SUSTAINABLE SUPPLY CHAIN NETWORK DESIGN FOR RENEWABLE ENERGY

This study designs sustainable supply chain networks for renewable energy systems, focusing on carbon dioxide (CO₂), hydrogen, and biomass. By integrating economic, environmental, and social factors, the research develops optimized networks to maximize efficiency and minimize costs.

For CO₂, the study examines the techno-economic performance of CO₂-to-fuel pathways, specifically the CO₂-CO-FTS-fuel and CO₂-methanol-fuel processes, within the U.S. A life cycle assessment quantifies environmental impacts. Results show that the FTS pathway is preferred at all selected refineries when hydrogen costs $1,000/t and electricity conversion costs are reduced by 95%, generating $8 billion annually while reducing emissions by 88.8 million tons. Sensitivity analysis highlights electricity and hydrogen prices as cost drivers. The CO₂ recycle rate and higher conversion efficiency improve the cost-effectiveness of methanol pathways.

For hydrogen, the study evaluates three delivery pathways—gaseous hydrogen, liquid hydrogen, and ammonia—as carriers, based on costs and greenhouse gas emissions. Hydrogen demand is projected for 1,927 fueling station locations under various fuel cell electric truck (FCET) market penetration scenarios. To enhance computational efficiency, binary variables are replaced with integers. Results reveal the liquid hydrogen pathway as the most cost-effective, with a levelized cost of $4.6/kg at 10% FCET penetration. Improvements in gaseous hydrogen station costs, ammonia pathway energy losses, and station scalability are recommended to enhance feasibility.

For biomass, the study investigates the techno-economic feasibility of biomass-to-biofuel with carbon capture and storage (BECCS), using corn stover, switchgrass, and miscanthus in the southeastern U.S. A two-stage mixed-integer programming model optimizes supply chains using spatial and seasonal biomass data. Results demonstrate that biofuel production is viable across market maturity levels, producing 3.01 million tons annually under high maturity. Switchgrass emerges as the dominant feedstock. Sensitivity analysis identifies operating costs and biofuel prices as profitability drivers, with a minimum selling price of $2.62/gallon. Multi-feedstock biorefineries yield higher profitability and stable production. Policy recommendations emphasize public awareness and robust biomass supply chains for long-term BECCS viability.

This research provides actionable insights for developing efficient, sustainable renewable energy supply chains.