Analog versus Digital Smart Electric Meters

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The basic purpose of electric meters -- analog or digital "smart" meters -- is to measure how much electricity is being used in a residential or commercial building. Such meters provide data on the amount of electricity used to run lights, heating and cooling systems, appliances and other electricity-powered devices.

Analog Meters: Basic and Time-Tested

Analog electric meters are useful for monitoring electricity use on a periodic basis and for checking the accuracy of electric bills from month to month.

Analog meters have multiple spinning dials, which are best read by qualified electricity company representatives. These types of meters can be confusing for average consumers to read because the hands on the five dials alternate directions: The first hand revolves in a clockwise direction, the second counterclockwise, the third clockwise and so on.

Analog meters have one purpose: To tell the consumer or meter reader how much electricity has been used since the last reading.

Smart Meters: Multifunctional and Interactive

Digital or “smart meters” record daily electricity use and share information about consumption between users and electricity suppliers over wireless digital radio frequency networks.

A home energy management system with compatible, interactive devices connected to an advanced metering infrastructure (AMI) has potential energy management benefits. For example, smart meters may one day enable consumers to program electricity use for non-peak hours when power is available at a lower cost.

This interactive capability could also allow utility companies to manage energy use and adjust loads during periods when there is danger of a potential system overload such as during periods of extremely hot or cold weather.

Consumer Concerns About Smart Meters

Some individuals are concerned about potential problems with the smart meters that are part of advanced metering infrastructure (AMI).

Health activists, consumer watchdogs, and privacy advocates have raised three main areas of concerns:

  1. Consumer watchdogs question the accuracy of smart meters and the likelihood of billing errors.
  2. Health advocates are concerned about potential risks related to the effects of low-level radiation, which is produced by the smart grid’s wireless radio frequency network. This issue is similar to the controversy regarding cancer and the use of cellphones.
  3. Privacy advocates are worried that information gathered by smart meters and other smart grid devices will be misused.

Questioning Smart Meter Accuracy 

Customers sometimes file complaints about inaccurate smart meters when they receive higher-than-usual electricity bills. Though a smart meter may be faulty, other variables could be to blame. Billing cycle changes, extreme weather conditions, higher consumption, faulty home appliances or heating and air conditioning systems can result in high electricity bills. Dynamic energy pricing also can cause fluctuations in electricity consumption, notes a report by the Electric Power Research Institute.​​

Key Cases on Smart Meter Accuracy

The two highest-profile cases involving customer complaints of inaccurate meters were in California and Texas.

When customers complained of higher bills after smart meters were installed in parts of those states, authorities ordered independent audits of the meters. The complaints coincided with a hot summer in California and a cold winter in Texas, conditions which may have contributed to the perception of inaccuracies.

Hot Under the Collar in California

San Francisco-based PG&E began installing smart meters in its service area in 2006. In 2009, the utility company began receiving a flood of complaints about unusually high electricity bills, with customers blaming the increase on faulty meters.

In October 2009, the company informed customers that the higher bills were not the fault of the meters, but due to the increased amount of electricity needed to run air conditioners during the unusually hot summer.

Two rate increases also increased consumer electricity bills that year.

Nevertheless, in May 2010, PG&E apologized to customers, primarily for poor customer service. By the time PG&E issued the apology, it had installed 5.5 million smart meters in its service area. The investor-owned utility company said at the time that less than 1 percent (50,000) meters had malfunctioned.

Results from an independent audit of smart meter devices ordered by the California Public Utilities Commission were released in September 2010. The audit ultimately showed that the 750 smart meters tested were accurate and that customer billing matched expected results.

Winter of Discontent in Texas

In 2010, Texas utility company Oncor received a flood of complaints about the accuracy of its smart meters, prompting the state's utilities commission to hire independent analysts to confirm their accuracy.

At the time, Oncor said the increase in complaints was not only from smart meter customers, which numbered about 760,000. Most of the billing complaints came from customers with electromechanical meters. The company said the increases were likely due to the unusually cold winter.  Nevertheless, the Texas Public Utility Commission responded to requests from legislators and consumers for independent verification of smart meter accuracy. In July 2010, Oncor reported that only 25 of the 1.1 million smart meters it had installed were inaccurate.