding the rich exhaust stream into the catalytic combustor, reacting the rich exhaust stream to produce a third exhaust that is free of hydrocarbons, feeding the third exhaust into the quasi-autothermal reactor to heat reformer tubes, and removing the third exhaust from the quasi-autothermal reactor.    TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred Components: The apparatus comprises a fuel cell to receive a portion of reformate stream into an anode chamber and a fourth oxygen-containing gas stream into a cathode chamber for the production of electricity; an air-fuel-steam (AFS) mixer (4) having a mixing chamber, a gas inlet for introducing the second oxygen-containing gas into the mixing chamber, a fuel inlet for introducing the third hydrocarbon fuel into the mixing chamber, and a steam inlet for introducing steam into the mixing chamber; and a feed mixture outlet connected with the catalytic reformer for introducing the feed mixture into the catalytic reformer. The air inlet, fuel inlet, steam inlet, and mixing chamber are arranged and designed to promote mixing of second oxygen-containing gas, third hydrocarbon fuel, and steam to produce the gaseous feed mixture. The catalytic reformer comprises a casing having an inlet for receiving the second exhaust stream and an outlet for removing the second exhaust stream, and enclosing reformer tubes arranged in such way that their exterior surface is contacted and warmed by the second exhaust stream. Each reformer tube has a feed mixture inlet for receiving the feed mixture from the AFS mixer, a catalytic region in which the feed mixture contacts the second catalyst to produce the reformate stream, and a reformate outlet for removing the reformate stream from the reformer tube. Each reformer tube comprises a first tube providing the exterior surface, and a second tube arranged within the first tube to define a space. The catalytic region is disposed within an annular space defined between the first and second tubes, or within the second tube.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The first and second oxygen-containing gases are air. The first, second, and third hydrocarbon fuels are identical. The fourth oxygen-containing gas is air.