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<p>Carbon Capture and Storage (CCS) technologies provide a means to significantly
reduce carbon emissions from the existing fleet of fossil-fired plants, and hence
can facilitate a gradual transition from conventional to more sustainable sources
of electric power. This is especially relevant for coal plants that have a CO2 emission
rate that is roughly two times higher than that of natural gas plants. Of the different
kinds of CCS technology available, post-combustion amine based CCS is the best developed
and hence more suitable for retrofitting an existing coal plant. The high costs from
operating CCS could be reduced by enabling flexible operation through amine storage
or allowing partial capture of CO2 during high electricity prices. This flexibility
is also found to improve the power plant’s ramp capability, enabling it to offset
the intermittency of renewable power sources. This thesis proposes a solution to problems
associated with two promising technologies for decarbonizing the electric power system:
the high costs of the energy penalty of CCS, and the intermittency and non-dispatchability
of wind power. It explores the economic and technical feasibility of a hybrid system
consisting of a coal plant retrofitted with a post-combustion-amine based CCS system
equipped with the option to perform partial capture or amine storage, and a co-located
wind farm. A techno-economic assessment of the performance of the hybrid system is
carried out both from the perspective of the stakeholders (utility owners, investors,
etc.) as well as that of the power system operator. </p><p>In order to perform the
assessment from the perspective of the facility owners (e.g., electric power utilities,
independent power producers), an optimal design and operating strategy of the hybrid
system is determined for both the amine storage and partial capture configurations.
A linear optimization model is developed to determine the optimal component sizes
for the hybrid system and capture rates while meeting constraints on annual average
emission targets of CO2, and variability of the combined power output. Results indicate
that there are economic benefits of flexible operation relative to conventional CCS,
and demonstrate that the hybrid system could operate as an energy storage system:
providing an effective pathway for wind power integration as well as a mechanism to
mute the variability of intermittent wind power. </p><p>In order to assess the performance
of the hybrid system from the perspective of the system operator, a modified Unit
Commitment/ Economic Dispatch model is built to consider and represent the techno-economic
aspects of operation of the hybrid system within a power grid. The hybrid system is
found to be effective in helping the power system meet an average CO2 emissions limit
equivalent to the CO2 emission rate of a state-of-the-art natural gas plant, and to
reduce power system operation costs and number of instances and magnitude of energy
and reserve scarcity.</p>
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