Beyond 'Wow': Real Gains From An EMS Upgrade
By James Piper, P.E. July 2011 - Power & Communication
When properly used, energy management systems (EMS) can reduce facility energy use, improve customer comfort, increase building system reliability and help keep maintenance costs in check. But an EMS does not last forever. Eventually, it will require upgrading or replacement. The problem for facility managers is recognizing when it is time and exactly what benefits they would achieve by upgrading or replacing their existing system.
It's easy to be wowed by new systems. But it is important to remember that not all facilities need or will benefit from all of the features and functions provided by these systems. If the existing system cannot meet the current level of need, then opportunities to save energy and improve performance will be missed. But if the replacement system offers capabilities that will never be used, facility managers will be unnecessarily committing resources that could be better used to upgrade other elements in the facility.
Evaluating EMS Requirements
One of the most important factors to remember when evaluating EMS requirements is that facilities and their operations are always in a state of flux. As a result, facilities managers must constantly be adjusting their techniques and procedures to match those changed requirements.
Start by identifying what the system is expected to do. What type of control strategies, such as equipment start/stop and load shedding, are needed to perform the necessary tasks? What type of data, such as customer energy use necessary for internal billing, must the system provide? How important is customer comfort?
Once the system needs have been identified, it is critical that managers conduct an examination of the existing system to determine how well the existing system is functioning and whether it has the capabilities that are needed.
When evaluating the existing system, be honest. Too often the EMS is blamed for problems that are due to lack of maintenance or improper setup at the equipment level. For example, the bypassing of controls in order to keep equipment operating is not something that can be corrected by any EMS.
Another factor to consider is how well the EMS itself has been maintained. System manufacturers routinely offer upgrades to EMS hardware, software and firmware. If problems are being experienced in the operation of EMS and those upgrades have not been installed, that may be the place to start.
Compare the list of functions that the system is expected to perform with the functions that it is capable of performing. Identify those strategies that are lacking. For example, time of day metering for electricity use has traditionally been limited to larger facilities. However, changes in utility metering techniques as well as implementation of portions of the smart grid are resulting in the expansion of those who must pay different rates for electricity use based on when it is used. If facilities are to provide the greatest level of control over their energy costs, their EMS must be capable of factoring time of day rates into its control strategies.
Take a close look at the vendor who is currently servicing the EMS. Vendor performance issues frequently mask themselves as system issues. What may be needed is a change in the level of support by the system vendor rather than a system upgrade or replacement.
One of the best sources for information when evaluating an existing EMS is the system operator. System operators can provide feedback on what is really going on with the system, not just what the system is thought to be doing, and also what would be needed for improvement. They are also the best ones to understand the level of training required for the existing and possible future systems.
There are a number of factors that influence whether an EMS needs to be upgraded or replaced. For example, if the existing system is operating at its maximum capability and the need exists to expand the number of components connected to the system or to add additional control functions, upgrading or replacement are the only options.
Obsolescence is another important factor to consider. System manufacturers support the operation of their equipment for only a set period of time, typically 10 or 15 years. After that, it becomes increasingly difficult to obtain software upgrades, replacement components and even technical support. Additionally, changes in technology are coming so rapidly that older systems will be significantly slower in operation.
Another major factor influencing the upgrade/replace decision-making is a change in needs on the part of the facility. Older generation systems may not include all of the functions required to implement the energy and facility management strategies currently needed.
Today's systems are almost entirely network-based, allowing managers to connect devices in separate facilities to a single system using a wide range of IT networks. By piggybacking on an existing network infrastructure, managers can reduce installation, operating and maintenance costs. These networks also offer the additional advantages of speed, reliability and flexibility. Additionally, a network-based EMS offers the potential of allowing users to access the system from both inside and outside of the facility. Authorized personnel can easily access the system remotely during off hours to diagnose and correct equipment problems. Even vendors can remotely access and troubleshoot the EMS and connected equipment.