Global warming by greenhouse gases (GHG) has become a major concern worldwide due to its adverse effect on climate change. With the growing energy demand, fossil fuel consumption has increased and this is leading to enormous carbon dioxide (CO2) emissions. Countries such as China, United States of America and the European Union are the leading CO2 emitters in the world, while the developing countries like India also contribute to a significant amount of global CO2 emissions. Figure 1.1 shows the share of global CO2 emissions by different countries from fossil fuels during the year 2010 to 2018 [1,2]. India ranks 4th after China, United States and the European Union with 7.26% share of global CO2 emissions during the year 2018. In the recent years, notable decrease in global share of CO2 emissions can be observed in case of United States and European Union due to good CO2 management. In case of China, Russia and Japan, the share of emissions is stable, whereas it is on the increase for India due to increased power production. For countries like India, the problem of CO2 emission is more critical as 55% of electricity is generated from coal [3] as on November 2020 because of its vast coal resources, amounting to 8.3% of global reserves [4] To meet the global commitments on emissions, India is planning for a judicial mix of coal, renewables and nuclear. The low calorific value (or high- ash content) in Indian coal reduces the net efficiency of the power plant as compared to low ash content (or high calorific value) coals [5].