In a power generation facility (10) a fluidized bed combustion unit (12) produces steam to power a steam turbine generator (32), and a heat recovery steam generator (20) produces steam for the steam turbine generator. Electrical power from the steam turbine generator is conducted to a motor (40) that drives and air compressor (36). The air compressor provides pressurized air back to the fluidized bed combustion unit (12) to promote fuel combustion. Flue gas from the heat recovery steam generator is selectively conducted to a CO2 capture unit (18) and then to a gas expander (42) that assists the motor in driving the air compressor (36). A heat exchanger (46) that is upstream of the CO2 capture unit and a heat exchanger (56) that is downstream of the CO2 capture unit and upstream of the air expander have thermal fluid sides that are connected in a closed circuit. The heat exchangers (46 and 56) convey heat away from the CO2 capture unit and provide heat to flue gas flowing to the gas expander to avoid icing conditions in the gas expander and acid condensation in the air emission stack.