Global warming due to the accumulation of atmospheric CO 2 has received widespread attention in recent years. Although various CO 2 capture technologies have been proposed, using the captured CO 2 from power plants is increasingly popular because of concerns with regard to the safety of underground and ocean CO 2 storage. Various techniques related to utilization of CO 2 from the exhausted gas of power plants are discussed in this article. The existing and under-development technologies for CO

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... utilization in the world are briefly reviewed. Two categories, direct utilization of CO 2 and conversion of CO 2 to chemicals and energy products, are used to classify different forms of CO 2 utilization. Regarding the direct utilization of CO 2 , in addition to its use in soft drinks, welding, foaming, and propellants, as well as the use of supercritical CO 2 as a solvent, CO 2 capture via photosynthesis to directly fix carbon into microalgae has also attracted the attention of researchers. The conversion of CO 2 into chemicals and energy products via this approach is a promising way to not only reduce the CO 2 emissions, but also generate more economic value. Since CO 2 is just a source of carbon without hydrogen, a clean, sustainable and cheap source of hydrogen should be developed. This article reviews the literature on the production of biofuel from microalgae cultivated using captured CO 2 , the conversion of CO 2 with hydrogen to chemicals and energy products, and sustainable and clean sources of hydrogen, in order to demonstrate the potential of CO 2 utilization.