This book contributes to a new paradigm shift towards sustaining the Energy Charter Treaty, which remains the key instrument on global energy governance and foreign investment. The book detangles the misunderstandings produced by Achmea and Micula, drawing upon the consequences of international energy investments in the EU. The author demonstrates a clear solution where ECT tribunals respect the autonomy of EU law, while resolving intra-EU energy disputes. She achieves this by presenting for the first time comprehensive scholarly, jurisprudential and empirical findings proving that EU Law operates a functional role in analysing breaches of investment treaty protection. If applied effectively, this new approach can produce valid and enforceable intra-EU arbitration awards. At a time when the ECT is being modernised, the conceptual standpoints presented offer a problem-solving approach to assist the arbitrator, academic, policymaker and legal practitioner in understanding both the present and the future of EU energy investments. The book focuses on the low-carbon power sector, including electricity, nuclear and renewable energy disputes. The arguments advanced can be transplanted to other economic sectors and regional investment blocks, including CETA, EU-Singapore, EU-Mercosur, EU-Mexico and the EU-Australia Trade Agreements.