Nashville Electric Service (NES, Nashville, Tennessee, U.S.) had an expensive problem. After spending more than US$1.9 million in 1998 to collect beginning and end-of-service reads from the 80,000 apartments in its service territory, it was obvious the utility had to do something to bring down the cost of turn-ons and turn-offs.

NES turned to advanced metering technology, with results that have transformed its operations and established a foundation for a successful future.

NES knew that if it could accomplish its meter-reading objectives in these complexes, the benefits would trickle down to customer service. After all, customers who receive an accurate bill are not only happier but more likely to pay their bills on time, which enables revenue certainty for a utility. Fewer complaints means less call center traffic, reducing costs even further.

Finding a Spot Solution for AMR

NES scoured the market looking for the best available technology solution to meet its objectives, ultimately settling on the MicroNetwork from Itron (Spokane, Washington, U.S.).

The MicroNetwork is a low-cost drop-in network meter-reading system that combines radio and telephone communications technology to collect daily, weekly, monthly and on-request reads from groups of electric, gas or water meters that are isolated, difficult to access, expensive to read, or that require more frequent and unscheduled reads. The system uses existing public telecommunications networks for the transfer of data. In fact, the MicroNetwork's innovative combination of public and private communications network architecture is the model upon which Itron based its new advanced functionality Fixed Network 2.0, enabling fixed network technology to be much more flexible, scalable and cost-effective for strategic deployments.

There are three main pieces that make up the network. The most basic component is the Itron 45 Series ERT, which is installed on each meter and encodes, records and transmits consumption information. The second piece is the concentrator unit, which collects information transmitted from the ERT, stores it and then transfers it to the host processor. Typically, depending on the size of the meter population, a series of network concentrator units each read a set of meters and send the information they've collected to a base concentrator, which performs the final data transfer. The third piece of the MicroNetwork puzzle is Itron's MV-RS meter-reading software, which serves as the host processor.

Meters Connected to MicroNetwork.

Installed MicroNetwork System
Apartment Complex	Number of Meters	Date Retrofitted
2131 Apartments	426	3/1/01
Piccadilly Apartments	817	5/1/01
Executive House	401	5/1/01
Knob Hill	482	7/7/01
Richland Hills	250	8/14/01
Brentridge	351	9/19/01
Iroquois	392	9/24/01
Nottingham	209	10/26/01
Lake DeVille	192	10/26/01
Polo Park	467	10/26/01
Brandywine	663	11/12/01
Bell Hollow	389	11/12/01
Preakness	275	11/13/01
McMurray Manor	331	11/14/01
Rivergate Meadows	213	2/6/02
White Oak	282	2/6/02
Rio Vista	333	2/15/02
Berkshire Place	223	2/27/02
Burning Tree	296	2/27/02
Lodge North	192	2/15/02
Bavaria	211	4/12/02
Highland Ridge	273	5/20/02
Huntington Park Manor	201	5/3/02

After settling on a technology solution, NES needed to test it, choosing a particularly troublesome 426-unit apartment complex to find out what the network could accomplish. For one thing, obtaining reads at the complex was extremely difficult, due to the prevalence of trees, undulating terrain and a stucco finish on all of the buildings. In fact, it was the most difficult reading environment NES could find.

The other reason the complex represented an ideal test site was monetary; the costs were staggering. In 1998, a high turnover rate resulted in more than 1500 visits by NES personnel to the complex for the purpose of gathering turn-on and turn-off reads. The price of such visits adds up in a hurry. The total bill to meet this one site's off-cycle meter-reading needs came to more than $28,000 that year.

Itron and NES personnel implemented the MicroNetwork over a three-day period in November 2000, installing an ERT module on each electric meter in the complex, and setting up two concentrator units, a network concentrator and a base concentrator affixed to a light pole. The setup worked seamlessly, with the ERT modules recording, encoding and transmitting meter tamper and consumption data through the network concentrator and on to the base concentrator. The data was sent daily via a cellular communications link to the MV-RS host processor installed on a computer at NES's metering facility. The network concentrator is mounted to a streetlight.

Since the system began operation, NES meter readers have not had to visit the complex. While NES expected this, it was surprised at the minimal network investment with the difficult reading environment. The utility assumed it would need at least three network concentrator units plus a base concentrator to collect and transfer consumption, and tamper data from the meters. As it turned out, one concentrator, in addition to the base concentrator, was able to fulfill the metering needs at the apartment complex. The RF performance of the signal-sending unit was outstanding.

Now, NES wanted to focus on simplifying its billing process and establish interconnectivity between the billing and meter-reading operations. To accomplish this, NES worked on an interface program that would move energy consumption data from the MV-RS host processor directly into its mainframe billing system. After two months of running the interface in parallel with its mainframe system, NES succeeded in billing all 426 meters at the apartment complex with the newly created program. The utility can now automatically bill every single meter in the complex.

Payback in Less Than 15 Months

From the beginning, of course, the utility's biggest problem and, therefore greatest need for the MicroNetwork, was the cost associated with obtaining beginning and end-of-service reads from the test complex and elsewhere. To that end, NES also installed MV-RS in its reconnect/disconnect section, with its personnel using the software to gather those reads remotely from the complex, never having to send a meter reader to the site to manually inspect each meter.

Based on the utility's reduced meter-reading costs alone, the MicroNetwork system, which was implemented at the test apartment complex at a cost of $34,000, paid for itself in less than 15 months. All ongoing savings go directly to the bottom line.

When it became apparent that the test project was going well, NES installed MicroNetworks at 21 additional apartment complexes. It is now reading more than 7600 meters with the system.

NES averaged 367 turn-on and turn-off work orders per month between August 2001 and July 2002. That equates to more than 4400 such work orders over the course of a year, at a cost savings of approximately $70,000. The utility's communications costs are also minimal. It makes one nightly call during off-peak periods, and cellular costs are less than $15 per month per complex.

What NES has been able to accomplish thus far is merely the beginning. There are eight apartment complexes in its service territory that already have ERT modules installed on all of the meters and are simply awaiting the installation of concentrators and cell phones. In all, NES has budgeted for the installation of a MicroNetwork at 18 complexes and up to 10,000 meters by the end of the 2002 fiscal year, and up to 7500 additional meters by the end of the 2003 fiscal year.

MicroNetwork technology has created the possibility of other future benefits, such as tamper detection, interval and time-of-use data collection and load profiling. NES is also considering the implementation of MV-RS software in its customer service center, which would put precise meter data at its customer service agents' fingertips, providing them with better information for assisting customers over the phone.

In addition, NES is in discussions with its regional gas and water utilities to share meter data, which would reduce costs for all utilities involved. Such an initiative would be much more difficult without the network.

NES has proven the many operational and strategic improvements are possible with advanced metering technology. Though the initial phase of the project has exceeded expectations, NES is certain the best is yet to come.

Eddie Andrews' career spans 34 years with Nashville Electric Service, where he is acting vice president of construction and maintenance operations. Previous duties include operations manager of system operations; meter services manager; supervisor of the technical support group of meter services; system manager of utilities SCADA system; and engineer in the system control section. Andrews presently serves as president of the Mid-South Electric Metering Association. He holds a BSEE degree from the University of Tennessee and an MBA in management from Kennedy-Western University. Andrews can be contacted at eandrews@nespower.com.

About Nashville Electric

NES is a public electric utility serving roughly 287,000 residential and 40,000 commercial and industrial customers over a 700 sq mile (1813 sq km) area in middle Tennessee. Apartment complexes are among the most challenging aspects of its meter-reading operation. With so many residents moving in and out on a regular basis, the costs and resources required to track consumption and bill precisely are significant. The utility's goal was to find a better, cheaper and more efficient way to gather meter readings from these customers, and to do so with greater accuracy than ever before.