ASSESSMENT OF HYDROPOWER POTENTIAL USING GIS FOR SOUTHERN MIZORAM

Abstract

In this study, Geographical Information System (GIS), Remote Sensing (RS) and the i SWAT i (Soil and Water Assessment Tool) model are used for assessment of hydrop wer potential sites in the Mat watershed, Mizoram, India. The stream network was generated using Are SWAT model. After locating the required elevation for the Digital Elevation Model (DEM), the stream length'was measured from the outlet to check for the distance criteria. The subbasin outlet was then added manually in the stream network at each identified sites and the subwatershed was delineated again. The site was selected as potential hydropower site when both the height and distance criteria are met. The remaining sites were assessed in the same manner starting from the last selected site till the stream ends. Calibration of the SWAT model was done for the year 1988 by manually adjusting the model parameters within the prescribed range and simulated discharge was compared with thie observed discharge. The calibrated model was validated using four established indices, the Coefficient of determination (R2), Nash and Sutcliffe efficiency (NSE), index of agreement (d), and relative error of the stream flow volume ,(RE) for the year 1989, 1991 and 1994. The validation was carried out using the discharge data of the year 198.8, 1989, 1991 and 1994 altogether; and separately for the dry and rainy periods. The discharge at each selected potential sites were generated with the help of the calibrated SWAT model. The hydropower potential was estimated for different discharge dependability using Flow duration Curve (FDC). Thirty three hydropower potential sites are identified within 147.325 km2 of the Mat river basin. A total of 3039.47 KW, 1127.16 KW and 804.98 KW can be harnessed at 50 %, 75 % and 90% dependability respectively. The study revealed that hydropower potential site can be effectively evaluated by analyzing the Digital Elevation Model (DEM), stream network and the SWAT model.