Distribution utilities of all types globally are facing a wide range of new challenges and opportunities brought on by greater customer expectations and enhanced reliability needs. As distributed energy resources (DER) proliferate, new approaches and technologies for managing these new generation resources will add to the complexity of automation approaches at the substation and feeder levels, as well as on low-voltage (LV) transformers at the edge of the grid. Thus, there is a growing need for more intelligence, control, and agility in the distribution grid, particularly at the edge, where many new DER systems are located.
To date, utility automation efforts at the distribution level have been largely focused on issues caused by reliability mandates, outage penalties, customer expectations, electric vehicle (EV) charging, renewables intermittency, shifting loads, capacity constraints, and bi-directional power flows. In the longer term, automation further down in the medium-voltage (MV) and LV network will enable the proactive development of markets for aggregated clean resources and services, service-oriented business models, and end-to-end integrated grid management strategies.
Distribution level automation applications
Distribution automation (DA) and substation automation (SA) technologies and strategies are being adopted to increase the level of monitoring, intelligence, and automation across the distribution grid. These automation solutions can be divided into three major segments:
- Distribution substation automation: A mixed variety of sensors and monitoring devices, mechanical and intelligent electronic devices, switches, reclosers, protective relays, and communications devices, as well as transformers, are found in automated distribution substations.
Substation automation at the distribution level is accelerating, particularly in North America, with many utilities deploying fiber communications to accommodate advanced technologies and software systems. Nonetheless, Navigant estimates that distribution level substation connectivity and automation penetration remains well below 50%, and in the 10% to 20% range – or less – in developing regions.
- Feeder automation: Distribution feeder systems distribute power over cables via either radial feeders or mesh feeder networks running from the substation. Automated feeders are equipped with sensors and monitoring devices, as well as intelligent electronic devices such as fault detectors, reclosers, disconnect switches, fuses, and relays.
To date, feeder monitoring and automation is limited at best, though forward-looking utilities such as Eversource, Florida Power & Light (FPL), Los Angeles Department of Water and Power, Oncor, and others have been deploying sophisticated outage restoration and automation systems.
For example, Eversource’s (formerly NSTAR) 2009–2014 Grid Self-Healing and Efficiency Expansion project involved the deployment of two-way communications infrastructure and DA equipment on 400 circuits in its Massachusetts territory. New switches, sectionalizers, reclosers, and condition monitors were installed to enable automatic detection and isolation of power outages, followed by rapid restoration. The project included LV feeder monitoring in Boston, high-speed fiber optic rings for reliability, monitoring, and control, web-based outage reporting, and a new outage management system.
- Transformer automation: Millions of pole mounted, pad-mounted, and underground LV transformers have rarely been automated in any way. Transformer automation and monitoring include the simple real-time monitoring of voltage, current, power factor (PF), and sometimes oil temperatures and other conditions. This segment may also include more sophisticated automation when connected to a supervisory control and data acquisition (SCADA) system or a distribution management system (DMS).
Distribution utilities of all types are now implementing distribution substation, feeder, and transformer automation technologies and solutions. Navigant Research expects Europe to be the largest regional opportunity over the next several years due to feeder system design characteristics. Currently, the region represents more than half of global DA and SA market revenue.
However, the opportunity is relatively short term and tails off after 2021, when major feeder and transformer automation projects are expected to be completed. In all other regions, distribution substation, feeder, and transformer automation revenue is expected to increase steadily through 2025.
Navigant Research expects global cumulative DA and SA revenue for all technologies to reach $109.1 billion between 2016 and 2025. The annual revenue opportunity is projected to grow from $7.6 billion in 2016 to a peak of $12.5 billion in 2021, and then drop to $12.2 billion in 2025. The overall 2016–2025 compound annual growth rate (CAGR) is expected to be 5.5%. Chart 1.1 shows the growth in annual revenue for the 10-year forecast period by global region.
The key market drivers in North America for increased automation at the distribution level are concentrated around improving reliability, addressing aging infrastructure, changing cost recovery mechanisms, increased visibility into feeder operating parameters, AMI installations, and (to a certain extent) new distribution feeder system and substation construction.
At present, 40–50% of MV substations have some level of automation, and upgrades to more sophisticated control and automation capabilities are being planned.
Feeder automation remains nascent generally, but at FPL in Florida, it became a high priority, as the region is subject to the most lightning strikes in the United States; these storms were a primary cause of faults in FPL’s distribution network. Particularly in remote rural locations and swamps, restoration was time-consuming and costly. In response, FPL elected to complete a system-wide feeder automation improvement project and selected S&C Electric to provide equipment and installation services. The company deployed S&C’s TripSaver II cutout mounted reclosers, which deliver decentralised, intelligent, and autonomous restoration capabilities, across more than 80,000 feeders in its service territory. The project was notable because it covered FPL’s entire network; most feeder automation projects to date are feeder-specific and focus on particularly troublesome segments of the network.
In Europe, the MV substation situation is much different from that in North America. Across many of the countries in Western Europe, the MV substation fleet is 95–100% automated already, though much of the automation may be first generation systems with limited capabilities. Upgrades from early SCADA to more powerful DMSs can be expected to occur.
That said, much T&D system expansion is occurring as Europe’s regional operators reconfigure their networks for large-scale penetrations of DER and large investments in LV transformer substation monitoring and control, as well as feeder monitoring, can be expected. Électricité de France (EDF), for example, is planning LV transformer monitoring and automation across 700,000 or more transformers – the majority of its fleet – by as early as 2020. And Spanish DSO Iberdrola Distribución is implementing its multiyear Network Remote Management and Automation Systems (STAR) project, which has been focused on network remote control and automation in MV substations, as well as on LV transformers and distribution feeders. Once completed in 2018, this $2.2 billion project will monitor and automate approximately 80,000 transformer substations and deploy over 10.3 million smart meters.
Key DA and SA drivers in Asia Pacific include the epic expansion of the T&D system and substations to address both rural electrification and large-scale urban expansion, as well as to replace ageing infrastructure. With a large number of new projects driven by electrification, most if not all new installations will be monitored and (to some extent) automated systems.
The Asia Pacific DA and SA market can be divided into three major territories, each representing approximately one-third of the region’s total market size: China, India, and everywhere else. The DA market in China is led by the country’s Strong and Smart Grid initiatives. Although this market continues to grow, China is notoriously difficult for outside commercial vendors to access, due to price pressure from in-country vendors.
Examples of success in China often include partnerships with Chinese companies. For instance, General Electric (GE) has established a partnership/joint venture with the XD Group, providing local content and presence.
India is experiencing similar price pressures as China, thus giving lower-cost local products and integrators like Tata, Infosys, and Wipro a significant advantage; here too, local partnerships are essential. However, India has fewer centralised protectionist politics compared to China, which has made it easier for international vendors to compete.
The third Asia Pacific segment, Southeast Asia, Australia, and New Zealand, is still widely accessible. Australia and New Zealand were early adopters in terms of smart grid technology deployments. However, local economies have been weak in recent years, dampening demand. That said, Australia has become a major market for distributed solar; rapidly increasing penetration of variable renewables supplies in Australia will force distribution network upgrades.
The days of a largely electro-mechanical distribution system maintained by crews in trucks are giving way to a highly connected, automated, ‘smart’ grid. Connectivity options are increasingly attractive and necessary to support sophisticated software and analytics solutions which improve grid reliability, operational efficiency and flexibility. Especially as the traditional ratepayer, cost-plus business model is replaced by a system more focused on efficiency and services, distribution utilities will find themselves increasingly dependent upon automation solutions to meet the needs and demands of customers and regulators. As such, investment in these technologies is expected to grow throughout the coming decade. MI
ABOUT THE AUTHOR
Richelle Elberg is a principal research analyst contributing to Navigant Research’s Utility Transformations program and heading up the Smart Grid research services, including Connected Grid, Digital Grid, and Dynamic Grid. Her primary focus is on communications networks for utility applications, including AMI and substation and distribution automation applications.
Elberg has more than 20 years of experience in the telecommunications industry, including an extensive background analysing and writing on the wired and wireless communications industries from operational, financial, strategic, technical, and regulatory perspectives.
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