Design and Optimization of the Turkish Green Supergrid: Multi-Commodity Network Planning from Altai to the Danube

This study investigates the techno-economic feasibility of the Turkish Green Supergrid, which extends from the Altai Mountains to the Danube and encompasses the members of the Organization of Turkic States (OTS). The main objective of the study is to demonstrate, using a multi-vector optimization model, how Central Asia's high renewable energy potential and existing natural gas infrastructure can be integrated with Europe's decarbonization goals (Green Deal). In the study, a 6-node energy network stretching from Nur-Sultan to Edirne was modeled using the Mixed-Integer Linear Programming (MILP) method. The model was run under three different scenarios—Fully Green (S0), Transition Process (S1), and Business As Usual (S2)—to minimize annual costs. The simulations simultaneously optimize electricity (HVDC), hydrogen, and natural gas flows. Simulation results revealed that the annualized capital expenditures (CAPEX) for the backbone infrastructure remained consistent across scenarios, stabilizing at approximately 0.68 billion €/year . It was determined that 8503 MW of electrolyzer capacity needed to be installed at the Edirne (Thrace) node to meet European export demand. The conversion (repurposing) of existing natural gas pipelines (TANAP, etc.) to carry hydrogen and the strengthening of the Trans-Caspian crossing have been identified as the most critical components of the project. The Turkish Green Supergrid is not just an energy transmission project, but a strategic necessity for regional energy security and green transformation. The findings prove that this infrastructure is a No-Regret investment and creates a resilient energy corridor for Europe and OTS countries against geopolitical uncertainties.