The Electric Meter: Is Almost Right Good Enough?

By: Lynn Frank

Does it make a difference to you how accurate your electric meter is? In the emerging era of customer choice and increasingly competitive margins, the answer should not be found in the unfortunate lessons of experience.

While some electric utilities have comprehensive policies and practices to ensure accurate meter registration, few utilities do. The failure to accurately meter loads has not had financial consequence for utilities assured of revenue recovery in a franchised service area. Losses are simply allocated across the customer base in rates designed to meet revenue requirements. The same will not be true in a deregulated market. Customer choice will segment the market with different customers being served by different suppliers. There will be a rude awakening when suppliers and customers learn that they cannot account for the loads being placed on the system.

Inaccurate meter registration extends across all customer classes, but is most significant in the larger commercial and industrial accounts, the accounts of greatest interest in deregulation. The problems are even more acute in submetering. Aggregators will find the submetering of regional and national retail outlets to be more speculative than precise.

In residential and small commercial accounts, the problems of inaccurate meter registration are usually associated with the meter itself. Meters installed before the 1960 introduction of magnetic suspension had jewel and bearing suspensions. After more than 30 years of wear and dirt, these meters slow down. Old meters were not designed for the loads being drawn by contemporary lifestyles. The rapidly turning disks rise with groves carved into the disks as they are braked against the magnetic supports. Some vintages of meters have withstood the test of time better than others. Utilities have whole classes of "obsolete meters" which should be, but often have not been, taken out of service. These meters may have problems with gears in the register or suffer lapses in registration due to overheating from the sun.

Utilities without rigorous acceptance testing may have installed meters that were out of calibration when delivered decades ago. It is not uncommon to find meters in service with test certificates older than the person performing the test. While many states have comprehensive weights and measurement standards, those standards generally do not apply to the utility meter. As a result, the scale you use at the corner grocery store to weigh your bananas may be calibrated to tighter tolerances than your electric meter.

While few customers would even know their meter is inaccurate, there are an unfortunate number of customers who do. An industry built on the principle of universal service serves by definition all kinds of people, including those who would steal. Diversion is a craft practiced by some of the most ingenious if unscrupulous people. It can take the form of tampering with the meter in ways so bold as to be seen by a neighbor or so subtle as to be caught only by a practiced eye. It can take the form of tampering with the service through an alternate drop bypassing the meter. More troubling are the rare but not unknown actions by knowledgeable people who have taken it upon themselves to adjust the calibration of their metering and who may even offer the service to friends and neighbors.

In the larger commercial and industrial accounts, the calibration of the meter is only part of the problem. Inaccurate calibration can be a significant source of error, but the greater problems are often behind the meter and can only be identified in a comprehensive audit of the metering installation.

Whole branch circuits have been left outside of the meter registration. Literally tens of thousands of dollars of power have been donated to an unwitting, but presumably grateful beneficiary. Utility metering personnel range in experience and qualifications. The metering installation may not match the service, failing to register all of the load. Reactive power is often not metered at all. A current transformer may be reversed resulting in only one-third of the load being registered. The billing multiplier may not match the current transformers with either the utility or the customer making a financial donation with each rotation of the disk.

This most often happens when changes in service result in changes in current transformers. Replacing 200:5 transformers with a multiplier of 40 with 1000:5 transformers with a multiplier of 200 can result in significant underbilling, if the change is not accurately recorded. Either the meter or the current transformer cabinet may not be sealed inviting tampering. Or the billing schedule may simply not match the service. Uncommon problems? Not at all.

Utilities have the ability to reconcile charges and recover at least some of the lost revenues, if they discover the problem. The utility also has the ability in a franchised service area to balance loads and revenue requirements. What liability or recourse does a power marketer have? It is one thing to seek recoveries from a customer who has no choice in suppliers, it is an altogether different matter in a competitive environment. Customers have a hard time understanding why they should pay for your mistakes. Without a comprehensive program to audit polyphase installations on a timely basis, those mistakes can become quite costly.

Submetering is in a class all of its own. The respective governmental jurisdictions have had different policies and practices with respect to submetering and those policies and practices have changed over time. Submetering for billing may not be allowed today in a jurisdiction, but may have been allowed some time in the past and grandfathered under current regulations.

Problems in submetering are endemic. The meters may not be utility revenue metering quality. Product accuracy of plus or minus 10 percent may have once been acceptable for submetering purposes, but would not be accepted for utility billing. Installations may demonstrate more creativity than knowledge. Tenants have unknowingly been paying one another's electricity bills or for the lights in the parking lot.

A major mall owner was losing hundreds of thousands of dollars a year allocating costs from master utility meters through tenant installed submetering. The submetering installations often bore no relationship to the service being provided, perhaps reflecting stock on hand rather than correct meter application. Demand was often set at intervals unrelated to the billing schedule, if demand was even measured. Whole circuits were not metered at all. Any aggregator serving a regional or national outlet in one of those malls would have no real knowledge of the requirements bid or served. Those malls happen to be in a state which will begin customer choice within a year.

The presumption that all electric utilities maintain accurate metering systems is not well founded in practice. Even if they have adopted well intended testing policies, they may not have had the resources to implement those policies. Relying on installed submetering to aggregate loads is a speculative, if not foolish, endeavor. Simply calibrating the meter will not achieve accurate accounting of loads. A comprehensive program to ensure accurate metering installations and sealing of those installations should be an integral component of any comprehesive policy. In an era of customer choice, the value of that approach will be affirmed with experience, but those lessons may unfortunately be learned too late.

Lynn Frank is president of Utility Systems & Applications (US&A) which designs, installs, tests, calibrates, and evaluates electric metering installations for utilities, corporations, and public agencies nationwide. Mr. Frank can be reached at US&A, 2522 19th ST SE, Salem, OR 97302; phone: 503/315-2293; fax: 503/315-4969; or e-mail: LynnDFrank@aol.com.