A wind hydro hybrid system with water storage capacity: Comparison between conventional reservoir and reversible operation

Alexandre Beluco

A wind hydro hybrid system with water storage capacity: Comparison between conventional reservoir and reversible operation

Alexandre Beluco

Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil

: J Nucl Ene Sci Power Generat Technol

Abstract

Hydropower reservoirs (of conventional and pumped storage plants) can provide dispatchable power and large scale energy storage. They can be a suitable technology in autonomous power systems with high levels of energy supplies obtained from renewable energy resources, because of their capacity to buffer intermittencies and high variability of renewables such as wind and solar power. This panel presents a study focused on a wind hydro hybrid system with water capacity storage, both as a conventional reservoir and as a reversible plant. This study compares the hybrid system including a conventional hydropower with a water reservoir with the hybrid system including a pumped storage hydropower plant. This comparative study was carried out based on the adaptation of software Homer (The Micropower Optimization Model), version Legacy, to simulate hydropower plants with conventional reservoir and to simulate pumped storage hydroelectric plants. The case study of this paper arose from data related to the State of Rio Grande do Sul, in southern Brazil. The case study is based on a river basin in southern Brazil for which two sites were identified; one below where can be installed the power house of a hydroelectric plant and where there is a reasonable area to implement a water reservoir; other above where a reservoir may also be implemented to be operated as an upper reservoir for the case of pumped storage hydropower plant. The results show that the system with pumped storage plant naturally has the highest initial costs, but the optimal solution of the hybrid system with pumped storage option require a smaller flooded area (considering the operation of upper and lower reservoirs) than the system with conventional reservoir, thus representing a lower environmental impact. The hybrid system with the pumped storage option also has the lowest cost of energy.