Utilities face challenges to running their grid operations efficiently and cost-effectively. Private LTE broadband networks provide mission-critical monitoring and control capabilities that previously were not available.
Utility field area networks typically monitor and manage power transmission and distribution facilities over wide areas with narrowband supervisory control and data acquisition (SCADA) and advanced metering infrastructure (AMI) systems. Narrowband, unlicensed frequencies offer connection speeds only in the Kbps range.
Today, utilities’ challenges are complex. Private LTE systems deliver broadband connections that address that complexity.
Note that private LTE involves several key aspects: dedicated spectrum, dedicated network (RAN & CORE), and dedicated devices (custom or programmed).
Distribution automation involves multiple intelligent devices at substations where data streams now range around 3 Mbps and are expected to double or even triple that capacity in future. At the grid edge, new smart city applications include monitoring of streetlights and AMI data collection points.
Another challenge is integrating and managing in real time, power generated from distributed energy resources such as wind and solar systems that may be independently owned and operated. Certainly, balancing supply with peak demands for energy consumption among residences and businesses is ongoing.
Threats posed by severe natural disasters – wildfires, hurricanes, superstorms – cannot be underestimated. Private LTE supports large numbers of fault sensors across the grid allowing utilities to monitor and assess in real-time the impact of power outages. By knowing fault locations, operations personnel or automated devices can isolate those faults and reroute power, thereby minimizing the outage impact on customers and facilitating faster restoration.
Cyber-attacks are a constant worry. With private LTE, a utility can control where to deploy communications infrastructure, how much coverage and capacity is needed, and which applications require priority access.
Utility SCADA, AMI and LMR systems typically operate in the 900 MHz ISM band for narrowband data and voice communications. By contrast, private LTE networks provide broadband capacity and low latency necessary for near real-time high-speed data access in use cases such as dynamic Volt/Var optimization.
Utilities’ interest in private LTE use has grown with availability of new licensed low- and mid-band spectrum for wide area capacity and coverage.
A transitional 2 MHz of paired spectrum in the Upper 700 MHz A Block is available for NB-IoT, SCADA, DA or numerous narrowband LTE voice and data applications. More than a dozen electric utilities around the country have licensed this band.
In May, the FCC approved the use of utility-grade broadband over licensed 900 MHz spectrum. A 6 MHz (paired 3 MHz blocks) portion of the 900 MHz’s 10 MHz channels was granted for broadband LTE use with the 4 MHz balance sustained for ongoing narrowband operations. Woodland Park, NJ-based Anterix holds the largest portion of that licensed 900 MHz spectrum.
Ameren, the big Midwestern utility with 2.4 million electric customers in a 64,000 square mile operating area across Missouri and Illinois, was one of the first utilities to license Anterix’s 900 MHz spectrum for LTE. Ameren consolidated multiple communications and data acquisition systems onto the Nokia-supplied LTE platform and is realizing grid management efficiencies.
Using licensed 900 MHz spectrum offers advantages. With unlicensed 900 MHz LMR networks already in service, utilities can repurpose existing towers and backhaul facilities with less capital expenditure to design, install and harden private LTE infrastructure for wide area operation.
The recent upper mid-band 3.5 GHz CBRS auction made available more spectrum for private LTE use. The auction included 11 utilities, both IOUs and rural coops alike, as qualified bidders. Except for Exelon that did not bid, 10 utilities won 371 PALs in 150 counties for $174.2 million.
Three companies stood out. Alabama Power Company was the volume winner paying $18.9 million for 271 licenses in 103 counties in Alabama and Georgia. APC serves 1.4 million customers over its 44,500 sq mi service territory.
San Diego Gas & Electric spent $21.3 million for three PALs in two counties covering 3.6 million customers in San Diego County and south Orange County, its 4,100 sq mi operating area.
Southern California Edison doled out nearly $119 million for 20 PALs in its 15-county 5,000 sq mi operating area covering 15 million customers.
Note that these utilities paid an average of $0.36 per MHz-POP compared to $0.21 for the overall auction. APC was below average at $0.14 while San Diego G&E paid the highest at $0.57 followed by SoCalEd at $0.51, showing the relative value differences in each market.
The 3.5 GHz 10 MHz PALs are well-suited for high-speed, low latency data connections in both dense urban and rural areas.
by John Celentano, Inside Towers Business Editor