A method including introducing a carbonaceous feedstock and a heated heat transfer material into a gasifier, whereby at least a portion of the carbonaceous material is pyrolyzed; removing a gasification product gas comprising, entrained therein, char, particulate heat transfer material, and optionally unreacted carbonaceous feedstock; separating a solids product comprising char, heat transfer material and optionally unreacted carbonaceous material from the gasification product gas; heating at least a portion of the solids product via a combustor, thus producing a heated portion of the solids product and a combustor flue gas, wherein a portion of the heat for heating is obtained via combustion of the char; separating the heated portion from the flue gas, and introducing the separated heated portion into the gasifier, providing heat for pyrolysis; and utilizing at least a portion of the gasification product gas for Fischer-Tropsch synthesis and/or power production.