The limit of sequential exploitation of a river’s hydraulic potential

Hydraulic energy is one of the most important energy sources worldwide, responsible for almost twenty percent of worldwide electricity production. With the objective of collaborating with hydropower energy exploration planning in a watershed, this work provides a procedure for determining the theoretical maximum power limit technically possible from a given flow. The presented procedure can provide more support for the research of potential exploration studies of the optimization of fall partitions in river inventory studies, identify the remaining potential, and support re-powering studies of power plants and the multiple uses of water and can be applied in any watershed of any region from which data are available. The paper is divided in two main parts: first, a review of the basis of theoretical thermodynamic laws applied to determine how to evaluate the maximum hydroelectric potential available in a river, which can be exploited by successive hydropower dams; and second, application of the developed method to three Brazilian small watersheds, where the results are correlated with river characteristics. The theoretical modeling results showed that the maximum limit possible for energy exploitation in a catchment is 50%, based on the flow at the mouth and medium declivity between the nascent and the mouth.