Contribution of non-conventional pumpedstorage hydropower plant configurations in an isolated power system with an increasing share of renewable energy

Abstract

This paper analyses the contribution of non-conventional pumped-storage hydropower plant (PSHP) configurations like variable-speed pumping and hydraulic short-circuit, to reducing the scheduling cost and wind curtailment of an isolated power system with a high penetration of renewable energy. Their impact on the system's CO2 emissions and generation mix is analysed as well. For this purpose, the next-day generation scheduling of the power system of the Great Canary island is computed on a rolling horizon basis for an entire year, considering conventional and non-conventional PSHP configurations and an increasing installed wind power. Different types of start-ups of the thermal generating units and the opportunity cost of water (water value) are considered in the day-ahead generation scheduling. The water value is daily updated by using a two-stage stochastic optimisation model with a two-week planning horizon. The results obtained show how these non-conventional pumped-storage hydropower plant configurations help not only to reduce the power system scheduling cost but also to integrate more wind energy.