Power generation systems and methods utilizing cascaded fuel cells

A power generation system, comprising:

• a first solid-oxide fuel cell configured to generate a first anode tail gas stream and a first cathode tail gas stream;
• (ii) at least one fuel reformer located downstream of the first solid-oxide fuel cell, the fuel reformer configured to receive the first anode tail gas stream, and to mix the first anode tail gas stream with a reformer fuel stream to form a reformed stream;
• (iii) a splitting mechanism to split the reformed stream into a first portion and a second portion;
• (iv) a fuel path configured to circulate the first portion to an anode inlet of the first solid-oxide fuel cell, such that the first solid-oxide fuel cell is configured to generate a first electric power, at least in part, by using the first portion as a fuel;
• (v) a second solid-oxide fuel cell configured to receive the second portion, and to generate a second electric power, at least in part, by using the second portion as a fuel, the second solid-oxide fuel cell further configured to generate a second anode tail gas stream and a second cathode tail gas stream;
• (vi) a first recuperator configured to receive and extract heat from at least a portion of the first cathode tail gas stream and the second cathode tail gas stream to form a cooled cathode tail gas stream, and to transfer at least a portion of the extracted heat to the first portion of the reformed stream;
• (vii) a recycle loop extending from an outlet of the first recuperator to a cathode inlet of the first solid-oxide fuel cell, wherein the recycle loop is configured to circulate at least a portion of the cooled cathode tail gas stream to the cathode inlet of the first solid-oxide fuel cell;
• and
• (viii) an air pre-heater configured to extract heat from at least another portion of the cooled cathode tail gas stream directed via a channel coupled to the recycle loop, and to transfer at least a portion of the extracted heat to a cathode inlet stream of the first solid-oxide fuel cell, wherein the recycle loop extends from the first recuperator to the first solid-oxide fuel cell bypassing the air pre-heater.