From concept to deployment: A review of carbon-to-methanol pathways for e-methanol

This review investigates the Carbon-to-Methanol (CTM) pathway for e-methanol production, in which captured CO 2 is directly hydrogenated with renewable hydrogen. CTM is gaining attention as a scalable route for converting renewable energy into liquid fuels, yet its system design remains loosely defined. The absence of a clear design framework has led to diverse implementations, each shaped by local energy conditions, carbon sources, and integration strategies. This diversity makes it difficult to evaluate performance or guide replication. To address this, the review systematically analyzes the key design dimensions of CTM systems, including power supply, electrolyzer selection, CO 2 sourcing, reactor configuration, and integration strategy. By mapping these components and their associated challenges, the review provides a structured overview of how CTM systems are currently implemented and highlights the diversity of approaches that shape their technical and operational characteristics. • CTM emerges as a scalable route for renewable methanol in Power-to-X systems. • CTM offers flexibility and diverse objectives across power, electrolyzer, CO 2 capture, and reactor design. • CTM introduces unique thermal and integration challenges driving innovation. • Industrial projects adopt modular CTM designs for cost efficiency and site adaptability. • CTM advancement requires alignment of academic and industrial strategies.