Abstract
The integration of high shares of variable renewable energy sources is becoming more and more challenging. The main options to achieve this task are the enlargement and reinforcement of the grid, the use of storage devices, and demand-side management. In this work, a multi-nodes modelling approach has been implemented to study the current situation of the Italian electric system. After evaluating the potentialities of variable renewable energy sources such as photovoltaic and wind power in terms of new installation and overall installed power, different scenarios have been developed. The final aim is to compare the single-node to the multi-nodes approach and to study the role of pumped hydro storage system as existing storage solution in Italy. At the increasing of the renewables generation, the results show the benefits in using the multi-nodes more complex methodology compared to the single-node one. Considering the overall potential of Italian variable renewable generation within the system, the single-node model presents an underestimation of the curtailments of about 7% and thus an over-estimation of the percentage of renewables in the system equal to 6.6%. The already installed power of pumped hydro storage allows for a better integration of renewables and highlight its central role in increasing the percentage of renewable electricity consumption.