Identify and assess multiple decarbonization pathways such as full electrification, hybrid systems, networked geothermal adoption, efficient gas technologies, alternative fuels, and slower transition approaches based on Illinois-specific conditions. Quantify and compare each pathway’s technical feasibility, economic costs, environmental benefits, and equity impacts relative to a BAU scenario. Support informed decision-making by providing the ICC and stakeholders with objective, data-driven evaluations of trade-offs, risks, and benefits across pathways. Guide long-term energy planning to ensure safe, reliable, equitable, and cost-effective decarbonization of Illinois’ natural gas sector, consistent with state climate goals and legal mandates. The findings from this study will inform ICC policy development, utility planning, and stakeholder engagement processes, ensuring that Illinois’ energy transition is both environmentally sustainable and economically equitable.