Integrating power monitoring systems
Q: Describe a mission critical facility in which you specified a system to monitor complex standby, back-up, or emergency power.
Shapiro: The financial client I referred to previously was designed to have 32 MVA, 2N medium-voltage utility services, an N+2 standby-generator plant, more than 16 MVA of UPS power, and 100,000 sq ft of computer room. All of these systems require the EPMS to interface with power quality monitoring at the utility, generator plants, UPS systems, and at the computer room distribution. Synchronized millisecond time stamping is required for all the major distribution systems with live electrical one-line diagrams and live load information down to the branch circuit breaker serving the computer equipment in the rack on the computer floor. The system has a dedicated LAN infrastructure with redundant servers and looped communication systems to eliminate the risk associated with a loss of communication in a single communications path. All monitoring systems have dedicated power redundancy to isolate the system from the impact of an electrical distribution failure and ensure continuous monitoring. A dedicated monitoring station is located in the operating engineers’ office with summary system alarms cross connected to the BMS. The system can be accessed through connection at any internal facility network connection. The system is not accessible outside of the facility via modem or Internet connection to ensure system reliability and security.
Strang: Unfortunately, we have not had the opportunity to specify a dedicated power monitoring system for such a mission critical facility. The power monitoring capability was built into the UPS equipment, which was out of our scope of work.
Young: One of our projects was a rather large data center and office building complex with on-site power generation installed to back up the data center, and as an additional benefit, provide power to the complex. With the power monitoring system installed, the owner is able, based on the power consumption recorded prior to an outage, to continue to provide power to the office complex in addition to the data center.
Q: Looking 2 to 5 years into the future, how do you think power monitoring systems will change?
Shapiro: I believe the HMI will become easier to use and better interfaces will be developed for use with portable and mobile devices. Power quality resolution and event capture will be enhanced, more devices will have communications, and power quality metering ability will be standard. These improvements will reduce the cost of the EPMS overall, make the EPMS easier to install, and even enable them to be cost effective to retrofit into a facility.
Strang: Looking two to five years into the future, I can see power monitoring systems having roughly the same features as now, except more cost effective due to competition and proliferation. We may see them more integrated with other systems (i.e., EMS/BMS) as a standard. I think with energy conservation and verification, and the general green movement, power monitoring systems will become a standard in system design, rather than an amenity only afforded by higher end facilities. Capturing the power flow of renewable source integration in distributed generation applications will also drive the need for power monitoring systems.
Yoon: We've traditionally focused on customer-financed and installed power monitoring solutions. If it was low cost/no cost, it would end up on every project, but it isn't. However, with utility-company smart-meter initiatives starting to materialize, many of our clients view that as an opportunity to defer/avoid the direct capital investment associated with power monitoring and participate in demand response program energy markets. It should be a win-win: the utility companies should be able to have more reliable power grids and building owners should be able to reduce operating costs.
The primary challenge is more of a legal than a technical issue. Who owns the smart meter energy usage information that is collected, how it can be used, and should it be made public? For example, in major municipalities, we're starting to see the adoption of benchmarking ordinances with mandatory reporting of building energy usage through Energy Star. While there are not yet formal penalties, such as cash fines to penalize poor scores, these mandatory public disclosure requirements still concern many building owners. The standard metric of energy use intensity doesn't necessarily reflect efficiency of the individual building systems, but rather overall energy usage for a given square footage of building area. Whether right or wrong, many new Class A buildings have been given a proverbial black eye through lower than expected Energy Star scores compared to what we would normally consider antiquated and obsolete buildings. This would seem to put agendas of energy efficiency and economic development at odds. Some have suggested that this gap can be bridged by linking a building's energy usage to economic contributions of the businesses within that building. It should be interesting seeing how our engineered solutions evolve to fit into this new world.
Young: More Internet protocol-based systems will be installed to minimize initial installation costs and to not only allow integration into BMSs, but also allow occupants to see a dashboard of energy consumption for their building.