Wireless Networks for Electric Utilities

Published on
Jun 22, 2023
Written by
Lockard and White
Read time
10 min
Category
Articles

Adapting your wireless network

The electric utility industry today is among the most rapidly evolving industry sectors. New technologies, new priorities and evolving regulatory requirements all contribute to increasing pressure to accommodate new applications and demands that can only be enabled with updated and expanded wireless communications networks. It is critical for utility leaders to stay ahead of the ongoing changes by building a foundation today that meets the expectations and opportunities of an evolving tomorrow, without compromising the commitment to reliability.

Electric utilities have always been charged with the awesome responsibility of keeping the lights on, no matter what. Customers experience inconvenience when Netflix fails, but they potentially suffer from catastrophe when a critical grid fails. Because of that reality, utilities cannot take risks that put their commitment of reliably delivering energy to homes and businesses in jeopardy. When new technologies are deployed, they must perform reliably, even under extreme conditions.

Much has been written about private LTE (PLTE) as the preferred wireless network solution, and for good reasons including capacity, security, and a massive ecosystem of devices and support due to its compatibility with international standards, just to name a few. Those reasons and others make a very compelling argument for PLTE as the right broadband solution for electric utilities, so it’s not difficult to understand why some have already begun designing and deploying those networks with more surely to follow. PLTE is a great solution for utilities, but given their differences due to factors such as ownership model (IOU, municipality or cooperative) density of meters, size of the operating area, spectrum options and availability, does it make sense for all of them?

While we believe all utilities should evaluate PLTE, we also know that the operational and business realities of some, along with the current landscape of options, don’t fit within the constraints all utilities must consider. Many cannot justify or afford to purchase, build, and operate a PLTE network across their entire operating area. For the ones that can’t, will they be left behind, unable to support industry advancements, or is there another path to the future for them? There are other options besides PLTE, and for some power providers, alternatives to PLTE may be better for reasons relating to applications needed, cost and other factors. In some cases, the savvy move may be a hybrid approach that embraces a combination of narrowband and wideband networks to deliver the required wireless results. This paper will describe an approach which we term Heterogeneous Spectrum Layering designed to help those utility network planners understand the traditional options available in an ever-changing environment.

Heterogeneous Spectrum Layering is an approach that maximizes the value of existing investments while building a path to the future and allows utilities to augment existing investments to expand and extend current wireless networks. It is a strategy that can be used for increasing data throughput for a growing number of field data devices by adding network capacity and maintaining the current investment in traditional narrowband systems, when broadband PLTE isn’t the right fit today, but may be in the future. In this way, utilities can make forward-looking investments incrementally to reliably support the need for higher capacity wireless networks and continue to benefit from investments in their valuable assets of narrowband and wideband systems.

Start where you are

Some utilities may be wondering if one or more of their current wireless networks deployed as tools to operate the grid still have value, financial or otherwise, even in this rapidly evolving industry. After all, many have already invested heavily, are currently doing so, or have near-term expansion plans using these same technologies, each purpose-built to do a specific job:

  • Land mobile radio (LMR) networks for line crews and field workers to communicate with dispatch and with each other.
  • Grid-mesh wireless systems to report metering information.
  • Point-to-point or point-to-multipoint wireless solutions to gather data from remote grid-tied DER.
  • Wireless point-to-multipoint networks to gather Distribution Automation (DA) information and Supervisory Control and Data Acquisition (SCADA) information.

Wireless networks of this type are commonplace and characterized by their slow evolution and years of trusted reliability, so the motivation to continue using them is understandable.

What's changing

The landscape for utilities looks different these days, and industry observers recognize that market demands, technologies and regulations will evolve at a more rapid pace moving forward. Changes will come in the form of shifting from central power plants to countless nodes of small generators, electric vehicles and batteries that may allow for controllable and flexible consumption patterns, Advanced Metering Systems, and customer control and usage information demands. In addition, grid operators are increasingly faced with changing mandates from policy makers regarding reliability, digitalization, decarbonization, and more.

Power providers are evolving, both in scale and types of considerations to meet the evolving grid architectures. Changes stress and challenge the supporting wireless networks and the professionals responsible for empowering the growing network capabilities. These challenges introduce uncertainty and create opportunities for the prepared and adaptable. This evolution will continue for many years, so a flexible communications network that can grow and adapt to these transformations is vital.

In 2021, U.S. electric utilities had about 111 million advanced (smart) metering infrastructure (AMI) installations, equal to about 69% of total electric meters installations. Residential customers accounted for about 88% of total AMI installations, and about 69% of total residential electric meters were AMI meters.
— U.S. Energy Information Administration

These changes will define a utility’s future state. The explosion of network attached devices on the grid will bring a deluge of data that must be transported, stored, and managed.  For some, the right answer to keep pace with technology will be an immediate and complete transformation of communications technologies to broadband (1. 4 MHz paired or greater) private LTE based on available solutions, integrated, and managed as a single network. For some, that approach may not be feasible.  For others, it may eventually become an option, but more immediate interim steps may be needed to move in that direction.

The utility push and pull between old tech and new opportunities

As utility leaders seek to usher the electric power industry into the future and establish the sector at the forefront of cutting-edge industries, wireless networks have emerged as critical pieces of that objective. They have become essential to modern utility operations and highlight the need for effective and efficient use of limited and expensive spectrum.

Today, an increasing number of forward-looking utilities are considering broadband wireless access technologies like PLTE for connecting their growing number of operationally important field devices but decision makers at utilities where PLTE doesn’t make sense may feel that the use of existing narrowband and wideband networks doesn’t give them a way to support initiatives that demand increasing wireless network capacity. They may be thinking they must choose between opposing technology pathways: new vs. old, and which will receive finite available investment funding. Specifically, narrowband networks that are established as critical wireless communications or starting from scratch with a broadband private LTE solution. There is no single ‘right’ answer for all utilities.

However, answering the question posed is inherently accepting that this question is the right one to answer. In fact, creative and innovative opportunities abound for some utilities that recognize that they can leverage current and pending investments in narrowband and wideband systems while leaning into the future of increasing wireless demand at the same time, without missing a step.

A more viable solution is a combination of networks operating on narrowband (12.5 or 25 kHz) and wideband channels (everything between narrowband and broadband). Changes to these networks done incrementally may provide more flexibility while still being capable of meeting the utility’s needs for many years. These utilities could always explore broadband should requirements change down the road, and can feel confident that a layered solution will integrate into that future state.

In the paragraphs that follow, we will outline a path forward using the concept of Heterogeneous Spectrum Layering. A strategy that combines the best of both worlds: leveraging existing infrastructure investments while incrementally layering on additional narrowband and wideband spectrum and technologies that allow utilities to take advantage of new wireless network capacity and flexibility to serve changing and growing needs.  

How is the future story being rewritten using existing technology?
Consider Heterogeneous Spectrum Layering

Due to the unique regulatory constraints placed upon utilities, grid evolution has historically been gradual. Conservative decision-making has long been a baseline approach to minimize rates and avoid investments with excessive risks and deliver power reliably and efficiently.

Today, in addition to rapid technology advancements, regulators and legislative bodies are pushing for grid resilience and user protection from outages. This environment requires utilities to move more swiftly to implement new technology solutions in the grid. Utilities must minimize customer rates, which is why abandoning recent investments for newly available broadband networks isn’t necessarily a prudent choice.  Conversely, it is inadvisable to overlook technology solutions that enable optimal grid operations.

This push and pull between today and the future state of grid communications is why this paper argues for a ‘best of both worlds’ approach. This strategy adds a ‘wideband’ layer (up to 1.3 MHz, paired) on top of an existing narrowband layer (≤25 kHz, paired) to address the need for increasing wireless bandwidth. With Heterogeneous Spectrum Layering, some utilities need not abandon the valuable investments of their existing networks to deliver the required wireless results.

Determining whether this strategy is right for a given utility requires close attention to, and a thorough understanding of the available options along with careful planning to create a roadmap to the network of the future. The regulatory environment, economic factors, projected grid needs, technological developments, and the maximization of current investments must all be assessed and considered.

Numerous utilities have already made investments that reflect this approach. For example, at least 21 utilities have invested in 700 MHz A Block wideband spectrum to augment their existing narrowband spectrum holdings adding wireless capacity incrementally to address the increasing need. These wideband additions combined with the utilities’ existing narrowband networks result in multiple narrowband and/or wideband networks, with overlapping layers providing broad coverage and capacity to deliver the required wireless results without the need for broadband spectrum and the expense of a single, multi-service broadband network.

Charting a course with Heterogeneous Spectrum Layering

Meeting the projected timing and scale of DA and DER growth and the need to monitor and control those technologies (whether with AMI or the next generation of tools to deploy sensors and other nodes/devices on the grid) makes flexibility and efficiently ramping up wireless capacity a priority. Furthermore, the process must be completed without sacrificing reliability, data throughput, security, or affordability to the remote devices or network services. By setting the stage in that manner, the next phase of the journey can be difficult for utilities that do not have sufficient resources available. The benefits will exceed the costs if the grid upgrade is correctly planned and implemented, but a clear roadmap is vital before moving forward with deployment of additional wireless network capacity.

Maximizing existing infrastructure while building a path to the future

While the right path to the future may appear long and difficult, a spectrum layering approach may provide some relief because it doesn’t require starting from scratch. Existing narrowband infrastructure may have significant remaining value for years to come and can continue to play a critical role in the wireless network future without sacrificing the reliability of utility-critical services.

Utilities with existing narrowband or even wideband wireless networks will likely still have challenges to overcome. Regardless of past investments or how much perceived life or value remains in legacy systems, near and long-term expenditures (capital and expense) will likely still be required to satisfy ongoing grid communications growth needs.

In one specific example, a prominent utility that implemented this strategy made the strategic decision to use the spectrum layering approach after evaluating all pathways forward for wireless network upgrades, and finding PLTE was too great of a stretch. After careful consideration, the right decision was determined to be selective investment in narrowband and wideband spectrum along with network equipment upgrades for voice and data. The costs associated with broadband infrastructure and spectrum leasing or purchases sufficient for PLTE were deemed to be too high when compared with the alternative approach of spectrum layering. In this example, the right decision for the utility was continued use of narrowband and wideband networks. However, they intend to reconsider high data throughput or LTE systems when plans for the development of the current systems show that it cannot accommodate future goals.

Where does narrowband come into play?

Utilities evaluating all the options may be asking, what is the role of narrowband spectrum in the future state? Looking at some of the common narrowband and wideband technologies, each has its own use case and the ones that can operate as part of a Heterogeneous Spectrum Layering strategy are particularly compelling.

Increasing wireless capacity with wideband: Example using 700MHz

While numerous bands are viable options, the 700 MHz Upper A Block is one specific example of wideband spectrum that can be used for critical infrastructure networks by companies that have defined a need for wireless capacity today beyond what narrowband can offer. Multiple manufacturers offer systems that support various use cases including SCADA, Distribution Automation (DA), remote site communications, and other voice and data applications in the grid, including LMR.

The ongoing development of applications for this band provides a lesson in the dynamic nature of technology. Manufacturers are adding capabilities that increase the speed and lower the latency on wideband spectrum. Utilities that have narrowband (such as 220 MHz) that add an investment in 700 MHz or other wideband spectrum solutions are achieving new capabilities that were not available with their existing technology just a short time ago.

Taking the next step of Heterogeneous Spectrum Layering: Approach with diligence

Is a spectrum layering strategy right for your utility, or should it be PLTE? Perhaps a short-term spectrum layering strategy with a transition to PLTE over time makes more sense. For many utilities, the answer may not be obvious and might only emerge after careful analysis and consideration of many dynamic and complex factors. If the right path forward begins with spectrum layering, when and how do you take the first step?

The distance of the ‘first step’ is not a barrier because it’s just a step. A misconception unduly persists that there is no ‘gradual’ first step for increasing wireless network capacity, but many utilities do not possess the precious time or corporate skillset to navigate the variety and depth of choices facing them on the path to the future. Utilities can take a first step with confidence if preparation and thoughtfulness are part of the evaluation and implementation plan.

First step: Identify a Spectrum Layering strategy

The right spectrum layering strategy for any utility will be specific and driven by its unique circumstances including the status of its legacy narrowband and wideband networks, customer demands, availability of spectrum across its operating area and the business plans. The first step is determining how much spectrum will be needed in the short and long term, to support each use case. Only then should the other considerations be factored in, the appropriate strategy established, and plans developed.

Deciding on the path forward for your utility is not an either/or decision between broadband and no man’s land. The company may have invested millions on spectrum at 900, 220 or 450 MHz, which is valuable and could continue to be part of the spectrum portfolio. Heterogeneous Spectrum Layering simply enables the maximization of legacy network investments while forming the cornerstone of the wireless network future in a way that makes sense for each utility’s budget, resources, and timeframe.

While that approach will likely still require buy-in and investment in additional spectrum, it does not require starting from scratch. However, delaying the investigation and acquisition of additional spectrum may lead to increased costs and less than optimal solutions since spectrum is a finite resource. Utilities may want to consider that for nearly the last decade, narrowband and wideband spectrum available to utilities has been stable or declining. In comparison, for broadband spectrum, withing the past few years, CBRS (3.5 GHz), 900 MHz and Band 54 (1600 MHz) have become available to utilities, and other broadband license bands may soon become available to utilities also.

Conclusion

The risk of doing nothing leaves a utility unprepared, and it is important for utilities to align their IT/OT organizations to map out the future impacts from initiatives such as decarbonization, where an increase in connected devices is highly expected. Having access to more bandwidth and spectrum to support these connected devices is a key part of a growth and de-risking strategy, and exploring the additional bands to support a future roadmap is essential, as spectrum is a finite resource.

A layered spectrum approach isn’t right for every utility any more than PLTE is, so where might PLTE outshine a layered approach? Utilities that have already determined PLTE is right for their needs often cite the benefit of reducing the number of disparate networks at various bands layered together, using multiple equipment vendors to accomplish what a single PLTE network can deliver. The efficiency and simplicity of a single, holistic broadband network should be an important consideration in complex network environments, especially in dense urban areas with lots of devices.

PLTE is the right choice for some, but not all, so how do you know if it’s the right answer for your utility? If it is, what spectrum should be used? Due to its many benefits, utilities should give careful consideration to PLTE, with the understanding that the effort may result in a finding that there is a better alternative capable of delivering a robust system that fits a long-term modernization strategy, right sized for the needs.

For those that decide now is simply not the best time to step into broadband wireless, Heterogeneous Spectrum Layering is an alternative way to prepare for that future today and make decisions about networks and spectrum while maximizing investments in current networks without the fear of being left behind. The beauty of this approach is that it does not preclude utilities from exploring PLTE in the future.  A layered wideband and narrowband network could be the appropriate solution for a utility’s needs today, but can also become part of a larger holistic broadband PLTE network down the road, should future requirements lead toward that type of solution. For help making such a critical strategic decision, we recommend utilities seek assistance from other industry experts to review the leading technologies and available spectrum options and help determine what is best for your enterprise.

Lockard & White

Whether it’s a combination of narrowband and wideband using spectrum layering, or broadband P LTE, L&W will deliver unbiased recommendations based solely on what’s best for the utility, deliberately developed according to a purpose and plan on carefully selected spectrum using a proven approach:

  • Evaluation of needs
  • Current state assessment of wireless communications networks
  • Identification of the desired future state
  • Network strategy development including consideration for broadband PLTE and narrowband / wideband spectrum layering

Whether it’s support for grid modernization, Distributed Energy Resources (DER), electric vehicles, or many other initiatives, it’s clear that a transformation is taking place in the electric utility industry today, accompanied by a requirement to communicate with the countless devices that will make up the grid of the future. The industry is primed to benefit from broadband wireless networks and shows no signs of slowing down, but not all utilities are the same and their use case priorities are just as different. Given that amount of variation, the right wireless network solution for a given utility is not obvious.

Lockard & White has built its reputation helping clients make important decisions about purpose-built private networks for critical infrastructure without bias and stands ready to help utilities collaboratively assess their current and future wireless network needs. We welcome the opportunity to discuss our analytical approach that includes both engineering and business considerations to determine the best wireless network solution for your utility.

Need help choosing the right path? Contact Lockard & White, today!

Want a copy of this white paper? Email info@landw.com to request the document.