Demand Control has historically been performed by a Load Controller System or Demand Control System which is an automatic device that monitors whole-house grid consumption and turns off major loads as the peak demand approaches the demand limit setting.
Energy Management Systems are a newer type of Demand Control System (or Load Controllers) that monitor the energy of the individual large loads and solar generation along with the whole-house grid consumption. It is the load control part of the system that separates it from simple energy monitoring systems.
Whereas Demand Control is primarily focused on managing multiple loads to maintain the demand below a pre-set limit during on-peak periods, Energy Orchestration (EO) or load orchestration is more general. EO refers to the automated control of any loads to achieve a wide range of outcomes. Desirable outcomes might include maintaining the total demand below a pre-set limit (as in most demand control scenarios); minimizing the cost of charging batteries or electric vehicles by taking advantage of cheap energy periods; supporting net zero initiatives by distributing solar and stored energy appropriately throughout the day. The possibilities are endless. What they all have in common is using load coordination to achieve specified energy.