EPRI’s take on the metering revolution and the "new norm”
By: SGN Staff
Between 2004 and 2009, the production of traditional electromechanical electricity meters in the U.S. was gradually shut down in the wake of the successful introduction of solid state electronic meters. This transition was the most significant change in metering technology in over 100 years. Although it has been four years since the last electromechanical meters rolled off the assembly line, solid-state meters are still new from the utility perspective, and the industry is still becoming accustomed to their capabilities and limitations.
Solid state meters are easier to manufacture, but have a shorter field service life than their electromechanical forebears. Generally, utilities plan for a service life of 12-20 years for these new meters, significantly shorter than the life of typical electromechanical meters of up to 50 years. This will result in a significantly higher rate of nationwide meter replacement going forward. It is estimated that there are roughly 150 million electric meters in service within the U.S. today. If we assume that each will last 15 years, then no less than 10 million meters would need to be replaced each year on a sustained basis. This rate is much higher than historical norms, with smart meter deployments only coming close to this rate during the ARRA-assisted period in 2011 and 2012 (American Recovery and Reinvestment Act of 2009). Therefore, one must take pause before considering that a certain percentage of meters have "been converted.” We are not in the process of a one-time nationwide upgrade, but instead have been carried by technology evolution to a place where replacement is the new norm.
For an individual utility, it is not unusual for the replacement process of AMI systems to take as much as 5-10 years from initial planning to last meter installed. This is substantial relative to the service life of the meters themselves, and makes it imperative that the utility be able to monitor the health of their system. In addition to monitoring the present health, utilities also need prognostics (predicting the remaining functional service life of a part or system) that provide confidence that the system will continue to perform until its replacement.