MeOH Synthesis with Flexible Electrification. Methanol is one of the most widely used chemicals in society, with a production capacity of nearly 10 million tons per year in the US . The methanol synthesis process involves the reaction of carbon monoxide (CO) or carbon dioxide (CO2) with hydrogen (H2) to generate methanol (MeOH). As with many other chemical processes, synthesis gas required for methanol synthesis is typically generated through SMR. Here, we consider sourcing synthesis gas via the addition of an electrification system that consists of an electrolysis unit and a reverse water shift gas (rWGS) unit. The generated syngas by the electrification system substitutes 50% the syngas produced by the steam reformer. This strategy lowers the consumption of natural gas and the operational cost of the steam reformer. In Figure , solid lines are streams that have constant material flows. The dash lines represent streams where material flows change over time. To harness the flexibility of the electricity market, the operating mode of the electrolyzer needs also to be flexible. Specifically, the amount of hydrogen produced at each time interval depends on the electricity price. During off-peak hours, when the electricity price is low, more hydrogen can be produced than is needed and the excess hydrogen is stored in the hydrogen tank. The electrolyzer operates under partial-load during the electricity peak hours or even completely shuts down. The stored hydrogen is released during these periods to meet the constant hydrogen demand of rWGS. With a continuous supply of hydrogen and CO2, the rWGS unit generates a constant flow of syngas fed to the methanol reactor. By tuning the H2/CO2 ratio and the reaction condition of rWGS, the generated syngas has the same composition as the syngas produced by steam reforming. We reduce the load of steam reforming by half and supplement the required syngas via electrification. process sources hydrogen from SMR. We retrofit the process by adding a flexible electrolysis unit and a reverse water gas shift (rWGS) unit. The syngas produced from electrolysis and rWGS units partially replace the syngas produced by steam reforming. We harness electricity market dynamics by optimizing the electrolyzer operating mode every 15 minutes within a one-year planning horizon. A hydrogen storage facility provides the system with flexibility by supplementing hydrogen when the electrolyzer is down; this absorbs excess hydrogen produced by the electrolyzer during the low energy price periods.