11. How Much Gas Is Enough?: Energy Security and Natural Gas Infrastructure in the Baltic Sea Region

As a pushback to Russia’s dominance in the Baltic Sea region gas market and in the effort to boost the energy security of the region, countries in the region have undertaken two interrelated initiatives: (1) diversification of gas supplies and (2) development of the market’s interconnectivity to ensure region’s integration. With an overview of natural supply in the Baltic Sea region as a backdrop, this chapter adopts a measure of supply security–Residual Supply Index (RSI)–to capture the so-called ‘credible threat’ idea, according to which sheer existence of infrastructure that diversifies supply provides energy security benefits. The RSI-based model presented in this work is simple enough to be used and understood by non-experts but flexible and customisable enough to incorporate, envision, and assess many sophisticated scenarios, depending on what the question at stake. It can provide a point of departure for new research that incorporates measures of interconnectedness and/or intra-regional co-operation, as a part of the security of supply equation.