The ENTSOG Methodology for Cost-Benefit Analysis of Gas Infrastructure Projects (2018) provides a harmonised framework for assessing the socio-economic value of gas infrastructure investments across Europe. Developed by the European Network of Transmission System Operators for Gas, it supports the Ten-Year Network Development Plan and the evaluation of Projects of Common Interest. The methodology applies a scenario-based, incremental approach comparing outcomes with and without a project to identify net benefits. It combines monetised indicators, such as socio-economic welfare and price impacts, with qualitative assessments covering security of supply, market integration, competition, and sustainability. A standard social discount rate and long-term time horizon ensure comparability across projects. The framework also allows grouping of interdependent infrastructure components. Overall, it promotes transparency, consistency, and robust decision-making in cross-border gas infrastructure planning and investment appraisal.
