[en] This report provides an independent and forward-looking assessment of the EU's gas supply security by assessing the relevance of the 32 new gas infrastructure projects on the EU's 4. Projects of Common Interest (PCI) list which are eligible for European public funds. It also analyses an additional 5 new natural gas infrastructure projects in the EU that are not part of the PCI list The 32 natural gas infrastructure PCI projects combined are calculated to come at a cost of 29 billion Eur and would add 338 GW capacity to the EU natural gas infrastructure system, which is already approaching 2000 GW of pipeline and LNG terminal capacity. The European Commission's projections currently estimate that achieving the 2030 climate and energy targets will result in a reduction of natural gas by 29% - from 415 bcm in 2015 to 297 bcm in 2030. The report looks at the implications of that scenario on the need for new infrastructure from a gas security of supply point of view, but also considers a wider range of future natural gas demand scenarios and extreme supply disruptions cases. The report concludes that the existing EU gas infrastructure is sufficiently capable of meeting a variety of future gas demand scenarios in the EU28, even in the event of extreme supply disruption cases. This suggests that most of the 32 gas infrastructure projects on the 4. PCI list are unnecessary from a security of supply point of view, and represent a potential over-investment of tens of billions of Eur, supported by European public funds. Key findings: - 1: Under normal market conditions, existing gas infrastructure in 2030 suffices to meet gas demand in both an 'On Track' and 'High Demand' scenario. - 2: Existing gas infrastructure in 2030 is resilient to a wide range of potential extreme supply disruptions, including year-long disruptions from Ukraine, Belarus and Algeria. The loss of supply from Russia or Algeria is compensated by imports from other sources, primarily via existing LNG terminals in the west of Europe. - 3: Investments in projects included in the 4. PCI list are found to be unnecessary to safeguard security of supply in the EU28 and therefore risk to become stranded assets supported by European Union public funds. This remains true in scenarios with higher natural gas demand in 2030. Minor investments in some of the projects included in the 4. PCI list are found to be relevant to solve security of supply issues outside the EU28, in Bosnia-Herzegovina (the model does not select investments in any of the 5 additional projects we have considered on top of the 4. PCI list). However, most of the projects are shown to be superfluous from an economic point of view. Furthermore, from a methodological point of view, the report confirms previous findings that using an integrated gas-electricity approach to infrastructure planning is essential to avoid over-investments