The energy crisis, which the EU faces since Autumn 2021 and especially dramatically since March 2022, has once again brought up the issue of stable and affordable energy supply. The mechanisms of crisis management at the EU's disposal did not allow it to react to the situation effectively, although the new energy resources price spike was caused by 'old' reasons, known to the EU from its experience of 1970-1980s: the resources deficit and political instability in the supplier region. What was new was that paradoxically, the EU energy policy, instead of preventing or at least smoothing the crisis, made it worse. The authors consider the driving forces that stand behind the development of EU energy policy and, proceeding from that, explain why, with a chronic energy resources deficit, the EU was steadily abandoning its long-term contracts with suppliers and calling on its member states to proceed with a nuclear phase-out. Why, under the conditions of post-pandemic energy growth of demand on the world market and an unprecedented price spike, it took these seemingly illogical steps: it refused to start the newly built gas pipeline Nord Stream-2 and was keen to buy costly LNG from alternative suppliers and to continue the development of unreliable and expensive renewable energy while gas prices on the spot markets kept breaking the records. To define the driving forces of the EU's energy policy both international relations (realism, liberalism, social constructivism and neo-Marxism) and European integration theories (intergovernmental approach, institutionalism, neofunctionalism and communication theory) are applied to cover each aspect. Rational approaches such as realism and liberalism, as well as neofunctionalism and some other theories do not yield any insights into the driving forces and practical steps taken by the EU during the 2021-2022 energy crisis. Theories, which have social approach at their basis - social constructivism, neo-Marxism, etc., offer a more logical explanation of the EU's decisions.