Power-to-X: A promising Roadmap for energy diversification and Greener future

The Power-to-X (PtX) system presents an innovative approach to energy conversion and storage, designed to integrate the production and utilization of hydrogen, ammonia, and methanol, thereby supporting an efficient and sustainable energy cycle. This review offers a comprehensive analysis of Power-to-Hydrogen (PtH), Power-to-Ammonia (PtA), and Power-to-Methanol (PtM) technologies, highlighting hydrogen production efficiencies of up to 80% and energy densities ranging from 33 kWh/kg (hydrogen) to 4.6 kWh/L (methanol). It is anticipated that the PtX system can facilitate a reduction in carbon dioxide emissions by as much as 80%. Furthermore, green ammonia and methanol can achieve a fully carbon-free energy cycle. In contrast to previous reviews, this work uniquely emphasises the integration of PtH, PtA, and PtM pathways, thereby addressing the gap in understanding their synergistic effects on decarbonisation. It also explores the transformative impact of these technologies on contemporary energy demands, providing a practical solution for balancing intermittent renewable energy generation with fluctuating demand, and thoroughly demonstrating the significant potential of the PtX system in tackling modern energy challenges.