Optimization Model of Reservoir Operating Pattern Based on the Adaptive Inflow for Climate Change

Abstract

Urban Climate change in the past 40 years carries significant effects on the earth's surface. It shows an effect of extremely anomaly temperature because of such phenomenons as ENSO, IOD, and SOI. Thus, it can lead to seasonal change in Indonesia that affects the reservoir inflow and impacts the reservoir's operation pattern for managing power plant, irrigation, and raw water supply. This research used the relation between SST data (Nino 1.2, Nino 3, Nino 3.4, Nino 4, IOD West, IOD East, and SOI index) from NOAA and rainfall data from 1998 to 2018 in 9 stations at Wonogiri Reservoir Watershed from BBWS Bengawan Solo. With multiple linear regression analysis with a stepwise regression method, it indicated that the rainfall at Wonogiri Watershed and Inflow at Wonogiri reservoir was influenced by the SST index (Nino 1.2, Nino 3, Nino 3.4, Nino 4). Meanwhile, during the dry season, the rainfall at Wonogiri Watershed and the Inflow at Wonogiri reservoir were influenced by the SST index (IOD West, IOD East, and SOI). The rainfall and SST are related to being modeled for the probability of inflow distribution in each period (every 15 days). This inflow model influenced by climate change is to be used for the optimization model of reservoir operating pattern with Stochastic Model. The result that scenario 6 have the highest benefit, highest performance in the reliability and resiliency value in the simulation for a period between years 1979-2018.