management systems save about 10 percent of
overall annual building energy consumption.
An energy management system (EMS) is a computer that controls the
operation of all major building systems, in order to run the
building efficiently and effectively. An EMS can reduce a
building's overall energy use by about 10 percent.
Today, nearly one-third of all U.S. buildings larger than
100,000-square feet have an EMS. Unfortunately, many of these
systems are not saving as much energy as they could be saving. In
one study, 5 out of 11 energy management systems were found to be
This Design Brief outlines several steps that building owners and
designers can take to ensure that an EMS produces maximum
- Take advantage of advanced control strategies that make good
use of EMS computer power.
- Specify the EMS clearly and accurately. (For instance, provide
complete information about intended performance, control
strategies, and project team responsibilities.)
- Utilize the commissioning process. This process requires
frequent reviews of all building systems (including the EMS)
throughout design and construction, as well as performance tests