An energy management system (EMS) is usually a system of computer-aided tools used by operators of electric
utility grids to monitor, control, and optimize the performance of the
generation and/or
transmission system. The monitor and control functions are known as
SCADA; the optimization packages are often referred to as "advanced applications".
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A control system capable of monitoring environmental and system loads and adjusting HVAC operations accordingly in order to conserve energy while maintaining comfort.