The impact of land use land cover change on hydropower potential in northern Ethiopia

Hydropower is the primary source of electric energy in Ethiopia. However, it is dependent on hydrology and sensitive to land use land cover (LULC) changes. However, little has been done to examine the potential impacts on hydropower from LULC changes. The objective of this study is to understand the impact of LULC change on hydropower potential of upper Geba catchment in northern Ethiopia. The LULC change analysis result revealed that croplands and urban areas significantly expanded from 49.5% and 0.9% in 2000 to 60.0% and 4.9% in 2018, respectively. In contrast, shrublands and grasslands constituted 39.7% and 8.2% in 2000 shriveled to 28.7% and 0.7% in 2018, respectively. Prediction of streamflow required for hydropower potential computation was performed with the Water and Energy Transfer between Soil, Plants, and Atmosphere (WetSpa) model. The WetSpa model performed very well for both the calibration period from 1997 to 2008 and validation periods from 2009 to 2014 with results in Nash–Sutcliffe coefficients (NSE) values of 0.86 and 0.80 and model confidence values of 0.82 and 0.76, respectively. The result indicated that the mean daily streamflow in 2018 has increased by 19% compared to that of 2000. Hence, the output is found applicable for the prediction of hydropower. The study evidenced that the hydropower potential of the upper Geba catchment has significantly increased between 2000 and 2018 at an average rate of 167.3 kW, 57.8 kW, and 20.5 kW per year for 50%, 75%, and 90% dependency levels, respectively. Hence, it can be concluded that the LULC change in the upper Geba catchment has significantly increased the hydropower potential. Hence, it is recommended that the planning and operation of hydropower plants in Ethiopia shall consider the impacts of the changing LULC.