Environmental and Economic Trade-Offs of Power-to-X Strategies: A District-Scale Renewable Energy Community Case Study

Sector coupling strategies are increasingly adopted to improve the flexibility and efficiency of renewable energy systems by integrating multiple end-users, energy sectors, and conversion technologies. However, their widespread deployment relies on additional infrastructure and energy conversion processes, raising questions about the associated environmental and economic trade-offs. Despite the growing interest in Power-to-X technologies, integrated assessments simultaneously evaluating energy, economic, and environmental performance at the district scale remain limited. This study proposes an integrated framework combining techno-economic analysis and life cycle assessment to evaluate alternative Power-to-X strategies within a regenerated renewable energy community in Southern Italy. Three sector coupling pathways are compared: Power-to-Power, Power-to-Gas, and Power-to-Gas-to-Power. The results highlight different trade-offs among the investigated configurations. The Power-to-Power scenario achieves complete renewable electricity self-consumption and increases system self-sufficiency from 46% to 71%, whereas the Power-to-Gas configuration provides the shortest payback period (6 years). From an environmental perspective, the baseline, Power-to-Power, and Power-to-Gas scenarios reduce average life cycle impacts by 53%, 44%, and 40%, respectively, compared with the business-as-usual configuration, while the Power-to-Gas-to-Power scenario exhibits slightly higher impacts due to the additional fuel cell system. Furthermore, the environmental ranking of the scenarios depends on the adopted system expansion assumptions, particularly the avoided burden approach. The proposed framework provides a comprehensive basis for evaluating sector coupling strategies in renewable energy communities, supporting decision making through the integrated assessment of environmental performance, economic viability, and energy self-sufficiency.