ENNOH develops and maintains the cost–benefit analysis methodology for hydrogen infrastructure and applies it to evaluate the impacts of projects submitted through the TYNDP. Using scenario-based modelling, the CBA examines how each project influences system costs, decarbonisation progress, security of supply and overall system efficiency. The results are presented in a transparent and harmonised manner to support policymakers, regulators and stakeholders in understanding the value of proposed infrastructure developments. ENNOH does not decide which projects receive PCI or PMI status, does not make funding recommendations and does not approve or reject projects. Its mandate is limited to providing a consistent, analytical assessment of project impacts.