Impact of intermittent generation on the expansion of the Spanish power system interconnection capacity

The expected massive penetration of renewable energy sources (RES) in Spain, added to its limited electricity interconnection capacity, will demand not only the introduction of flexible resources in the Spanish power system but also a stronger transmission capacity between this country and Europe. In this context, this paper computes the economic additional interconnection capacity between Spain and Central Europe based on the trade-off between transmission capacity cost and RES spillage cost. For this purpose, a model that simulates the hourly operation of the Spanish power system for a period of one year is used to compute hourly spillage. This analysis covers the period of 2020-2050 and includes four scenarios of RES penetration. In addition, a sensitivity analysis in relation to the cost parameters is presented.