This piece was originally published in the April 2017 issue of electroindustry.
Ryan Fetgatter, Partner, EZ Meter
Although electric submetering has been around for years, most people are unaware of its importance to energy consumption management. This mindset is poised to change, however, as the future demands accountability. The most accurate, efficient, practical, and affordable solution to monitoring electric energy consumption for management, preventive maintenance, and billing purposes is electric submeters.
When government programs began to promote energy conservation, they used a platform based on an algorithm: volts × amps × power factor = watts. Though brilliant on paper, the model is flawed. It cannot be relied on for analysis or benchmarking purposes. This prompted the formation of the NEMA Electrical Submetering Section (5ESM) to educate the public and unite the industry in one cohesive voice.
Submeters are the electrical metering devices and associated data acquisition and communication equipment that are connected downstream from the utility meter and provide details of energy use for one or more electrical loads. Such equipment is rated at not more than 600 V AC.
Currently, submeters are lumped into a larger safety standard developed for utility meters that don’t operate or function in the same manner as an electric submeter. To this end, 5ESM is working with UL on a standard that addresses safety for electric submeters. A related task is to establish an accuracy standard. Determining the testing ranges has been complicated, but the subcommittee expects to have a version ready to present to ANSI within the next six months.
The section also promotes the benefits of electric submetering within key market segments: the revenue-grade electric kilowatt-hour submeter and the electric energy management and monitoring submeter.
Revenue-grade billing submeters measure the consumed kilowatt-hour of a load with the intent of billing for electricity used. Common applications are multi-family housing, marinas, RV parks, retail rentals, and other properties where a manager wants to pass electrical consumption onto tenants.
Electric management and monitoring submeters accurately monitor real electrical consumption, productivity, and quality for benchmarking, regulation, and preventive maintenance. Data may include kilowatt-hours, volts, amperes, power factor, kVAR, and kVA—all beneficial to facility and plant managers.
By monitoring an HVAC unit, for example, a facility manager can see the factors that fall out of a desirable range over a period of time. The manager who can forecast that a component is going to fail can properly prepare for it. Whether the equipment is serviced or replaced, the end result is no surprise shutdowns.
The 5ESM Government Relations Committee is presenting a common platform to federal, state, and municipal entities who are writing submeter language. According to Navigant Research, legislation is being written now that will turn a $949.7 million-per-year industry into a $2.5 billion-per-year industry by 2024.
When that date arrives, will you have used submeters to adapt to the changing times?