This paper assesses performances and economic viability of CO2 removal by c
hemical absorption from the flue gases of natural gas-fired Combined Cycles
. more specifically for two configurations: one where CO2 is removed ahead
of the stack without modifying the power cycle: the other where part of the
flue gases is recirculated to the gas turbine. thereby reducing the flow t
o be treated by chemical absorption. In both cases sequestered CO2 Is made
available at conditions suitable to storage into deep oceanic waters. Perfo
rmances and cost of electricity are evaluated for systems bused on large. h
eavy-duty turbines representative of state-of-the-art "FA" technology. Carb
on sequestration re duces net plant efficiency and power output by about 10
percent and increases the cost of electricity from 36 to aborts 50 mills/k
Wh, Flue gas recirculation warrants slightly higher efficiencies and lower
costs. CO2 removal is rvenrualh compared with other strategies for the redu
ction of CO2 emissions, like switching existing coal-fired steam plants to
natural gas or replacing existing steam plants with conventional CCs. At cu
rrent fuel prices the latter appears the option of choice, with a cost of a
bout $25 per tonn of avoided CO2 emission.