NOVELTY - Separation of synthesis gas stream, generation of electricity from separated hydrogen enriched stream, and sequestration of liquid carbon dioxide (CO2) stream process comprise feeding shifted synthesis gas stream (1) at less than or equal to 50 bar to at least one membrane separator (M-101) provided with membrane; feeding CO2 enriched retentate stream (2) to CO2 condensation plant; passing hydrogen (H2) enriched vapor stream (3) as fuel gas feed stream to combustor(s) of gas turbine(s) of power plant for production of electricity; and sequestering liquid CO2 stream(s).    USE - Method for separating synthesis gas stream into hydrogen enriched vapor stream and liquid carbon dioxide stream, generating electricity from separated H2 enriched stream by feeding separated H2 enriched stream as fuel gas stream to combustor of at least one gas turbine of power plant, and sequestrating liquid carbon dioxide stream (claimed).    ADVANTAGE - The method operates at low temperature of 0-50 degrees C; utilizes refrigeration system which employs single external refrigerant (propane), thus eliminating requirement for ethane and/or ethylene refrigerant; separates all of hydrogen from synthesis gas stream at pressure that is at or above minimum fuel gas feed pressure; and separates at least 90% of carbon dioxide from shifted synthesis gas stream.    DETAILED DESCRIPTION - The separation of synthesis gas stream into H2 enriched vapor stream and liquid CO2 stream, generation of electricity from separated H2 enriched stream by feeding separated H2 enriched stream as fuel gas stream to combustor of at least one gas turbine of power plant, and sequestration of liquid CO2 stream process comprise:    (A) feeding shifted synthesis gas stream at least 50 bar to at least one membrane separator provided with membrane having selectivity for H2 gas over CO2 of greater than 16, and withdrawing from membrane separation unit H2 enriched permeate stream having CO2 content of less than or equal to 10 mol.% and CO2 enriched retentate stream having CO2 content of at least 63 mol.%, where H2 enriched permeate stream (3) and CO2 enriched retentate stream are each withdrawn from membrane separation unit at pressure that is at or above the minimum fuel gas feed pressure for combustor of gas turbine(s) of power plant;    (B) feeding CO2 enriched retentate stream to CO2 condensation plant comprising first cryogenic separation stage and optional cryogenic separation stage(s), where first cryogenic separation stage and optional cryogenic separation stage(s) comprise heat exchanger and separator vessel, and generating in CO2 condensation plant H2 enriched vapor stream having CO2 content of less than or equal to 10 mol.% and at least one liquid stream comprising pure liquid; and    (C) passing H2 enriched vapor stream having CO2 content of less than 10 mol.% and/or H2 enriched permeate stream having CO2 content of less than 10 mol.% as fuel gas feed stream to combustor(s) of gas turbine(s) of power plant for production of electricity; and sequestering liquid CO2 stream(s).    The feeding of CO2 enriched retentate stream to CO2 condensation plant comprises:    (A) passing CO2 enriched retentate stream through heat exchanger of fist cryogenic separation stage where retentate stream is cooled against external refrigerant to below its dew point to form cooled stream comprising liquid phase and vapor phase, where liquid phase comprises pure liquid CO2 and vapor phase is enriched in H2 compared with retentate stream;    (B) passing 2-phase stream (13) to separator vessel of first cryogenic separation stage, where liquid phase is separated from vapor phase;    (C) withdrawing liquid CO2 stream and H2 enriched vapor stream from separator vessel of first cryogenic separation stage;    (D) passing H2 enriched vapor stream through heat exchanger of cryogenic separation stage if CO2 content of H2 enriched vapor stream is above 10 mol.%, where vapor stream is cooled against external refrigerant to below its dew point to form cooled stream comprising liquid phase and vapor phase;    (E) passing 2-phase stream to separator vessel of cryogenic separation stage where liquid phase is separated from the vapor phase;    (F) withdrawing liquid CO2 stream and H2 enriched vapor stream from separator vessel of cryogenic separation stage; and    (G) passing H2 enriched vapor stream through cryogenic separation stage(s) until CO2 content of H2 enriched vapor stream that is withdrawn from separator vessel of cryogenic separation stage is less than or equal to 10 mol.%.    DESCRIPTION OF DRAWING(S) - The drawing is schematic diagram illustrating the membrane separation unit and carbon dioxide condensation plant.    Shifted synthesis gas stream (1)    carbon dioxide enriched retentate stream (2)    hydrogen enriched vapor stream (3)    2-Phase stream (13)    Membrane separator (M-101)