The adoption of Renewable Energy Sources (RES) in small and isolated power systems, poses several integration challenges, resulting most times in the necessity of reducing the RES to preserve the stability of the network. This has adverse consequences for the environment, as the replacement is assured by fuel-fired pollutant power stations. As alternative, the RES variability can be compensated with storage systems, in particular Water Pumped Storage Systems (WPSS), which are particularly relevant in island contexts.
In this article, A. Setas Lopes, Rui Castro and Carlos S. Silva, propose a new approach to help the decision-making processes of designing WPPS, using a model that couples the energy balance model and the economic model. Results show that the input with most impact in the Net Present Value of the projects is the wind energy availability. It is important to mention also the impact of the uncertainty of Capital Expenditure which, when increases 50% combined with a project reduced lifetime, may lead to a negative NPV.
This model can be adapted to study WPSS on similar power systems, contributing to a preliminary assessment of the technical and economic viability of this type of systems.