The phrase, “Don’t bring me problems – bring me solutions,” is a typical response managers may give employees when encouraging them to think for themselves. The same sentiment holds true for many retailers and other light commercial building owners when dealing with the energy management systems controlling their facilities.
Much attention in the energy industry today is focused on Fault Detection & Diagnosis (FDD) and building analytics. This is indeed an important technological evolution — the ability for an energy management system (EMS) to automatically detect faults and provide a high-level diagnosis is a significant step forward from previous generations of systems, which provided only streams of data for users to analyze and interpret.
However, the ability of the EMS to detect and report on potential equipment failures is only part of the solution, especially for companies managing a geographically dispersed portfolio of light commercial buildings, such as retailers, branch banks, grocery stores and restaurants.
Most energy and facility departments are simply too busy to respond to all of the data a modern EMS can produce. For example, a chain store with 1,000 locations across the country, each with eight rooftop HVAC units, has a total of 8,000 units to manage. If 25% of those units are broken or in some state of disrepair (which is actually below industry norms1), then at any given time 2,000 HVAC units need to be dealt with in some fashion – either serviced immediately, serviced during the next preventative maintenance visit, or deliberately ignored. In many cases, the best course of action is actually to turn them off, since they are doing more harm than good, and a reset might potentially bring them back into operation.
This is just one example. Many others exist, such as communication failures, dealing with store employees who repeatedly override temperature controls, or detecting snow melt equipment left on in the summer! The sheer volume of items an EMS can detect when compared to the actual manpower available to act on those items means that even the simple fixes may not take place, resulting in wasted energy and reduced useful lifecycle of expensive store equipment.
But what if an EMS could not only report on problems, but actually do something about them? What if it could also solve problems for managers, automatically? This capability would fulfill the promise of the autonomous building.
New technology now available at Siemens called the Site Controls™ Action Engine builds upon the analytics of current generation platforms, allowing the EMS to not only detect problems, but to actually implement changes to resolve them. For example, when a failing HVAC unit is detected and adjacent units are providing sufficient airflow to the sales floor, the Action Engine automatically shuts off the failing unit for a pre-determined time interval. At minimum, this saves energy and reduces wear and tear since the failing unit does not continue to run without benefit, and the adjacent units are not required to overcompensate for the unconditioned air brought into the building. Moreover, in many cases giving the HVAC unit a ‘breather’, so to speak, may allow for it to be brought back on line for a period of time by allowing frosted coils to thaw or high head pressure to clear.
Siemens engineers estimate that a single 8-hour HVAC unit override OFF event saves an average of $8 in wasted energy. In our example of a retailer with 8,000 HVAC units, if the Action Engine automatically overrides 3% of the fleet 30 times per year (a conservative figure), the savings yielded in energy alone could exceed $57,000 annually, not to mention the reduced energy use and wear and tear on the functional HVAC units, leading to operational savings and lower capital expense for equipment replacements
In a similar way, such an autonomous building can remotely resolve communication failures, detect and notify management of repeated employee abuse of system overrides, or automatically shut off snow melt equipment when it is left on during the summer. As this technology continues to develop, the number of use cases and the positive impact will grow significantly. Consequently, the role of the EMS will finally shift from bringing managers problems to bringing them cost savings and operational efficiencies – automatically.