Himalayan Run-Off River Power Generation Modelling for Power Security in Evolving Weather Conditions

Abstract

Extreme black-swan occurrences like earthquakes, glacial lake outbursts, flash floods, landslides, etc. are important concerns in Himalayan countries like Nepal, which are highly susceptible, geologically active, and exquisitely fragile. Nepal generates 97 percent of its electricity from hydropower, where 56.08 percent of it is coming from seasonal run-off-river (RoR) hydro plants. Landslides and mudflows are common in the monsoon, and low discharge is common in the winter season. These RoR plants must be able to withstand high-impact events like earthquakes and lengthy droughts in order for the Nepalese grid to remain secure. This study gives a presentation and overview of previously occured natural hazards in Nepal related to hydropower plants. In particular, the 2014 Sunkoshi landslide and the 2021 Melamchi flood are evaluated as extreme events and their impacts on hydropower plant has been studied. In addition, an in-depth investigation on a ROR plant is carried out. Moreover, the water discharge and extreme rainfall peaks in time series data is evaluated using an ARIMA-based model. This paper shows the feasibility of predicting the energy produced by a run-off river hydropower plant. The purpose is to forecast discharge and hence the ROR power generation with the aim to facilitate the hydropower operators for their availability declaration which will again help in the overall energy planning. The results are discussed together with performance metrics, and indicates that the implemented technique is promising.These predictions can be further used for planning and estimating the power generation on a more complex level.