The best mitigation measure to reduce atmospheric carbon will be promotion of green energy and increment of forest cover. However, Hydro-power development a source of cost-effective and low-carbon renewable energy adopted about 160 countries with capacity of 1209 GWe generates about 3500TWh per year along in Asia with 542GW installed capacity and 2,204 GW potential. Does promotion of hydro power development can contribute to reduce GHG or CO2 emission in the atmosphere than another green energy promoting technology ?