Abstract: The present invention is concerned with a power generation process and system (10) comprising gasifying (12) a carbonaceous fuel source to yield a synthesis gas (17); cooling the synthesis gas; removing carbon dioxide from die cooled synthesis gas (18), leaving a combustible gas suitable (19) for power generation; compressing (20) the removed carbon dioxide for storage or sequestration; and utilising at least some of the compressed carbon dioxide for the cooling step. A system for implementing the above process, including a suitable valve arrangement, is also provided.