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Traditional technologies of carbon capture and storage (CCS) are being focused on capturing CO 2 in large-scale demonstrations, which has been proved to result in the high cost and energy penalty. Meanwhile, typical innovative measures, commonly defined as the second generation CCS technologies, elude conventional ones by integrating with solar energy and thus contributing to a more energy-efficient conversion of CO 2 . However, few reviews pay attention to thermodynamic processes and parameters of these novel technologies, and there is a lack of systematic evaluation and comparison among them. This paper firstly presents a guided tour on the state-of-art of typical and innovative CCS technologies integrated with solar energy. An overview on thermodynamic processes, including chemical reactions, operating conditions and efficiency indexes of five typical technologies is presented so that the current development level can be clarified. Since the high energy requirement and related operating cost are the main barriers to the application of existing CCS technologies, the minimum work and second-law efficiency are applied as the main indicators in the second part of this paper which relates to performance evaluation. In addition, the performance windows for innovative technologies are illustrated for the comparison of technological maturity. The results show that energy requirement of innovative CCS technologies from the flue gas is avg. 100–200 kJ/mol CO 2 and the second-law efficiency of them is only 5–12%. Therefore, the maturity and popularity of these novel technologies are still relatively low. But the well-integrated systems and diversified output of these technologies can benefit existing energy infrastructures in a long period. [ABSTRACT FROM AUTHOR]

Thermal power plants in India emit around 500 Mt of CO 2 annually. All of it is released into the atmosphere untreated. Microalgae, a third generation feedstock for bio-fuel emerges as a viable option for partly sequestering the emissions. Moreover, its carbon capture capacity of 4.8 kg CO 2 /kg biomass, which is very much as compared to terrestrial substitutes like Jhatropa curcas , enables to produce bio fuel hence adding value to the entire process. This paper intends to build upon this idea and come up with strategies to integrate bio fuel production and CO 2 sequestration with the existing thermal power plants. The raw materials needed for algal growth are available in the plant as elaborated in the paper. Thus the bio fuel produced can be routed back to power the plant consequently lowering the dependence on coal. This would help in putting a check on the carbon emissions thus making the existing systems more environmentally benign and suitable for long haul. This paper reviews currently employed carbon capture technologies and methods and comes up with a strategy to subsume carbon capture through microalgae with power plants of a certain capacity. 3 t/day is taken as the basis for calculations in the proposed flow sheet. An alternative of the above is also provided which substitutes the biofuel production with co-firing. This escalates the nitrogen content of flue gas but deescalates the investment. This brings down the capital investment in the plant but enhances N 2 content of flue gas. Carbon leakage is accounted for in a table of atomic balance. It takes care of input and output of carbon. The paper is inclined towards the conclusion that the Microalgae possess incredible potential and if tapped efficaciously could prove to be extremely helpful in these days of power and environmental crisis. [ABSTRACT FROM AUTHOR]