Water Conflicts in Hydrothermal System Operation: The São Francisco River, Brazil

Abstract

There are many conflicts involved in the operation of a hydrothermal system mainly due to competitive uses of water. That is the case of Sao Francisco River located in the northeast region in Brazil. The hydro system in this region has an installed capacity of 10.7 GW and supports 13% of the Brazilian hydro electrical power. Due to the scarcity of water in this region the operation of this system has been questioned in the last few years. The competitive uses of water in this region are water supply, irrigation, animal raising and environmental protection. These demands can be attended by a proposed large water transfer system from Sao Francisco river to other watersheds in the region. The electrical sector is planning to review the reservoir operation rules in order to attend these demands. This paper presents results from a study conducted to evaluate the impacts of the hydro production caused by the multipurpose uses of water in the Sao Francisco River. The study was conducted by applying the HIDROTERM model, which is an optimization model that maximizes hydropower production and minimizes thermo production based on fossil fuels. A new objective function was added to the HIDROTERM model in order to evaluate the proposed water transfer system. The trade-offs among energy, water supply, irrigation and environment protection are presented, along with other relevant discussions.