Redefining European Energy Security: Assessing Top-Down and Bottom-Up Approaches to Energy Security of Supply

On January 3, 2026, an arson attack on powerlines leading from a Berlin heat and power plant cut off power to 45,000 homes and businesses. In less than a year, this is the second similar attack on Germany’s energy infrastructure. The ongoing Russian military attacks on Ukraine’s energy infrastructure leave the populace on rolling blackouts. These types of attacks exemplify the new dynamic of energy security and security of supply in Europe. This paper asks, how well do traditional measures of security of supply address military threats and network resiliency? Energy security of supply in Europe is split between the technical assessment of blackouts and supply security. Blackouts, such as the one affecting Spain and Portugal in April 2025 are severe and unexpected but are managed. For supply security, TSOs and DSOs have a history of dealing with disruptions of supply emanating from Russia, largely starting in 2006. Resiliency is the ability to prepare, avoid or quickly recover from network disruptions. Since Russia's 2022 invasion of Ukraine, Europe has robustly diversified and fortified the single energy market against Russian supply disruptions. This has occurred against the backdrop of Ukraine's energy system being attacked daily by Russia. In Europe, established energy security measures may underestimate or overlook further steps Russia may take to disrupt Europe's energy network. The current acts of sabotage and future kinetic threats pose a potential risk to cause short- and medium-term disruptions to industry and households. This paper 'scopes out' how energy security of supply and resiliency are defined, addressed by network operators, national and international organizations, and governments. With the backdrop of further escalation between Europe and Russia, the energy network becomes vulnerable to disruption. Central to this paper are the different scales of assessment. From households to energy communities, to cities and regions, such as the local and sub-national scale, to national governments and actors. A policy and literature review of European TSOs, national governments, and a range of policies from the European Union, including the European Commission, will be analyzed to categorize threat perceptions and responses, including responses at different scales. Greater consideration will be given to the concept of resiliency in relation to distributed generation, energy efficiency, and other localized means to mitigate supply disruptions. How well do these policy or guidelines encourage a bottom-up approach towards security of supply. The study will generate a differentiation between top-down and bottom-up resiliency. A bottom-up approach to security of supply and energy security may overlook the benefits of decentralized systems. By addressing traditional framings of security of supply, this paper revisits what security of supply means, not only for accidental blackouts, but in the face of military and covert actions. Redefining security of supply and energy security in the context of new threats and technologies requires a fuller assessment of Europe’s energy network and resiliency at a range of scales.