For any nation, sector-wise forecasts of energy demand and emissions are becoming valuable elements in devising its national and international policies relating to energy security, local environment, and global climate change. It is in this context that this work attempts to forecast India's possible energy demands and emissions adopting a key indicator approach on least cost generation expansion optimization methodology for a long time frame. This study developed key indicators for useful-energy demand for end-use sectors such as industry, commerce, and residence. Key indicators for transport sector and non-energy use sectors were developed on transport mobility demand and end-use fuel demand. The main drivers of these key indicators are socio-economic parameters. This work was conducted in a linear programmed (LP) TIMES G5 model on TIMES modeling framework for model horizon of 1990-2100. By the end of the 21st-century, India's energy demands are projected to be about 1825Â Mtoe of primary energy, 1263Â Mtoe of final energy consumption, 4840Â TWh of electricity generations, 723Â Mtoe of energy import, and 4414Â Mt of CO2 emissions.