Electric Utility Industry Is Constantly Evolving
Within the electric utility industry, concerns over outage costs, distribution and transmission loss, and cybersecurity threats are leading to an increased focus on more flexible distribution substation topologies and the integration of renewable energy sources, while also increasing the penetration of intelligent sensors and controllers in the grid.
As renewable energy and distributed energy resources become more commonplace, they’re impacting both the size and complexity of the networks, with new substations being added and microgrids becoming more prevalent. Additionally, sensors and re-closers with built-in communications enable faster fault location isolation and service restoration (FLISR), which in turn minimizes outage costs, while smart meters and AMI provide better analytics on managing demand variation.
There are also increases in data capacity requirements, so that field engineers can access back-office resources at the substation and field network level and robust security systems – including video surveillance – to provide both employee and asset security.
Finally, while the majority of the electric utility concerns are centered around providing increased efficiency and availability to their existing customers, it’s also important to note that there are 1.3 billion people around the world who still do not have reliable access to electricity, and these improvements make extending the grid with low-cost, efficient solutions a real possibility.
PLTE Applications for Electric Utilities
In this article, we’ll example various applications for wireless connectivity in electric utility automation while also considering the benefits of a private wireless network as compared to alternatives, such as wireline networks.
SCADA Networks
Typically, for utility infrastructure, sensor data collection is facilitated by supervisory control and data acquisition (SCADA) solutions, with sensors and data sources spread over a large geographic area.
As network devices are becoming more intelligent, SCADA systems are being used not only for control and monitoring but to provide end-to-end analytics. However, this shift means that security requirements are increasing, which are in turn further increasing the size of the packets needed to carry the traffic.
Wireless broadband solutions can handle the increased load, aggregate the SCADA data, and transmit it over relatively long distances with low latency back to the centralized SCADA masters and network operations centers.
Network Resilience and Recovery
As more electric utilities begin deploying wireline technologies – such as fiber and copper – for their mission-critical communication networks. The more they come to rely on these networks, the more costly an outage becomes in the event of a natural disaster or man-made attack.
A utility’s ability to continue – or quickly resume – operations during a time of crisis and ensure the protection of its customers can differentiate it from its competitors. Wireless broadband, whether deployed as an always-on, real-time backup solution or as a rapidly deployable response system, is a natural fit for disaster recovery because it can be counted on as the fastest way to restore communications.
Remote Connectivity to the Home Office
Today’s utility systems are far more complex than they used to be – and growing every day. The information needed for troubleshooting, planning, and installations requires field engineers, now more than ever, need to have connectivity back to the home office, as well as to the Internet.
Field engineers are now able to use their smartphones, laptops, and tablets to connect to secure, industrial grade Wi-Fi hotspots and login to their corporate infrastructure, powered by wireless broadband in areas not covered by the public 3G/4G networks or reachable by fiber.
Video Surveillance and Security at Each of Electric Utility Substations
Private wireless broadband solutions are a fantastic option for providing connectivity to security and surveillance equipment.
Not only does it allow cameras and connected equipment to be located where they’re needed – rather than where a wired connection can reach – but wireless backhaul can also deliver the bandwidth required for both local storage and on-demand access or constant streaming. Now, license plate readers and facial recognition applications can provide confirmation of who’s on-site, while thermal imaging cameras can provide constant monitoring of outage and overload conditions, all without the recurring expense of bandwidth consumption.
Leased-Line Replacement
By migrating to a PLTE solution, electric utilities are able to avoid the recurring monthly operating costs that come with leased wireline networks from telecommunications companies. They can also improve efficiencies by avoiding the limited capacity of leased lines, and the long waits to increase said capacity.
Finally, many telecommunications companies are phasing out low-capacity analog lines, which means electric utility companies must find a suitable alternative to the more expensive – but not conducive to utility operations – digital circuits.
Why Private Wireless Networks Are Best Suited for Electric Utility Automation
There are, essentially, three options for electric utility companies when selecting a communications infrastructure:
- private or leased wireline networks,
- public wireless networks, such as the 3G/4G mobile infrastructure, or
- private wireless networks.
In most cases, the best answer is a combination of these, but here are some reasons why a private wireless network delivers the best overall total cost of ownership.
Quick Deployment
Private wireless networks can be quickly deployed and placed in the exact location where the data is needed. There are no major, months-long construction initiatives, such as digging trenches and running cables, that need to be undertaken. This lack of trenching, cables, and hardwired infrastructure helps lower maintenance and operational costs.
Flexibility and Reusability
Wireless networks are able to cover wide geographical areas, providing flexibility both in remote node placement and reusability of the infrastructure.
Prioritizing Traffic and Applications
By using quality of service, the utility can prioritize its most important data while leveraging capacity for different applications. The existing public 3G/4G mobile networks have no means of prioritizing mission-critical traffic for utility companies or even ensuring the utilities have the capacity they need.
Low Recurring Costs
Private wireless networks have low recurring costs. There’s no need to provision field engineers with 3G/4G data access or lease lines from telecommunications carriers.
Key Considerations in Choosing a Technology for Private Wireless Networks
There are a variety of networking technologies being deployed by electric utilities, each with different capabilities. Here are some key considerations when discussing these different techniques.
Topologies (PTP, PMP, Rings, Mesh)
For networks requiring a lot of capacity over a long distance or for short-range spurs connecting a single location to the wireline backbone, Point-to-Point (PTP) topologies are the best option. PTP connections use narrow antenna patterns that are less susceptible to interference, therefore enabling them to cover longer distances. PTP links can acquire resiliency by deploying parallel sets of radios in 1+1 or 2+0 configurations.
Typically deployed to cover sectors or cells, Point-to-Multipoint (PMP) networks provide scale and capacity over a geographic area. The ability to scale both in the number of nodes per cell and the ability to place cells next to each other without interfering is a key capability for PMP networks.
Ring topologies are excellent for resilient operations of high-capacity links covering a large area.
Mesh networks can be built using multiple PTP links or specialized meshing protocols to enable multiple paths from point A to point B. However, they have the downside of each packet traversing multiple hops, which can lead to lower capacity given the infrastructure investment.
MCA’s premier radio offering, powered by Motorola Solutions MOTOTRBO, have the capability to ensure that adjacent PMP radios do not interfere with each other.
Capacity vs. Range
Several factors – including spectrum, transmitter power, channel bandwidth, noise immunity, terrain, and antenna size – impact the amount of data capacity that can be delivered at a particular distance (or range).
Typically, the farther the range to be covered, the lower the capacity. Low-frequency, narrow-band channels with a high-gain antenna will typically provide the longest propagation, while wider channels will provide a higher capacity.
Licensed vs. Unlicensed
Wireless spectrum can be characterized as either licensed or unlicensed. Organizations can purchase access to a specific channel in a specific location, acquiring what is known as a licensed spectrum.
When using this channel, the organization should encounter virtually no interference. However, the spectrum may be expensive to access and/or extremely scarce. Additionally, it can be a lengthy process to obtain the proper approvals, so licensed spectrums are not ideal for rapid deployment.
Unlicensed spectrum is – as its name suggests – unlicensed by anyone and, therefore, generally open and available to anybody to use. The tradeoff is that competing systems may occupy the same channel at different power levels leading to interference.
Line of Sight vs. Non-Line of Sight
There are two primary types of radio links – line of sight, where there is a visual/optical path between two radios that make up the link, and non-line of sight, when there is an obstruction between the two radios.
Generally, lower-frequency solutions have better propagation than higher frequencies. Wireless solutions above 6 GHz wireless solutions require line of sight links. From 1 GHz to 6 GHz, the capabilities will vary, and below 1 GHz the propagation becomes much better.
MCA, powered by Motorola, offers a variety of solutions in 5 GHz radios that will maximize the propagation of signals, including multipath, OFDM, ARQ, and radios designed specifically to work at low sensitivities.
Security
Now, more than ever, wireless communication security is of the utmost importance to electric utilities. Ongoing cybersecurity threats are a constant concern, but there are a few things that utility companies can look for in their solutions to protect their infrastructure and data, including:
- Encryption for the over-the-air link
- Secure management interfaces with HTTPS and SNMPv3
- Multiple user accounts with password complexity rules
In order to provide users with the best security solutions possible, MCA offers solutions validated to FIPS 140-2, a US Federal government security standard with FIPS compliant avigilon cameras and Cradlepoint routers.
Quality of Service
In order to make the most efficient use of the available spectrum, operators can deploy multiple services on the same channel to ensure the most important information is transmitted with the highest priority.
By utilizing a solution with multiple Quality of Service (QoS) levels that can sort traffic based on layer two and layer three standard classifiers, data can mark the priority or class of service, and the network will ensure traffic is delivered with the appropriate level of urgency and criticality.
Network Management
In order to minimize the effort of the network and reduce unplanned outages, and, in turn, reduce events that may have a negative impact on the total cost of ownership, systems should allow centralized management of the configuration, performance and trend monitoring, fault detection, and security validation.
MCA offers a wide range of radios to fit your needs, including those that support web-based interfaces and centralized management systems.