TETRA is thriving in the utility sector because of its reputation for being extremely reliable for critical voice and data. Laurence Doe investigates the factors driving the market
There is no doubt that TETRA can meet utilities’ needs for wireless communications. Both voice and data are heavily used and features that support situations such as lone working are essential. If TETRA continues to meet utilities’ evolving needs there is little threat of another technology being seen as a better alternative.
“There’s more available and on offer [from TETRA] than some utilities realise,” says Phil Kidner, CEO of the TCCA. “They’re beginning to recognise that. I think that utilities will be customers of TETRA for a long time yet.”
The resilience and robustness that TETRA can provide is sure to drive deployments for some time yet as utilities develop new networks and update their terminals and systems. One example of this is the large-scale national rollout of the TETRA Enhanced Data Service (TEDS) network Nødnett in Norway.
Although primarily meant for use by the emergency services and public safety agencies, utilities are also using Nødnett and embracing its TETRA technology. Every organisation that wants to use Nødnett is required to apply to and be acknowledged by the Directorate for Emergency Communication (DNK).
Norwegian utilities qualify as Nødnett users because of the critical nature of their operations and infrastructure. They are having to upgrade their communications because of backup power regulations, which changed thanks to the new technologies available through Nødnett.
A DNK representative explains that for utilities “[TEDS] will replace old analogue systems for voice services. The data services will be an addition to existing systems, a replacement for old solutions in selected sites, and also a substitution for manual tasks in some areas”.
At the time of writing there were three utilities changing over to Nødnett. Svein Almås, head of operations at Helgelandkraft (a hyrdroelectric power plant serving Helgeland in northern Norway), is preparing for the move.
“We were in the process of acquiring a new radio network and considered different options,” explains Almås. “Nødnett has better coverage than we could possibly build with our own radio network and by choosing it we will also contribute to increasing the robustness of the network.”
The company previously operated an analogue system and Almås hopes for better coverage with TETRA.
“Nødnett has coverage in areas we did not have coverage before. In these locations we previously used mobile phones to communicate. Switching back to our radio network in areas with coverage was done in various degrees. So my hope is that our employees will use Nødnett more as there is no longer the same need for mobile phones and that this will lead to better communication.
“It can be a challenge to get everyone to use a new system,” he adds. “To ease the transition we will have super users that will help implement it in our organisation and also act as support.”
Almås explains that safety is key and Nødnett will allow the control room operator to set up talk groups so that critical information reaches everyone that needs it at the same time.
“Our goal is to use Nødnett to control remote terminal units, in the hope that this will have a positive impact when power outages occur.”
SCADA power
Monitoring and control of a network saves a lot of time when you consider that it could take hours to locate a certain section of a utility grid. This is where supervisory control and data acquisition (SCADA) comes to the rescue. CREOS Luxembourg, the main electricity transmission and distribution operator in Luxembourg, is one example of a utility that’s implementing TETRA and making particularly good use of SCADA. The company utilises SCADA to make the medium voltage grid accessible, and to decrease outage times.
Nick Smye, chair of the TCCA’s SCADA, Smart Grid and Telemetry working group, says that TETRA is a good technology for SCADA because of its encryption. The short data channel is “very fast at typically one to two seconds”.
SCADA is key for utilities in such applications as the remote monitoring of overhead power lines, operation of valves, monitoring liquid levels, flood prevention, and the control of pumping systems. Another important feature is fault passage indicators for lightning strike detection. These show where the break is so the faulty part of the line can be switched out and power restored.
“It’s a relatively small amount of data but you can do an awful lot with that if you’re using intelligence protocol compression,” comments Smye. “You certainly don’t want to try and run a standard line protocol over the air as repeated polling can waste a lot of capacity.”
CREOS Luxembourg is using TETRA infrastructure from Sepura, which will collect basic data from medium voltage substations to gain better visibility of the medium voltage grid. This will also help identify potential problems and decide which medium voltage substations should also feature a remote control capability.
The project will be completed by the end of 2022 and a total of 2,850 remote terminal units will be used to manage the electricity and gas networks, with SCADA ensuring uptime even during power failures.
“Flexible allocation of control channel capacity and packet data also brings benefits such as being able to save the control channel for signalling. And you get voice,” adds Smye. “It’s quite nice in TETRA as you can easily add extra control channel capacity by using some of the traffic channel capacity.”
CLP Power in Hong Kong has been upgrading its TETRA network for more than a decade and recently won an International Critical Communications Award for its work in this area. It provides voice and SCADA capabilities through 19 outdoor sites. This includes nine hilltop locations for wide area coverage, supplemented by seven rooftop sites at power substations and three sites situated within power stations.
It comprises more than 23 TETRA base stations across the entire territory, with each base station equipped with
two to three carriers, depending on the site topology and the user density.
“They were so impressed with SCADA that they built a separate add-on TETRA network purely for SCADA,”
says Smye.
The TCCA SST (SCADA, Smart Grid and Telemetry) working group is a forum for users, manufacturers, system integrators and developers to share experiences and requirements, and catalyse the market for TETRA in the SCADA, telemetry and smart grid space. Its aim is to encourage and support the development of suitable solutions; both for traditional SCADA and telemetry applications and for new application areas such as smart grids.
The group meets by conference call every few months. It maintains a list of current TETRA schemes, and has collected a number of whitepapers and marketing presentations.
- Visit www.tandcca.com/about/page/21902 for more details.
What’s standing in TETRA’s way?
Smye explains that TETRA uptake depends on a firm’s finances, “which are affected by whether a utility wants to build its own infrastructure or buy a service, the size of the operating area, and regulatory constraints”. But he adds that these factors are not influencing many parts of Europe and the Far East as there are a number of utilities using TETRA in these territories.
Additionally, the personnel using the system and their reliance on either voice or data is taken into account.
Legacy systems also influence the decision to deploy TETRA as the utility may have a SCADA system that is already suitable.
TETRA is seen as a viable communications option by utilities in North America and has been endorsed by manufacturers such as the Sepura Group of companies, which includes PowerTrunk and Teltronic. Keith Ammons, VP of market development for PowerTrunk, says that P25 is also considered but the preferred systems are digital. His view is that TETRA’s slow introduction was the result of the technology being “blocked from the market for many years”.
“Most of the utilities are still using a lot of older analogue, VHF and UHF systems,” explains Ammons. “But there are some utilities now that are moving into digital technologies.”
Klaus Bender, principal engineer for SiteSafe – a US RF safety and compliance solution provider – holds a similar view.
“The challenge for TETRA in the United States is still the fact it requires a wide channel and those are hard to come by,” comments Bender. “A lot of those channels are already used in the US, especially in the 450 to 470 [MHz] UHF band, which is kind of a sweet spot for TETRA.”
Ammons says the market share of TETRA in America is “very small at this point” and estimates it to be around one per cent. Although it’s a good candidate and “now starting to take off”, utilities are also considering DMR.
“The handsets and the back-office infrastructure for P25 is the most expensive when you put together the overall requirements for a system,” explains Bender. “But on the lower scale there’s still some DMR technologies that operate on the 12.5 kHz channel and provide a good degree of voice capability. The infrastructure and the terminals sell for much less that TETRA.”
Bender explains that another frequency band where TETRA may make some progress in the US is the 800 MHz band.
“There are frequencies that have been reallocated by the FCC [Federal Communications Commission] and sold at auction. Now some of those are available on the secondary market and we’re seeing utilities go out and purchase spectrum from those that won the auctions to do systems like TETRA.
“Those channels are already 25 kHz and licensed exclusively, so they offer an opportunity for utilities that already have the frequencies who may be seeking to do a system upgrade for a land mobile system. There are utilities using land mobile systems that are still 20-, 25-, 30-years-old.”
Successful US deployments
One North American utility from the small group of new TETRA operators is Ontario Power Generation. Its Pickering Nuclear Generation Site and Darlington Nuclear Generation Site are located close to one another on the north shore of Lake Ontario in Canada. They are part of the Fukushima Emergency Telecommunication Enhancement Project (FETEP) to identify and address vulnerabilities within utility communications.
The nuclear plants’ rollout of PowerTrunk-T base station equipment has almost been completed and will provide wireless communication throughout the sites, including the reactor buildings. Radio coverage will be supported for outdoor and indoor areas in both facilities.
Equipment has been supplied and response times are in the process of being tested with some “tweaking to the configuration” still required, says Ammons. The FETEP project is named after the Fukushima Daiichi nuclear disaster of 2011 and aims to address the most catastrophic of possible scenarios, such as a complete loss of power sustained for four days, or a total loss of coverage both inside the plant and outside with a radius of 40 km.
“All the nuclear power plants wanted to revise their communication requirements, so Ontario Power Generation came up with the project and requested a deployable, rapid response TETRA system to cover both plants,” adds Ammons. The system needs to be able to run for 72 hours on its own power supply.
The company also awarded another contract to PowerTrunk for fixed site communications. This was to replace an older generation of Motorola Solutions’ Integrated Digital Enhanced Network (iDEN), which allowed mobile work crews to communicate over large geographical areas and between campuses through push-to-talk communications.
Ammons adds that US utilities have been experimenting with small-scale SCADA and remote control and monitoring applications over TETRA. TETRA is viewed as being “very well-suited” to SCADA applications such as valve control and non-time-critical monitoring.
But Bender says he is yet to see a utility in the US select TETRA based on its SCADA benefits. “It’s always going to be voice first,” he explains, adding that there are not enough examples of TETRA’s use in the utility sector for its benefits to be fully understood. “They want to be shown either another utility in the US or someone in Europe who has done what they’re trying to do and how they did it, what problems they had and what it looks like now.”
There is, however, room in the market for TETRA to place more footholds. Bender points out some utilities have been using the same land mobile systems on a regular basis for 20 years and these require replacing. But if manufacturers are going to fully embrace selling TETRA in the States they may want to take note of the following advice.
“Vendors located in Europe take longer to give answers, whereas if there’s a US vendor potential end users can pick up and call,” Bender states. “If there’s a local person that’s either in sales or a technical consultant for that radio technology in the area you get answers quickly."
Other TETRA utility installations
- Electricity: Energa, Tauron (both in Poland), Kepco (South Korea), Stromnetz Berlin (Germany), BC Hydro (Canada), Cobb EMC and Demco (both in North America).
- Oil and gas: Sasol (South Africa), Sibur (Russia), Saudi Aramco (Saudi Arabia).
- Water: Bilbao Water (Spain).
