Utility Professionals Discuss Digital Migration Issues During Roundtable
May 14, 2012
As the utility industry moves toward the smart grid, mobile radio communications and digital technologies will become even more important because of reliability, spectrum and backup needs, said utility professionals during a roundtable May 3. Mission-critical communications issues, including coverage, data, spectrum, security and others, were addressed during the discussion.
Although commercial networks are used for some applications — meter reading and satellite services, for example — communications managers prefer private networks that give them more control.
Rappahannock Electric Cooperative in Virginia was operating its meter reading system on a commercial cellular network, but used a grant to upgrade its private system, said Dennis Buchanan, telecommunications technician. “With DOE (Department of Energy) money, we will replace [the commercial services] with our own network. If it's a problem, it's our own problem, and we don’t have to rely on anyone else to fix it,” Buchanan said.
“We have outsourced copper for SCADA (supervisory control and data acquisition) and satellite for years,” said Doug Houseman, vice president technical innovation for EnerNex. “Utilities have to make sure they have SLAs (service-level agreements) for all those things they can't control.”
Control is essential for utilities following a disaster. “Reducing the network [access] during emergencies is important. Utilities must restrict access to those who can help recover or restore,” said Klaus Bender, senior director of engineering and standards for the Utilities Telecom Council (UTC).
“I would want to constrain my system so the radio system doesn't co-mingle with other systems,” said Robert Ward, program manager for narrowband compliance for PacifiCorp, which serves customers in six states.
Redundancy becomes more difficult in an IP environment, said some roundtable participants. If the telecommunications system is IP and the radio network has an IP core, utility professionals question whether the radio system will go down if the main system goes down. System design is the key to reliability in most instances, said the participants.
However, keeping a network redundant and separate over time isn’t easy, said participants. “You can build a two-way radio system that is completely different than the corporate network,” said Kelly McNair, manager telecom strategy for Oncor, a utility in Texas. “But with two routers in a closet, some guy might converge them into one, and then it's a problem.”
“Utilities don't have spectrum,” said Kathy Nelson, principal telecommunications engineer for Great River Energy in Minnesota. “Our networks are designed the way they are because we don't have spectrum.”
One benefit of digital technology, including Digital Mobile Radio (DMR), is the possibility of adding more data applications using currently available spectrum.
“With DMR, you have much better control of data and channels,” said Bob Fay, chief technology officer (CTO) of Applied Communications. “The existing infrastructure is very chatty. So middleware is a way to address that. Code writers need to understand the medium they have to work with. Application writers need to write with less bandwidth.”
Rationing a DMR network’s applications to only those that are mission critical could help solve the bandwidth problems, said the professionals.
“If you forget about trying to do high-bandwidth applications over DMR, there are some fleet applications that make the radio more like a regular phone,” said Rick Dobbe, principal communications engineer for Black Hill Power in South Dakota. “You could justify DMR by taking away the cell-phone costs.”
UTC’s Bender cautioned utilities from using AVL applications without a dedicated channel. “It disables the channel for other uses,” he said. “It's a shared channel, and you have interference.” For more on interference issues at VHF frequencies, see “PSCC to Certify TDMA Only for Voice Following Interference Reports.” (link to http://www.mccmag.com/newsArticle.cfm?news_id=8253)
Utilities generally design their networks for mobile coverage because portable coverage is too expensive. The propagation of DMR depends on the area and frequency, antennas, vegetation and other factors, Fay said.
Executives said vehicular repeaters could further extend coverage. “You still need mobile to mobile when base stations go down,” UTC’s Bender said.
In Brazil, the regulatory environment has forced many users to digital technology. Brazilian telecom regulator Anatel mandated narrowbanding to 12.5 kilohertz channels similar to the U.S. narrowbanding deadline. Also, vendors can’t type approve analog products so they must use digital, said Kazimierz Malachowski, commercial director for system integrator SGM Telecom. “Coverage isn't as good in remote areas in Brazil,” he said. “Utilities receive governmental fines if something goes wrong.”
“Securing the information going over the network but also the features is important,” said Jonathan Pollett, principal consultant at Red Tiger Security. “Things on the wired side might not always be secure on the wireless side. Each piece of the chain must support all the cybersecurity requirements along the way.”
Utility professionals all agreed that knowledge of radio technology is declining with fewer people understanding RF technology.
“We didn't bring in all the IT people, but we brought in networking people to work with RF people,” said Vernan Hogge, communications director for Northwestern Energy, which services customers in Montana, Nebraska and South Dakota. “We're being forced into it. RF can't ignore Ethernet and routing anymore.”
As radio technology moves to digital protocols, staff experience becomes even more important. “There might be a short supply of qualified guys to work on these networks,” said Ron Bilodeau, project manager demand response for NV Energy in Nevada. “All the qualified technicians go to more sexy technologies.”
Tait Communications sponsored the roundtable. MissionCritical Communications was the official media partner.