This article reviews the issues facing co-electrolysis and its applications to the power-to-methanol process. Co-electrolysis is an attractive process for syngas production that uses excess generated electricity. In extended applications, syngas produced from co-electrolysis can be used for various applications like methanol production. In this review, the power-to-methanol process is comprehensively discussed from a process systems engineering viewpoint. The subjects discussed include the reason to choose methanol as a final product, the latest progress in power-to-methanol projects, and a comparison of methanol production from H2-CO (from co-electrolysis) and H2-CO2 mixtures (from electrolysis). Syngas production pathways from co-electrolysis and electrolysis are further investigated, and potential power-to-methanol schemes using co-electrolysis are deployed. Lastly, research directions are proposed to accelerate power-to-methanol commercialization. © 2018 Elsevier Ltd