If we generate too much energy now, no water is left for future use. If we save too much water now, no energy is generated for present use. How to manage hydropower plant reservoirs in an optimal way?
A tool for optimal reservoir management. The best for maximum energy generation is to store water downstream, keeping a higher water head where there is more water flow. A quite non intuitive result.
The following figure depicts the optimal volume for 2 hydropower plants in series (Três Marias upstream and Sobradinho downstream) along 4 years of operation, where Sobradinho plant stays almost all the time full while Três Marias oscillates according to rain seasonality.