At least one model is associated with one or more manipulated variables and one or more controlled variables, which are associated with a cascade liquefied natural gas facility. Adjustments to the one or more manipulated variables are made using the at least one model to maintain the one or more controlled variables within defined limits. For example, a controlled variable may identify an overall load placed on multiple refrigeration systems in the facility. The one or more manipulated variables may be adjusted to increase the overall load placed on the refrigeration systems. The overall load can be determined by identifying a maximum of: a projected feed gas rate to operate a propane refrigeration system at maximum load, a projected feed gas rate to operate an ethylene or ethane refrigeration system at maximum load, and a projected feed gas rate to operate a methane refrigeration system at maximum load.