The rapid emergence of the Internet of Things (IoT) technologies and strategies has captured the interest and imagination of utilities. IoT offers the potential to transform a wide range of grid operations, such as asset management, predictive maintenance, self-healing functions, fault detection, fault localization, dynamic line rating, security, isolated worker protection and much more. But what are the practical implications of IoT for utilities?

The idea of applying IoT to utilities isn’t entirely new; this shift is part of an evolution that is well underway, and in fact, pre-dates the use of the term IoT. Power utilities worldwide are in the midst of significant transformations as they gear up to adapt to new market forces, an evolving regulatory environment and the introduction of distributed renewable energy sources (and the disruptions they bring).

To make their grids “smart,” power utilities need to understand what is happening on all parts of their network, all the time. To accomplish this, utilities need a wide array of sensors and other connected devices deployed throughout their grids to provide various kinds of intelligence. This intelligence can then be used to monitor and optimize grid performance, and ultimately help deliver a better experience to customers.

At the heart of this process are communications networks, which effectively serve as the “central nervous system” of the grid, connecting hundreds of thousands, or ultimately, even millions of sensors deployed throughout their transmission and distribution infrastructure. These sensors, in turn, gather and share information to support rapid and often automated decision making.

To manage the transmission and processing of all this data, the communications network needs to reach much farther out in the grid than ever before, connecting with, characterizing and orchestrating each of these devices. This is the role of the field area network (FAN), which utilities rely on to provide the connections between the multitude of sensors and other connected devices and the "smart" part of the network, where data can be processed, and decisions can be made.

This decision-making capability is particularly critical as utilities seek to address a key challenge created by the rapid introduction of distributed renewables – matching supply and demand to manage the “duck chart,” a curve named after it its duck-like shape. The duck chart documented the timing imbalance between peak demand and the production of renewable energy in California throughout a given day. Essentially, utilities would see a dramatic oversupply of power from solar sources in the early afternoon, but relatively low demand. Demand would then increase dramatically in the late afternoon as people returned from work and school, only to see supply dropping as available solar energy diminished.
 

You might ask what a mismatch between energy supply and demand in California has to do with IoT networks and smart grids elsewhere. The reality is that any utility that is making use of renewable sources is going to face the challenge of how to manage demand in the face of supply that varies dramatically based on time-of-day, weather changes, seasonality and a host of other factors. Real-time insights into the performance and behavior of the grid are essential to managing this challenge. Utilities can use FANs – connected to an extensive and diverse array of sensors - to extend intelligent distribution automation out into the grid, enabling them to match supply and demand more effectively, while maintaining a stable and reliable grid.

How does this work in practice? In one example, utilities can use phasor measurement units (PMUs) to perform synchronized, real-time measurements of remote points on the grid, checking as often as 30 times a second. This is an essential element of any grid-wide stability assessment, and FANs play a critical role in providing the linkages necessary to gather and process the needed data. This, in turn, gives utilities actionable intelligence on the performance of their grid that they can use to optimize operations.

Clearly, FANs play a central role in supporting grid operations, and their importance is certain to grow as IoT strategies mature and build-outs mature. It is important to note, however, that not all FANs are created equal. In fact, historical approaches to FAN deployment to date may actually hinder efforts to support more intelligent distribution models, undermining efforts to make grids smarter.

Over time, many utilities have built individual FANs to support specific applications, often based on proprietary technologies, or perhaps using unlicensed or lightly licensed spectrum. They may have one FAN for line monitoring, another for advanced metering infrastructure (AMI), another again for synchrophasor measurement (assessment of aggregated data from PMUs). In some cases, these FANs were each built using discrete networking technologies.

As a result of this, many utilities have multiple communication network silos that need to be monitored, managed and maintained individually, something that will become increasingly burdensome as utilities deploy more and more new applications. This approach can lead to higher operations and maintenance cost while making inter-operation and coordination between different applications on the grid more difficult, if not impossible – not exactly the "smart" approach.
 

Utilities do have alternatives. One strategy gaining considerable currency is the deployment of a converged FAN based on industry-standard technologies. By using LTE mobile broadband technology, coupled with Internet Protocol/Multi-Protocol Label Switching (IP/MPLS) infrastructure, utilities can move to a truly future-proof network that can address their networking requirements far into the future. Such a converged network can support multiple grid applications simultaneously, providing each with the levels of priority, performance and security tailored to its unique requirements.

In addition to delivering secure, reliable and scalable communications links, this converged network infrastructure can facilitate smooth inter-operation between discrete applications, which can help to make the grid more responsive, which is a key goal of smart grid strategies.

For many utilities, the move from individual silos to a converged FAN is not so much a leap as an incremental step. Power utilities around the world have already begun the transition to IP, with many taking advantage of the benefits of a managed-IP approach by deploying IP/MPLS to support their wide area network (WAN) requirements. By adding LTE to their capability set, they can quickly and seamlessly extend the capabilities of IP/MPLS wirelessly from the WAN to the FAN. In this way, utilities can link up devices in the field with the control and management systems that are already in place in substations and operations centers.

As important, because they are standards-based, these converged networks can also support the evolution of future technologies such as 5G and accommodate popular emerging IoT technologies such as low-power, wide-area (LPWA) wireless access. These networks can also support connectivity over some unlicensed or lightly licensed spectrum such as Citizens Broadband Radio Service (CBRS), which has become available for use in the U.S.

Ultimately, what utilities need are broadband connections that can reach anywhere and everywhere and support the rapid growth of machine-to-machine communications and the dramatic increases in field devices of all kinds (sensors, IEDs and more) that characterize the IoT. This will provide the required communications foundation for greater automation and transformation to new business models. Utilities need networks that will expand and adapt to meet their needs as the demands of the market shift and evolve, offering a path to a future that is almost within reach.