<![CDATA[Climate change and Indonesia’s net-zero emission target have accelerated interest in hydrogen as a low-carbon energy carrier, while the high cost of dedicated hydrogen infrastructure has encouraged the repurposing of existing natural gas pipelines. This study evaluated the technical and economic feasibility of repurposing the West Java FSRU–Muara Karang ORF subsea pipeline for hydrogen blending transportation. The research applied an integrated techno-economic assessment combining hydraulic simulation, material integrity evaluation, infrastructure requirement analysis, and financial feasibility assessment. Simulations were conducted for hydrogen blending concentrations of 0–30% under minimum, normal, and maximum plant-load conditions, with results validated through Python and MATLAB cross-checking. The results showed that increasing hydrogen concentration increased flow velocity by up to 33.5% and pressure drop by up to 27.0%, while the maximum pressure drop remained below the pipeline operating limit. API 5L X52/X65 pipeline materials were technically suitable; however, hydrogen embrittlement considerations supported an initial blending limit of 15%. From an economic perspective, both injection scenarios were feasible, but ORF-side injection demonstrated better performance, achieving a net present value (NPV) of USD 32.7 million, an internal rate of return (IRR) of 15.5%, a payback period of 6.1 years, and a levelized cost of hydrogen transportation (LCOHT) of USD 0.33/kg H?. Therefore, ORF-side injection with hydrogen concentrations of up to 15% is recommended for initial implementation, accompanied by periodic inspection, monitoring, and further experimental validation.]]>
