Electric meter technology has evolved over the years. The original style of residential meter used an intricate set of gears and coils to accurately measure the amount of electricity being used. Many will recognize the horizontal flat spinning disc under a glass cover that measures electricity usage in kilowatt hours (kWh) as gears rotate the numbers on the meter register. This meter does not have the capability to communicate information.
PIE&G still has many older electro-mechanical meters in service. Although highly accurate and reliable, the drawbacks are that someone must read the meter, write down the reading, and manually input the reading into a billing system – a process both time intensive and susceptible to human error. In addition, as with any mechanical device, with age, electro-mechanical meters eventually slow down over time and must be calibrated to remain accurate. All electro-mechanical meters inevitably reach a point where they stop registering energy usage (a “stopped” meter) and can no longer be calibrated. They cease to operate, which is confirmed by a meter test, and must be replaced.
All meter manufacturers stopped producing electro-mechanical meters in 2009 as newer technologies developed and as utilities transitioned to digital meters.
The next step in the evolution of the electric meter came with digital meters. PIE&G currently uses digital meters that do not communicate. The meter measures the electric consumption and registers the use in kilowatt hours (kWh) on its index. Since the meter doesn’t communicate, a person is still required to read the meter, record the reading and report it to the utility. The utility must then enter the reading into the billing system. Obtaining meter readings in person is costly, time consuming, labor intensive and prone to human error. If a meter reading is not taken and reported to PIE&G each month prior to the next billing generation date, the bill must be estimated by the billing system based on the member’s prior consumption history. PIE&G is required to obtain an actual reading after a bill has been estimated for three months. PIE&G will then obtain an on-site current actual meter reading. Since the energy usage on the register dates back to the last ‘actual’ reading of the prior estimated months, this often results in a larger ‘catch-up’ billing from the most current actual reading to the last actual reading perhaps several months ago. This is especially true when readings are estimated over the colder, darker winter months, when most people necessarily use more energy to light and maintain warmth inside the home.
PIE&G uses digital non-communicating meters to replace its older electro-mechanical meters that have or are reaching the end of their useful life (approximately 15-30 years). A review of the usage history will indicate that the meter is not properly registering usage. The record will show declining or little to no usage over time due to the meter slowing down or stopping.
AMR – Top View
AMR – Side View
About the same time that digital meters began to be replace electro-mechanical meters, the industry began introducing an electronic module. These modules, sometimes called electronic radio transmitters (or “ERTs”) are attached to mechanical meters and can be mounted on both gas and electric meters. The ERT module reads the rotations of the meter’s dial and captures that data in memory. At regular intervals, this ERT reports consumption data via radio signal to drive by vehicles equipped with mobile meter reading receivers. The data that is collected is then downloaded onto computers at the utility’s office where it is uploaded into the billing system. This advancement eliminates the need for humans to read the meter, reduces human error inherent when readings are manually entered, reduces costs, and provides members with more accurate, consistent billing and usage history. This technology is referred to as an automated meter reading (AMR) system.
The latest meter technology is the all-digital communicating meter which has no gears or rotating disks. Using electronics, the meter measures electricity use in the home, stores the usage data and sends the data via secure radio signal to a collector unit mounted high on communications towers or power poles. The collector in turn, transmits the encrypted meter and usage data to the utility’s office via radio signals (or cellular) and downloads it to computers. AMI helps the utility and the members save money by reducing expenses of sending employees and vehicles long distances to each service location to obtain meter readings. In turn, the data is timely and more accurate, thereby allowing actual usage to be billed instead of billings with estimated readings. Members can access their energy usage online to review their usage patterns and to better understand and manage their bills.
AMI meters also provide necessary information to help the utility identify power outages quickly, which in turn allows for faster outage response and shorter outage duration.