Coal in India

Carbon capture and storageCarbon capture and storage (CCS) could be a key technology in achievingemissions reductions. In the IEA’s 450 Scenario, wind generation wouldneed to increase twenty-fold in the absence of CCS, compared with ten-foldwith the adoption of CCS. Although the technology has been demonstrated,the pace of deployment will need to be accelerated to achieve climate goals(IEA 2014a, 2014b).CCS prevents large amounts of CO 2from being released into theatmosphere. The process involves capturing CO 2from power plants or otherindustrial processes, compressing it for transportation, and injecting it deepinto suitable rock formations, typically at depths greater than one kilometre.The CO 2is captured by separating the CO 2from the flue gas using chemicalsolvents, membranes or changing the operation of the boiler so that the coalis combusted in pure oxygen instead of air. The captured CO 2is typicallytransported to a storage site via pipeline. The CO 2is then injected via deepwells into a porous reservoir rock, such as sandstone, where it flows throughthe rock. To ensure the CO 2remains trapped, geological storage sites arecarefully selected so that there is a thick impermeable cap rock, such asmudstone, above the reservoir rock. This forms a seal and ensures the CO 2remains trapped and cannot escape into the atmosphere. Storage sites aremonitored to ensure the CO 2remains trapped in the reservoir and there is nosignificant impact on groundwater resources, soil or air.Figure 38. Geological storage of carbon dioxideSource: GCCSI 2015a.The identification and development of storage sites can be time consumingand expensive. Further, the installation of CCS technology has beenestimated to increase the cost of a coal-fired plant by 45–75 per cent. CCStechnology also requires large volumes of heat to regenerate solvents andelectricity to operate the pumps and compressors. The extra energy required98COAL IN INDIA 2015