Energy security has become a central priority for the European Union, driven by geopolitical tensions, supply disruptions, and the need to reduce external energy dependencies. Ensuring a resilient and reliable energy system is therefore a key element of the EU policy agenda, aiming to guarantee energy affordability for citizens and businesses while maintaining the competitiveness of European industry. The presentation provides insights into the key factors for designing a secure European energy system that achieves the legally binding interclimate target for 2040.