ABSTRACT

In this paper, CO₂ control technologies like decarbonization either of the flue gas or of the fuel, as well as the use of oxyfuels in near zero emission cycles are investigated. Among four existing technologies of CO₂ removal from flue gas- namely, chemical absorption using amines, membranes, cryogenic distillation and selective adsorption on solids-chemical absorption is the most mature and the best suited to power plants and is analyzed from the point of view of its penalties on performance and costs of fossil fuel-fired power plants. The overcost of its generated kWh is around 60%. Decarbonization of the fuel is also considered; it is much less penalizing than chemical absorption and produces hydrogen. A new concept of near zero CO₂ emission power plants is presented, the so-called MATIANT cycle, using an oxyfuel with total CO₂ recycling. The cost of its kWh is 50% to 100% higher than that of a Combined Cycle.
In conclusion, when the external costs are internalized, the resulting social cost (generation + external costs) of the generated kWh in fossil fuel-fired plants with capture and sequestration of CO₂, as well as in MATIANT cycles, is in the range of the social costs of windmills and, for a MATIANT cycle, is comparable to that of a Combined Cycle with capture and storage of CO₂.