A controller for a HVAC and/or refrigeration system, the controller comprising: one or more interfaces operable to communicate with components of the HVAC and/or refrigeration system, the components comprising a power factor correction (PFC) subsystem and one or more motor drives; memory operable to store instructions; and processing circuitry operable to execute the instructions, whereby the controller is operable to dynamically adjust an output voltage setpoint for the PFC subsystem, the output voltage setpoint determined based at least in part on estimating a load associated with one or more components of the HVAC and/or refrigeration system that receive voltage via the PFC subsystem; characterized in that : to determine the output voltage setpoint based at least in part on estimating the load, the controller is further operable to: determine a target efficiency value for the HVAC and/or refrigeration system based on the load; determine the output voltage setpoint based on the target efficiency value; and wherein to determine the target efficiency value for the HVAC and/or refrigeration system, the controller is further operable to: determine individual efficiency values for each of the PFC subsystem and the one or more motor drives based on the load; and calculate the target efficiency value for the HVAC and/or refrigeration system based on the individual efficiency values. one or more interfaces operable to communicate with components of the HVAC and/or refrigeration system, the components comprising a power factor correction (PFC) subsystem and one or more motor drives; memory operable to store instructions; and processing circuitry operable to execute the instructions, whereby the controller is operable to dynamically adjust an output voltage setpoint for the PFC subsystem, the output voltage setpoint determined based at least in part on estimating a load associated with one or more components of the HVAC and/or refrigeration system that receive voltage via the PFC subsystem; characterized in that : to determine the output voltage setpoint based at least in part on estimating the load, the controller is further operable to: determine a target efficiency value for the HVAC and/or refrigeration system based on the load; determine the output voltage setpoint based on the target efficiency value; and wherein to determine the target efficiency value for the HVAC and/or refrigeration system, the controller is further operable to: determine individual efficiency values for each of the PFC subsystem and the one or more motor drives based on the load; and calculate the target efficiency value for the HVAC and/or refrigeration system based on the individual efficiency values. determine a target efficiency value for the HVAC and/or refrigeration system based on the load; determine the output voltage setpoint based on the target efficiency value; and wherein to determine the target efficiency value for the HVAC and/or refrigeration system, the controller is further operable to: determine individual efficiency values for each of the PFC subsystem and the one or more motor drives based on the load; and calculate the target efficiency value for the HVAC and/or refrigeration system based on the individual efficiency values. determine individual efficiency values for each of the PFC subsystem and the one or more motor drives based on the load; and calculate the target efficiency value for the HVAC and/or refrigeration system based on the individual efficiency values. <EOS>