In the race to the smart grid, wireless will power grid modernization

Sustaining a constant flow of power is complex and challenging. Utilities must not only deliver on this primary responsibility, but also address expanded pressures. Power generation is evolving to prioritize sustainable resources. With the popularity of solar panels, consumers are producing as well as consuming energy. Economic forces, security threats and natural disasters add further pressure on utilities. To meet these challenges, utilities are undergoing digital transformation. Let’s unpack the components of the digital power grid modernization and see how wireless private networks are enabling utilities to achieve their goals at every step of the journey.

Optimizing the world’s most complex machine

Some call the power grid the world’s most complex machine. Power grid infrastructure management must balance power generation with power consumption because grid instability can lead to blackouts. Previously, only consumption varied. Today, with the growth of sustainable resources such as solar and wind, there’s now variability in power generation as well as consumption. Ensuring that the power inserted into the grid is always balanced with the consumption from the grid takes a delicate choreography. To survive, utilities must adopt digital solutions. This is where private networks make their mark. Network evolution to cellular brings utilities the advantages of a large and rapidly developing ecosystem of global sensors and devices. And security, reliability, and independence in the design of wireless network quality is especially valuable to utilities.

The journey from power plant to your home

To set the stage for the role of wireless in power grid modernization, let’s first get a simplified view of the major functional aspects to the power grid (Figure 1).

Figure 1: The power grid

Each component of the grid must communicate with the others, a task that has grown more critical as utilities progress in modernizing their power grids.

Interconnecting generation and distribution at the substation

Transmission substations control the input of power from the power plant into the distribution grid. They can be located in remote areas, far away from the control centers. Long-haul wireless provides connectivity between the transmission substation and the established wide area network that monitors the power grid. Wireless technologies like long-haul microwaves, can be used instead of expensive fiber upgrades or low-speed links, adding improved latency and performance.

Distribution substations ensure continuity and reliability of power towards industrial, commercial and residential consumption by switching in power sources based on demand and fault detection/isolation. They’re usually closer to population centers and, therefore, to the consumption. A private LTE network enhances or expands existing data connections and offerings. Wireless networks also add a layer of reliability to the operational communication needed to monitor and control the substation. Many of these devices are already reliant on a backup public wireless network, that could now be replaced by a better-designed, predictive private wireless network.

Wireless networks—for grid management and use case convergence

Power grid modernization includes use cases such as smart video monitoring, that requires a ramp-up in performance characteristics—best provided by an advanced wireless network. The same private wireless system that offers superior performance also lets utilities integrate employee devices with private enterprise features. As the sensors and substation Intelligent Electronic Devices (IEDs), remote terminal units (RTUs) and relay systems migrate towards wireless, grid management and corporate communication will also be integrated into the same mobile devices. With the IT and OT worlds brought closer together, utilities will see a significant decrease in operational complexity.

Teleprotection is also enhanced by wireless networks. Teleprotection monitors the condition of the grid, isolating faults and preventing damage to critical parts of the power grid. Rapid response is critical. The right combination of wireless 4G/5G low-latency solutions, can extend the reach of teleprotection beyond the local substation to more central locations. The use of Artificial Intelligence/Machine Learning (AI/ML) will allow for proactive fault isolation. The development of the device ecosystem for wireless technologies like 5G NR will open further advances such as remote control of mission-critical switching infrastructure.

Eliminating the copper wire

Substations today have copper-driven dedicated lines to each primary control element, running a single use case at a time. To expand the substation’s capabilities, a utility would have to add wiring and upgrade cable trenches that connect the switchyard to the control room. In addition to being unwieldy, these systems are analog. Transformation of the substation starts with upgrading the communication infrastructure from analog to digital and upgrading the transport between switchyard and control room to the right combination of fiber and wireless. With wireless power grid modernization in place, we can collect more, and more granular data continually and proactively manage disruptions.

In the control room, indoor wireless LTE, combined with mid-band spectrum like Citizens Broadband Radio Service Priority Access License (CBRS PAL), provides higher throughput for video monitoring, high chatter and high throughput traffic. Indoor wireless LTE can integrate seamlessly with the outdoor macro-LTE network. Employee communication within the control room can even be integrated with the power grid’s network.

Bringing power grid security, convenience and convergence to the last mile

As utilities continue to adopt power grid modernization, the reliability and security introduced by LTE wireless will extend from power distribution to the last mile of the power delivery infrastructure. The last mile is where power enters the consumer domain. It’s also where safety and security become paramount.

Many environmentally aware and cost-conscious consumers invest in solar panels for their homes. Consumers can now potentially send energy back into the grid and track it in near real-time. What was once traditionally unidirectional is now bidirectional, with customers returning power to the grid while consuming power from the grid. The new reality of “producing-consumers,” or “prosumers”, requires real-time feedback to ensure that the utility can successfully balance generation and demand.

New to the neighborhood—real-time monitoring

LTE wireless offers a new advantage to grid management at the last mile: real-time data. Real-time feedback from LTE wireless in the last mile enables utilities to ensure power grid security and be more proactive in staying ahead of potential faults in the neighborhood grid:

• Substations receive information needed to isolate smaller parts of the neighborhood grid, avoiding instability and blackouts in the larger grid.
• Safety is enhanced by proactive monitoring of weather-stricken infrastructure.
• A real-time analysis of consumption and prosumer generation allows for more efficient onboarding of distribution energy resources across transmission and distribution substations in the power grid.

Ensuring adequate bandwidth in the last mile

The last mile is also where consumer traffic from smartphones and fixed wireless competes with utilities traffic to power grid devices. Because demand on internet access is at its maximum here, running critical devices for the power grid on the consumer smartphone network can be both unreliable and expensive. A dedicated Private LTE network for the power grid ensures that reliability on the power grid is not impacted when capacity taken away by competing consumer devices.

As families migrate to suburban neighborhoods, utilities are racing to expand existing last miles of power infrastructure. The time-to-activation of internet connections for new power grid devices on the suburban grid is quickest with wireless and is most reliable with licensed LTE wireless.

Private LTE network for a secure, reliable last mile

Prosumers, with their solar panels, are just one facet of the complex shift in the operating landscape for power utilities. Utilities are asking: How do we maintain that delicate two-way conversation between production and consumption in a prosumer world? How can we quickly and cost-effectively extend our infrastructure to serve new customers and better serve our current ones? And when we open up our grid to prosumers, how do we ensure the security of our mission-critical grid?

As we’ve seen, LTE wireless enables new technologies and improved efficiencies that answer many of the challenges facing utilities. As utilities continue to adopt power grid modernization, the reliability and security introduced by LTE wireless will extend from power distribution to power delivery infrastructure.

Connectivity at the last hop: the Converged Cellular Capillary Network

Now we get to the last hop in the last mile—where all sorts of multipurpose, non-3GPP devices such as smart meters await. In the emerging smart grid, more applications also promise more devices to manage. Today’s two-way reporting on power generation and consumption will soon sprout local weather reporting, video monitoring and other applications.

The power grid today contains numerous purpose-built capillary networks, each optimized for a single use case. Capillary networks consist of a capillary gateway (CGW) and many devices served by that gateway. Performance, reliability and consolidation call for multipurpose networks in the last hop. The logical next step is to merge these access networks by leveraging the common core infrastructure provided by private LTE through Converged Cellular Capillary Networks.

Connecting a capillary network to the global communication infrastructure can be achieved through a cellular network, which can be a wide-area network or an indoor cellular solution. The gateway between the cellular network and a mesh capillary network acts just like any other user equipment when that gateway is enabled with a SIM.

Wireless connectivity enables the smart grid

As the connected world moves towards a wireless internet world, an increasing number of connectivity options will become available to utilities. Wireless technology opens up new opportunities for expanded control, scale and reliability in interconnecting power generation and distribution. With adoption of the right spectrum, device ecosystem and technology, wireless will also allow for consolidation of mission-critical fault location, isolation and restoration.

As the power industry strives to modernize in response to growing demand and business imperatives, mission-critical wireless networks will play a key role in enabling utilities achieve successful power grid modernization. Ericsson is partnering with utilities, providing solutions that connect every component of their grid, from power generation to that smart meter in your home.

There’s much more to know

This blog gave you an overview of the issues involved in grid modernization, on the challenges utilities face and the solutions that wireless networks provide in building the smart grid. But we’ve only touched the surface here.

Learn more about mission-critical wireless connectivity and the journey to power grid modernization.

Download Ericsson’s paper here.