INTRODUCTION

Developments in energy markets are reflected, sometimes only after a while, in the cases that are submitted to the European Union courts in Luxembourg. Provisions of the Treaty on the Functioning of the European Union (TFEU), such as the rules governing State aid or environmental protection, may have to be interpreted in light of new policy objectives. Furthermore, the validity of new EU legislative measures (regulations or directives) may be challenged, e.g. on the ground that a proper legal basis in the TFEU is lacking. This is one of the reasons why many disputes brought before the European Union courts have an institutional dimension, raising questions about the division of competences between the European Union and its Member States, about the balance of power between EU institutions (Parliament, Council, and Commission), or, more specifically, about the dividing line between the powers of the legislator and those of the energy regulator or between the powers of the European regulator and those of the national regulator in each Member State.

This chapter is organised as follows. It begins with the topic of energy solidarity (§2), followed by a discussion of several rulings relating to the internal market (§3). Subsequently, in §4, I will focus on appeals against decisions by the Agency for the Cooperation of Energy Regulators (ACER). Next, it addresses a few cases concerning EU competition law (§5) and the EU rules concerning State aid (§6). In §7, the focus will be on investment arbitration under the Energy Charter Treaty (ECT).