Resilient off-grid power generation using wind, solar, and gas pressure recovery in natural gas pressure regulation stations

Reliable and affordable electricity supply remains a significant challenge for gas pressure-regulating stations in remote areas with limited access to the main power grid. This study proposes a hybrid energy system that combines photovoltaic panels, a vertical-axis wind turbine, and a gas pressure recovery turbine to provide autonomous power while utilizing available renewable resources and otherwise wasted gas-pressure energy. A gas-pressure-recovery turbine was designed and analyzed using computational fluid dynamics, followed by sensitivity analysis and geometric optimization of the blade and nozzle configurations. A two-stage optimization framework integrating ensemble machine learning models (XGBoost, Random Forest, and Gradient Boosting) with a differential evolution algorithm was employed to maximize turbine torque. The optimized turbine was then incorporated into the hybrid system, and its technical and economic performance was evaluated under the climatic conditions of Baghdad, Beijing, and Chengdu. The optimized turbine achieved a 200.8 % increase in torque compared with the reference design. The hybrid system maintained a 100 % resilience index with no unmet load hours across all investigated locations. Annual electricity generation ranged from 4,109 to 5,476 kWh, while the levelized cost of electricity ranged from 0.104 to 0.182 $/kWh. The system exhibited payback periods of 3.51–4.50 years and annual CO 2 emission reductions of approximately 2.81 t. The results demonstrate that integrating renewable energy sources with gas pressure recovery technology offers a reliable and economically attractive solution for powering gas pressure-regulating stations in isolated regions.