Extending Connectivity to the Grid Edge: Importance of Private LTE and 5G

The electric power sector is transforming rapidly. U.S. utilities contend with a growing portfolio of decentralized and intermittent energy resources. They also face challenges with stagnant demand, a range of new technologies, consumers whose interactions with other industries have accustomed them to a higher level of service and responsiveness, and competition from outside firms.

This new market context requires utilities to depart from the traditional focus of energy asset ownership and commodity electricity sales toward a "beyond energy" integrated services and technology-based business model. Industry 4.0 applications will be vital for utilities to remain secure and competitive. Such applications depend significantly on advanced communications networks, and include the following:

Advanced analytics

Intelligent automated devices

Real-time control

Ubiquitous sensing

Cloud connectivity

Edge computing

So, where do power and utility companies, striving to modernize, focus their attention? The answer for many involves extending their connectivity to the grid edge through secure wireless means.

5G and Advances in Future Connectivity

For future connectivity, network advances are an ongoing endeavor. 5G mobile broadband services are the latest hype. This high speed, low latency wireless cellular network will play a crucial role in connecting large quantities of sensors and smart devices. It will also enable leading-edge technologies such as Ultra-HD (4K) streaming, self-driving car connectivity, and virtual/augmented reality (VR/AR) enhancements.

Beyond 5G, new cellular technologies are emerging that are specifically designed to support internet of things (IoT). Lower power wide area (LWPA) wireless technologies, like Cat-1, LTE-M, and NB-IoT, are offering utilities the opportunity to economically connect a wide array of network devices for metering and monitoring purposes. What makes LPWA options attractive is their lower price, their long battery life (10 plus years), and their typically better reach into buildings or basements. In addition, the incremental improvements that brought these advanced versions of LTE (like small cells, carrier aggregation, and IoT interoperability) will pave the way for a smoother introduction of 5G.

The Need for Private LTE

In addition to the newer LPWA technology options, utilities have a growing interest in licensed or shared spectrum options, potentially for the deployment of private 4G LTE networks. Private LTE can be viewed as a utility building its own private cellular network within its territory and using it exclusively for the backhaul communications of distribution supervisory control and data acquistion (SCADA), distribution automation, advanced metering infrastructure (AMI), distributed energy resources (DERs), and other field applications. The advantages of private LTE include the following:

The ability to manage to the desired reliability and security level while building coverage to meet utility needs.

More control over the product lifecycle.

Economy of scale by reducing the number of disparate networks to manage.

Selection from several standards-based LTE endpoint manufacturers, which allows for a more plug-and-play environment.

Potentially lower maintenance costs compared with a variety of other communication alternatives.

Recognizing these benefits, the Federal Communications Commission (FCC) adopted a notice of proposed rulemaking in 2019 that would allow a broadband allocation at 900 MHz. The rulemaking will reconfigure the band from its current narrowband-only allocation and open up the possibility that the band could support private LTE in addition to private two-way radio systems. Currently in the final stages of approval, the rulemaking offers utilities an opportunity to optimize their wireless networks so they are both interoperable and future-proof. To achieve this, utilities should standardize on LTE technology and on the spectrum band in which it is deployed.

Combined with built-for-purpose equipment, the availability of the shared access 3.5 GHz band in the United States will enable utilities to deploy and operate a private LTE network. The 3.5 GHz shared access band, known as Citizens Broadband Radio Service (CBRS), is making 150 MHz of spectrum available on a lightly licensed, shared access basis using a three-tiered model. Tier 1 is used by incumbents such as the Navy, Department of Defense, and by military satellites. The two lower tiers are allocated for commercial use. This spectrum-sharing model will be administered by one of five companies chosen by the FCC to be Spectrum Access Systems Administrators: Federated Wireless, Google, CommScope, Amdocs, and Sony.

The CBRS band will allow a wide range of companies (including utilities) to develop, build, and operate their own wireless networks without being beholden to a wireless carrier. While companies have been able to establish their own WiFi networks for years, if they wanted to use cellular networking technologies like LTE, they had to use a network owned by a mobile network operator. The FCC will auction CBRS licenses beginning in June 2020, called Priority Access Licenses, which may be of interest to some utilities. Others will still be able secure General Authorized Access to the CBRS spectrum, enabling them to build and operate their own private LTE networks at their facilities and other locations without needing a license from the FCC, which was previously a significant barrier to entry.

NaaS Model for Electric Cooperatives

While integrating LPWA solutions and owning a private LTE network are of increasing interest to investor-owned utilities, the large upfront capital outlays required are likely to be prohibitive for smaller utilities such as electric cooperatives. Electric cooperatives interested in LPWA technologies should consider options in a network-as-a-service (NaaS) model. The NaaS business model delivers virtual enterprisewide area network services on a subscription basis. One example is Verizon’s Grid Wide Utility (as a service) solution, which includes integrating smart meters with Verizon 4G LTE Category 1 and M1 smart meter communications device. The solution also integrates smart meters with Verizon's 4G LTE network, security, and a range of cloud-based applications to support smart metering, demand response, meter data management, and distribution monitoring and control — the latter of which has gained traction among electric cooperatives in recent years.

Dakota Valley Electric Cooperative provides electric power and energy to roughly 4200 rural members. In 2017, Verizon partnered with the cooperative to implement a pilot program with 200 smart meters in areas that were typically plagued with poor cell service or unreadable power line communication meters. During this pilot period, Dakota Valley Electric Cooperative achieved 99.99% reliability on meter reads, which was one of its primary goals for the test. Verizon Grid Wide Utility Solutions also enabled the cooperative to improve its operations in several other ways. Instead of having to send out a truck to patrol miles of line trying to manually troubleshoot a problem, the Verizon Grid Wide platform automatically sent alerts with the information needed to pinpoint and assess issues, vastly improving the efficiency of truck rolls.

In addition, Peninsula Light (PenLight) in Washington State announced in 2019 it will use Verizon’s platform to manage smart meters for its more than 33,000 customers. This includes managing everything from standard billing and remote connect-disconnect applications, to more advanced outage detection and grid monitoring. Moreover, Verizon has been making its Grid Wide software development kit available to vendors and utility partners, enabling them to create their own applications on top of the platform.

The Path Forward

In the past, utilities viewed communications networks as a compulsory cost of doing business. Those days are over. Utility modernization requires a communications network that is foundational to the delivery of safe and reliable service to customers, today and in the future. As an increasingly complex grid depends ever more upon data, the communications network becomes one of the utility’s key strategic assets.