Yes--the carbon monoxide is itself a fuel. Burning it with more oxygen converts it to carbon dioxide, and the energy from it can be "harvested" to fed back as steam or electricity to help drive the conversion process. Some fuel cells will run directly on gasification syngas---converting both the carbon monoxide AND the hydrogen into electricity.
How big will the fuel cells be? We are talking about burning coal, saparating CO and H2, burning CO and combining H2 with O2.