The transition from power-line carrier

As technology companies pioneered new mobile applications such as email and web browsing on phones and tablets in the early to mid-2000s, electric cooperatives were adopting their own technology innovation: power-line carrier (PLC). This new way of transmitting metering data enabled utilities to receive data daily using the same infrastructure that provided power to their members. This meant technicians no longer had to walk from house to house to read meters, reducing the need to brave inclement weather and unruly pets.

But, as they say, time stops for no one. As smartphone technology has continued to evolve in response to changing customer requirements, so has metering infrastructure. The world has become increasingly reliant on real-time connectivity and data, so new solutions have been called on to help co-ops stay ahead of the curve. A variety of new applications and technologies are available for co-ops to serve their members better—advancements that also are opening the door to smart utilities and smart city initiatives. By upgrading from PLC technology and embracing these advancements, co-ops are paving new pathways to productivity.

Advanced Communication Networks

As the advanced metering infrastructure (AMI) landscape has evolved, it has become quite evident that wireless communications can be the pathway for delivering new benefits. This change requires co-ops to transition away from PLC to position themselves for future success.

Even so, multiple options exist for wireless communication networks within the AMI framework. One of these is mesh, a system in which radios communicate with each other, with messages hopping from meter to meter. Each point on the network can receive, store and transmit signals to other network points in many different directions. This network system architecture blankets an area with coverage and offers some redundancy in the case of problems. However, mesh networks use unlicensed spectrum for their communications and operate on public radio frequencies, which run the risk of interferences because they are available for anyone to use.

Another option is using point-to-multipoint communications systems, which can enable the co-op to transition its system using a Federal Communications Commission (FCC) primary-use licensed spectrum. Combining these networks with smart meters enables better connectivity and smart infrastructure for the co-op. With this architecture, a collector — or base station — communicates to many end points directly within a large coverage area. These endpoints are frequently meters but also can be load control modules, lighting modules or distribution automation endpoints. Before installing a point-to-multipoint system, a propagation study is used to determine optimum base station deployments for maximum per-formance. This network design is ideal for many different topographies but particularly excels in rural areas.

By operating on licensed radio-frequency (RF) spectrum, point-to-multipoint systems can transmit much farther than mesh, with twice the transmitting power of a system operating in the public frequency band. With this network design, the increased range enables each endpoint to communicate directly with a base station without having to hop from endpoint to another endpoint to send data back to the headend software. The point-to-multipoint design also dramatically reduces the number of times an end point must transmit data to the co-op. Point-to-multipoint endpoints only need to communicate a few times a day.

Even More Options

Point-to-multipoint systems also can listen and send messages at the same time, making them true two-way networks. And, because licensed RF spectrum networks are private, each co-op is assigned a RF bandwidth range only it can use. These licensed RF channels are protected by federal regulations, and interference can be mitigated quickly and efficiently with the full backing of the U.S. government.

In a PLC network, outage information is compromised when the distribution network is disrupted — when a pole is down, for instance. Because meters have a last-gasp capability, point-to-multipoint architecture enables a much higher outage success rate. Each endpoint transmits a power outage message to the network without having to rely on a neighboring endpoint’s communications path to the takeout point. During outage and power restoration events, utilities with point-to-multipoint architecture have experienced a 33% reduction in service restoration times because of the increased amount of useful outage information.

As a network architecture solution, a point-to-multipoint system can support today’s applications as well as new functionalities, data rates and capacity — all on the same system. Moreover, by supporting every generation of product and solution on one network, existing assets can continue to be used while new technologies are being implemented. Utilities should not have to go back to their commission, city council and members to request funding for new applications. Instead, they can build business cases around the new endpoints and applications they would like to deploy on the existing network.

Making the Move

Comanche Electric Cooperative Association services seven counties and 5000 miles (8047 km) of power line in North Central Texas, U.S. This vast rugged landscape serves as a playground for hunters and outdoor enthusiasts, but it is no walk in the park for the co-op to provide dependable services to customers. Generating and distributing power can be a tricky business in the rural Texas terrain. On top of this, sending out technicians to collect and analyze data from more than 17,000 meters with such diverse terrain can be challenging.

After more than a decade leveraging a PLC system for electric metering, Comanche Electric Cooperative decided it was time to usher in a new era of innovation to support its growing base of approximately 9000 members. Although the PLC system had served the utility well historically, challenges had begun to mount over the years. Meters were getting older and experiencing power quality issues. It was becoming increasingly difficult for the co-op to make necessary repairs and updates to the aging infrastructure.

Furthermore, the amount of time it took to get data from all the meters in the field was unsustainable and Comanche Electric Cooperative was aware technologies were available that could speed up the processes. The co-op decided it was time to make a move.

While Comanche Electric Cooperative’s aging PLC system could no longer support member needs, it did offer the framework for a seamless transition to AMI. The co-op searched for a point-to-multipoint network solution to deliver data over diverse terrain, improve operational efficiency and reduce the number of trucks in the field.

After a successful pilot program with the Sensus AMI solution, Comanche Electric Cooperative moved forward with full deployment. The co-op’s AMI system included the Sensus iConA Gen 3 electricity meters connected to the headend system through the point-to-multipoint FlexNet communication network. Enabling the quick transmission of usage data over a secure, reliable two-way network, the solution gave the co-op the visibility and control it needed to manage its metering system proactively.

With real-time data provided by the AMI system, Comanche Electric Cooperative could streamline its outage management process and offer a superior level of service to customers. The solution also freed up staff time, making it more efficient across operations by adding advanced capabilities such as disconnecting meters remotely.

Smooth Transition

In an evolving smart technology landscape, co-ops might be trying to decide what is the best approach to transition from PLC to AMI. It all begins with choosing a flexible solution, one that can be deployed and upgraded on a co-op’s unique timeline.

Because it chose to deploy a scalable point-to-multipoint system, Comanche Electric Cooperative managed its AMI deployment and new meter installations over a two-year span without disrupting existing services or capabilities. The co-op reviewed current processes and adapted them to the new system in an organized manner with a systematic and controlled approach during rollout.

By deploying a communication network strategically to overlay existing infrastructure, Comanche Electric Cooperative could install new meters anywhere in its service territory without affecting current operations.

In addition to improving operations and customer service, Comanche Electric Cooperative’s AMI system enabled the utility to roll out new applications and advance on its own timeline. The co-op was able to install meters, assess new deployments and manage it all while everything remained connected across its technology infrastructure. With this system, the utility could be strategic in its approach—adding new features and functionality on a schedule that made the most sense for the co-op.

As its requirements evolve, Comanche Electric Cooperative’s network architecture provides the capacity for advancement as the industry continues to progress with the introduction of new applications and smart technologies. Capabilities for demand response, distribution automation and smart lighting all are supported possibilities. So, as the utility looks to expand in response to new customer demands, it will be in a good position to answer the call.

Blueprint for the Future

Early PLC adopters like Comanche Electric Cooperative received exactly what they were looking for when they originally launched their system: automated meter reading. However, times have changed and there are new challenges — and opportunities — that PLC systems struggle to handle. Many co-ops today demand real-time visibility into sensors and meters. This influx of data enables more efficient control of the complex modern grid while also providing a more resilient infrastructure.

By committing to a PLC migration plan, co-ops can continue their pioneering ways of leveraging data more effectively, streamlining internal processes, and gaining better visibility and control over their distribution network. An AMI system backed by a point-to-multipoint communication network provides the most effective solution for this transition, enabling smooth deployments with little infrastructure build-out and system-wide coverage up front. As utilities continue to advance with smart technology, their AMI system will ensure they are ready to make the migration.

Chad Foreman (cforeman@ceca.coop) is director of information technology for Comanche Electric Cooperative Association, headquartered in Comanche, Texas, U.S. Foreman has been with co-op for more than 12 years and currently oversees all aspects of its information technology and metering systems.

For more information:
Comanche Electric Cooperative | www.ceca.coop
Sensus AMI | https://sensus.com