This article presents the experimental energy efficiency and estimates of CO2 emissions of low-grade power station coals as well as of coal-fired power generation, transmission, and distribution systems. It has been shown that increase in ash and moisture in coal increases the greenhouse emission burden. Simultaneously, increase in the maturity of coal increases its greenhouse index. The sensitivity of the CO2 generation index to the gross electric efficiency, auxiliary power efficiency, and transmission and distribution efficiency is brought out. The variation of the energy efficiency and greenhouse index with plant size is attributed to the fact that the smaller-sized units are old, whereas the bigger units are of recent origin. It has been shown that through planned overhauls, 5-9% reduction in CO2 emission can be achieved, while from renovation and modernization schemes the reduction expected is 17-22%.