Like many utilities in the U.S., Portland General Electric (PGE) is committed to delivering the majority (80%) of its electricity carbon-free by 2030. At the same time, electricity demand is spiking, and the incorporation of renewables into the grid through Virtual Power Plants (VPPs) is still in its infancy.
Managing these competing goals of increased demand, expanded Distributed Energy Resources (DERs), and reliable power means utilities must access, maintain and control many new grid devices, networks, and data. Additionally, orchestration of “on-demand” DERs working together as a VPP requires a new level of operational insight throughout the grid, from its first to its last mile. In this new world, wireless technologies are a must.
Historically, utilities have relied on a variety of separate networks such as public cellular, fiber and proprietary wireless networks to connect field assets (e.g., meters to energy storage systems, reclosers, and sensors) to monitor and manage the grid. However, options like fiber are expensive, and public cellular has lacked the Quality of Service (QoS), and privacy utilities require in their communications systems. Proprietary wireless networks have worked well, but they often do not scale well, are expensive, and have lacked standardization (and therefore risked obsolescence).
Recently, private LTE (pLTE) became available for utilities to build a more secure cellular option that meets stringent QoS and cybersecurity standards. Still, it requires costly radio/tower infrastructure and leased spectrum. From a deployment perspective, pLTE can take a decade (or more) to roll out, and the utility must maintain it.
Private Mobile Networks (PMNs), a newer cellular option coming to market, promises the privacy of pLTE but is a software-based approach eschewing the need for tower infrastructure. After installing PMN software behind the utility’s firewall, utilities can ride over the existing carrier/operator radio with full control over data path and devices (e.g., quarantining the device in a cyber emergency).
In its early needs assessment, PGE analyzed that the costs of building a pLTE network would total almost $500 million in CAPEX investment. Worse yet, the physical network would take ten years to build, and the cumulative OPEX over twenty years totaled another potential $500 million. PGE did not have ten years to wait and preferred investing the capital to increase generation capabilities.
This article outlines the promise of a new software-based PMNs approach that PGE explored and included lab testing results to share a reference architecture for other utilities seeking a similar solution. Â
The Connected Utility Lab: Testing the Limits of Private Mobile Networking
Could PMNs be trusted? To answer that and related questions about scalability, cybersecurity, and possible obsolescence, the PGE Connected Utility program brought industry thought leaders like Intel, Google, and T-Mobile together with startups like Expeto and 5G incubators like the 5G Open Innovation Lab (5G OIL). It used an innovation ecosystem model introduced and managed by InnovationForce (see Figure 1).
Figure 1: The Mission of the Connected Utility 5G innovation program
The lab created a five-step process to quickly test PMNs and explore solutions to use case challenges (Figure 2). PGE and the solution provider then developed methods to test the tech in the field in 90 days or less. Field trials and “day-in-the-life” results were gathered to determine whether the new solution worked better than the previous one. These metrics were used to assess the business case for the solution. Every quarter, go/no-go decisions were made when better solutions were identified.
Figure 2: Five Step Rapid Innovation Process to Test 5G Use Cases
After strenuous testing in the Connected Utility lab, PGE saw advantages to PMNs as follows:
- Ease of deployment: The software-based, cloud-native solution allows quick, easy, and affordable installation and deployment by the utility’s IT department behind its firewall, running inside its AWS Virtual Private Cloud (VPC) datacenter.
- Standards-based: The ability to offer any flavor of the cellular network from 3G, 4G, 5G and beyond. PMNs are based on the 3GPP international standard, so networks are more forward/backward compatible than proprietary solutions.
- Time and cost savings: Instead of spending millions to deploy and maintain the infrastructure and become an operator of wireless networks, PGE averts this cost and invests it into its core business.
A PMN Reference Architecture for Utilities
Figure 3 shows the typical utility leveraging public carrier networks where devices and data are outside the utility’s control. Data transverses across a public carrier’s network with little security and ability to control data or devices. Network changes require changes to the public carrier network, which may not meet the QoS a utility could need in a storm or wildfire event as the utility may not be given priority access across networks.
Figure 4 shows the ideal future state where the utility controls its own wireless networks, whether public, private, leased spectrum, or satellite. In this scenario, all networks and data would be controlled under one pane of glass inside their control. This could be achieved by installing PMN management software inside a data center that controls utility-owned SIMs embedded inside grid devices that determine the network, QoS, level of security, and data path. The desired requirement is that these networks could be managed by utility IT staff as if they were a logical extension of the security and corporate network policies.
Figure 3: A Typical Utility Current State Using Public Wireless Network Infrastructure
Figure 4: Desired Future State Using Any Wireless Network Controlled by the Utility Under One Pane of Glass
The Desired PMN Solution: The Expeto NeXtworking Platform
After rigorous testing in the Connected Utility lab, PGE selected the Expeto NeXtworking platform for its software-defined approach to creating standards-based and cloud-native hybrid PMNs. Figure 5 shows the end-to-end components of the hybrid PMN deployed and tested at the PGE Connected Utility lab.
Figure 5: The Expeto Hybrid Private Mobile Network Solution for Utilities
Lab tests demonstrate that this reference architecture supports the rapid deployment of significant initiatives for PGE and was valued for the following capabilities:
- Hybrid capability: The Expeto solution allows PGE to create one PMN but choose its preferred network (e.g., 5G, public, private, pLTE, satellite) and manage it as one integrated, hybrid wireless network.
- Control: The solution allows PGE to have its own SIMs to support this network, and profiles can be set up by the need of the device and application. Security policies can be automatically pushed to devices, and data is controlled from the SIM to its termination point. Devices can be automatically quarantined.
Conclusion
With the rush to modernize the grid to meet decarbonization mandates and scale connectivity to a tenfold increase in the number of grid devices being added in the field, at the substation and behind the meter, utilities must think differently about how they connect and secure their networks relying more on wireless and cellular technologies. PGE turned to a software-based hybrid PMN solution from Expeto to accelerate its plan to connect tenfold more devices into its network by 2030. Now, the utility can control any wireless device on their preferred network of choice (e.g., 5G, public, private, pLTE, satellite, etc.) through one secured pane of glass. The PGE 5G Connected Utility Lab continues to test devices in the field in rapid 90-day sprints.