Impacts of climate change on hydro power production in India

Hydropower is one of the important renewable energy resources in India, which is sensitive to climate change. Future changes and associated uncertainty in streamflow and hydropower potential are examined using simulations from three hydrologic models (HMs) forced by five general circulation models (GCMs) under the four representative concentration pathways (RCP 2.6, 4.5, 6.0 and 8.5). Streamflow is projected to increase marginally during the near period (2010-2039) and by 10.3 and 22.3%, respectively during the mid (2040-2069) and the End periods (2070-2099) with respect to the historic reference period (1971-2000). A higher increase in streamflow is projected under the RCP8.5 scenario than that of the other RCPs. Results show that high flow (90th percentile) is projected to increase while low flow (10 percentile) is projected to decline under the projected future climate. Moreover, streamflow for most of the reservoirs during the inflow season is projected to increase in the mid and End periods of the projected future climate. Projected changes in hydropower potential for major reservoirs are consistent with the changes in streamflow and hydropower potential is projected to increase in the mid and end terms. Hydropower potential in major hydroelectric dams in India is projected to increase by 6.8, 24.7, and 49.5 % during the Near, Mid, and End periods, respectively. Analysis of Variance (ANOVA) was used to estimate certainty in streamflow projections due to HMs, GCMs and RCPs. Results show that climate projections from the GCMs contribute more than 50% in the total uncertainty in streamflow projections. The uncertainty due to interaction between GCMs, HMs and RCPs was estimated separately, which holds a considerable portion in the uncertainty assessment. Results reported in this work have implications for hydropower producing reservoirs in India.