Direct carbon fuel cells in which carbon is electrochemically gasified into carbon monoxide offer large thermodynamic advantages. Because the entropy change in this reaction is positive, the theoretical reversible efficiency of a direct carbon fuel cell can be greater than 100%. It means that heat is subtracted from the environment and directly converted into electric power. Hence in contrast with general belief heat can be converted into power with an efficiency greater than the Carnot efficiency. Also the enthalpy of the gasification reaction is directly converted into power whereas in present gasifiers this enthalpy is converted into heat.
These are the driving forces for developing direct carbon fuel cells. Molten carbonate offers good possibilities for the construction of these fuel cell but also YSZ the electrolyte of a SOFC is proposed. Possibly a combination of both in which molten carbonate provides additional reaction paths is possible as well.
On short term the prospects of integrating an MCFC or SOFC with a molten carbonate gasifier looks very promising