Modeling and simulation of Power-to-X systems: A review

•A review of recent system-level simulations of P-t-X.•P-t-X system configurations with their performance, environmental impact, and cost.•Various advantages and disadvantages of P-t-X system pathways.•P-t-methane is the most preferable P-t-X pathway. Power to X (P-t-X) denotes methods for converting renewable energy into liquids or gases, which can be stored, distributed or converted to valuable products. Furthermore, P-t-X can provide grid stability in connection with fluctuating electricity from renewable sources. One of the essential steps in determining the feasibility of a P-t-X system for the market is the thermodynamic, techno-economic, and environmental assessment through mathematical modeling and simulation. In this review paper, different P-t-X system configurations with their performance, environmental impact, and cost are presented. This paper only includes literature about system-level mathematical modeling and simulation studies. In this regard, an introduction to various P-t-X processes including all the stages from the power generation to the upgrading of the final product (X) is firstly presented, followed by several key system-level P-t-X studies, which consist of thermodynamic, techno-economic, and life cycle assessment analyses, published between 2015 and 2020. Finally, conclusions drawn from the previous studies and suggestions for future studies are given.