DSO - TSO Coordination

Abstract

Distributed energy resources (DER) are bringing connection problems, generation uncertainty, bidirectional flows... However, they may also provide services to the system operators. Improvements of information and communication technologies (ICT) are bringing new possibilities for the monitoring of the low voltage grid levels. In this thesis it will be studied how DER and ICT affects to the European system operators roles. It has been identified the roles, objectives and tools that system operators (DSO and TSO) have nowadays and which ones they will have in the future. In future, roles will remain but DER will bring new tools that will be useful for both DSO and TSO. Since both system operators (SOs) are willing to act over DER, it is necessary to establish coordination so that both SO are be able to use DER services increasing the efficiency of the system: it is necessary to decide who is going to act over DER and how the other SO will be able to consider DER services. In order to solve this coordination issue, it has been proposed a methodology that analyses how different coordination models fit in a country. The methodology is based on three different steps: 1. Analysis of current country boundary conditions 2. Evaluation of the transition costs if this model is implemented using technical, regulatory and economical approaches 3. Assessment of the decision variables for the long term looking at the whole country. In order to see the robustness of the methodology it has been applied the methodology for 3 different models in three different countries. The three countries considered for this master thesis are three different representative countries after studding 12 European countries .Then, it has been applied the methodology nine times: one per each one of the couples country-model that this master thesis consider in order to study the European representative countries. The different models that have been considered are based on state of the arts reviewed within this project. Furthermore, those models have been deeply defined during this master thesis. By doing this, this work has studied the different possibilities on how Europe regulation may evolve for solving the TSO-DSO coordination issue. Comparing the results of the different case studies, it is possible to see that there is not one model that fits better for all the countries. Transition costs are different depending on the current situations of the countries nowadays. Furthermore, the long run efficiency is different depending on the DER penetration of each country and the market power/competition of the DSOs.