Integrated gasification combined cycles (IGCC) exhibit conditions particula
rly favourable to the sequestration of CO2. The concept pursued in this pap
er is the generation of syngas low in carbon, where most of the heating val
ue of the coal fuel is carried by hydrogen. Catalytic shift reactors conver
t most of the CO in the syngas into CO2, which is subsequently removed by p
hysical absorption and then compressed to make it suitable for transport an
d permanent storage. Energy balances, performance, and cost of electricity
are evaluated for two plants based on a Texaco gasifier and a large, heavy-
duty gas turbine giving an overall IGCC power output between 350 and 400 MW
. In one plant, the raw syngas exiting the gasifier is cooled in a high-tem
perature, radiative cooler; in the other it is quenched by the injection of
liquid water With respect to ''conventional'' Texaco IGCCs, the reduction
of specific CO2 emissions by 90 percent reduces LHV efficiency from 5 to 7
percentage points and increases the cost of electricity of about 40 percent
. These penalties can be reduced by accepting lower reductions of CO2 emiss
ions. Compared to the semiclosed cycle considered by other authors, where C
O2 is the main component of the gas turbine working fluid the plants analyz
ed here exhibit higher efficiency over the whole range of specific CO2 emis
sions.