DEFINITION OF RESERVOIR OPERATION RULE USING SEASONAL WEATHER FORECASTS
Optimization. Operating rules. Precipitation forecasts. Water scarcity. Hedging rules.
Semi-arid regions are characterized by high temporal and spatial variability of precipitation, resulting in high uncertainty in their estimation. This fact has a dramatic impact on the decisions taken to allocate water resources to demand centers, making it difficult to manage water resources. Added to this is the frequent occurrence of drought associated with climate change and global warming, which has made the difficulty of meeting water demands a relevant global problem. The integration of weather forecasting in the management of a hydrological system can substantially improve the safety of the operation. Therefore, this research verified the adequacy of the use of precipitation forecasts in the definition of an operating rule for the Cruzeta reservoir, inserted in the Brazilian semiarid region. Scenarios were developed using a genetic algorithm (GA) to optimize the variables involved in the hedging operation with forecast (FH). This operation had its performance indicators compared to other 4 operations: Standard operating policy (SOP), current hedging rule for the Cruzeta reservoir (C), hedging without predictions (R) and hedging with perfect forecast (PFR). The results showed that the 3 hedging scenarios optimized in GA (R, FR and PFR) presented intermediate results between the consumption of SOP and the conservatism of C. Their results present proposals for reasonable reservoir operations, which make the most of water availability, without letting the reservoir collapse. FR showed improvements in meeting the demands regarding the R rule, including in periods of failure, making more efficient use of storage volume. Still, when comparing FR to PFR, it is clear that the central idea of this work obtained results very close to the idealized condition.