Simulation and Validation of Green Hydrogen for the Production of Renewable Diesel: Case Study in La Guajira, Colombia

This study validates green hydrogen (H${}_2$) production from a 15 kWe wind–solar PV microplant under real operating conditions and quantifies the renewable diesel (RD) potential from oil hydroprocessing (with palm oil as the base case) via detailed stoichiometric balances. The electric output feeding two electrolyzers was monitored for six months (December 2024–May 2025). Three H${}_2$ production models were calibrated against the experimental results; the model with the best fit achieved R${}^2$ = 0.9848 and MSE = 130.05. Using the estimated H${}_2$ production, monthly balances were established for palm oil TAGs (POP, POO, POL, PLP, and SOS) across various deoxygenation routes—namely decarboxylation (DCX), decarbonylation (DCN), and hydrodeoxygenation (HDO)—with coproduct closure (propane, CO${}_2$/CO/H${}_2$O). The hybrid plant operated above the electrolyzers’ 2.88 kWe minimum, raising the effective H${}_2$ output (which peaked in February–March) and, thereby, the RD potential. The specific H${}_2$ demand followed the gradient of HDO > DCN > DCX; for POP, the global demand was 0.30 kg (saturation) + 1.20 kg (cracking) + 2.10 kg (DCN) or 2.55 kg (HDO), highlighting the carbon–hydrogen trade-off. The results indicate that green-H${}_2$–HDO integration is technically feasible and scalable in La Guajira; the choice of route (DCX/DCN vs. HDO) should align with local renewable availability to either maximize the liters of RD per kg H${}_2$ or conserve carbon.