The coal flow rate is essentially a measure of physical plant size. Most CO2 capture systems in the IECM use steam from the steam cycle, which would normally cause the gross electrical output for a given coal flow rate to drop. However, the IECM tries to maintain that value and adjusts the coal flow rate to compensate. This is appropriate for a new plant, but in the case of a retrofit, the physical plant size does not change, and thus the coal flow rate needs to remain the same.