ABSTRACT
Climate change is one of the great challenges of the 21st century [1]. The International Energy Agency (IEA) report of 2011 projected that renewables based electricity generation would triple between 2008 and 2035 under the increasing-use-of-renewables scenario. Hydropower generation makes a substantial contribution to meeting today’s increasing world electricity demands. The report adds that the share of renewables in global electricity generation increases from 19% to almost a third (nearly the same as coal). The primary increase is said to come from hydropower and wind but hydropower remains dominant over the projection period. It is projected that global hydropower generation might grow by nearly 75% from year 2008 to year 2050 under business-as-usual scenario but that
it could grow by roughly 85% over the same period in a scenario with aggressive action to reduce greenhouse gas (GHG) emissions. However, even under this latter scenario, increased hydropower generation is projected to provide only about 2% of the total GHG emission reductions from the global electric power sector compared to business-as-usual by year 2050 (with all renewable technologies nonetheless providing nearly 33.5% of GHG abatement from the power sector). According to IEA, a realistic potential for global hydropower is 2 to 3 times higher than the current generation, with most remaining development potential existing in Africa, Asia, and Latin America. IEA also notes that, while run-of-river (smaller) hydropower plants could provide as much as 150 to 200 GW of new generating capacity worldwide, only 5% of the world’s small-scale (i.e., small, low, and hydro) hydropower potential has been exploited [2].
