Electrical interconnection network in an extreme dry weather scenario - the Portuguese case

Portugal and Spain share the same spot energy market (MIBEL), a single price market for both countries, forming a market with greater aggregation that can negotiate energy on the international market with advantages for both countries. The interconnections between Portugal and Spain, and this one with France and Morocco, represent an important role in energy transactions. The adoption of decarbonization goals led in Portugal to the deactivation of all thermal units based on coal-based electricity production. These deactivations, in early 2021, bring challenges to the Portuguese transmission system dispatch operator. Portugal has a production base with a strong hydro component. In a year of extreme dry climatic situation, as in the winter 2022, it is necessary to import and exchange energy at the maximum levels at interconnection points, close to the limits agreed for the year in question, which may place the system in a situation of greater complexity of short-term load dispatch. This paper aims to demonstrate that for these climatic situations of extreme drought, the system can be close to operating in the limits of the interconnection network. This may not represent a fault situation, but it reveals the need for an equation of connection reinforcements between Portugal and Spain, to overcome extreme situations of interruptions that could compromise the stability of the network.