A power generation system (100) and a method of generating power. In one embodiment of the system shown in FIG. 1, a gasification subsystem (1) is configured to convert a carbonaceous fuel to fuel suitable for combustion in a gas turbine (48). A first power generation cycle (2) includes the gas turbine (48) coupled to receive fuel from a gasifier (24). A first Rankine cycle (3) is coupled to receive thermal energy from at least the first power generation cycle (2) and generate power with a first vapor turbine (58). A second Rankine cycle (4) is coupled to receive thermal energy from the gasification subsystem (1) or the first power generation cycle (2) and generate power with a second vapor turbine (82). In an associated method, syngas (26) is generated and processed to remove components therein. Power is generated in a first turbine (48) with the processed syngas (33). Power is generated in a second turbine (58) with heat recovered from exhaust produced by the first turbine (48). Power is generated in a third turbine (82) with heat recovered from the syngas (33).