Integration of solar energy with post-combustion carbon capture

Background: A techno-economic analysis has been performed for a coal-fired power plant retrofitted with solvent-based post-combustion carbon capture (PCC) technology where thermal energy is partially supplied by solar thermal collectors. The plant is compared with a generic PCC plant where all the thermal energy is provided by steam bled from the steam cycle. A suite of solar thermal collectors which include flat plate collectors, compound parabolic collectors, linear Fresnel collectors, evacuated tube collectors (ETCs) and parabolic trough collectors (PTCs) have each been tested for their viability. The plant has been simulated for several different locations in Australia: Sydney, Townsville and Melbourne. Objectives: This study investigates the integration of solar thermal energy in the energy mix of a power plant by using it to partially compensate for the debilitating energy penalty burdened by the introduction of the carbon capture process. Methods: The overall system consists of three subsystems: power plant, PCC plant and solar collector field. A base case scenario is studied in which there is no heat integration between the three subsystems and is compared to a system with heat integration. Additionally, incentives such as renewable energy certificates (RECs), carbon tax/credits and government subsidies have been considered in the economic model and a sensitivity analysis has been performed for each scenario of incentives for all five solar collector technologies at the three locations. Results: The ETC is found to be the best performer amongst solar collectors when the three subsystems have good heat integration while the PTC is the best performer in the case of no heat integration. The best location for the solar-assisted PCC (SPCC) plant is found to be Sydney. Conclusions: The SPCC plant is only economically viable in Sydney and Townsville once incentives such as RECs, carbon tax and subsidies are taken into account. By the use of solar energy and the available government incentives for their deployment, the cost of carbon capture is shown to be reduced.