In 2006, the Federal Highway Administration reviewed what went wrong for transportation agencies during the August 2003 Northeast blackout. Its guidance since then has been consistent: back up the equipment that actually needs it, not just the equipment that’s easiest to reach. Evoltix builds the Zero-Glitch Power Module, or ZPM, a power intelligence system built around exactly that gap.
Source: Federal Highway Administration, Effects of Catastrophic Events on Transportation System Management and Operations, FHWA-HOP-08-015 (2006).
Two decades after that FHWA review, a lot of state DOT communications tower power still traces back to a UPS that was specified before half the equipment on that tower existed. The ZPM is not a UPS. It is what state DOT communications teams install when a UPS is no longer enough to carry a tower site through the events that actually test it.
This isn’t a story about one bad blackout. It’s about what happens when a communications tower’s job quietly grows for fifteen years while its backup power stays the same, and about the gap that opens up between what a UPS was specified to carry and what the tower is actually carrying today.
A Tower Network That Answers to More Than One Agency
A state DOT’s radio tower footprint rarely serves the DOT alone. Minnesota’s ARMER system, for example, runs on a backbone of towers and shelters that MnDOT owns and maintains, sharing capacity with the State Patrol, the Department of Natural Resources, and local public safety agencies statewide.
Source: Minnesota Department of Transportation, Statewide Radio Communications program.
When a DOT-owned tower is running a UPS sized for a smaller job than the one it’s actually doing, the outage doesn’t stay inside the DOT. It shows up on every agency riding that same backbone.
What an Aging UPS Actually Costs During a Storm
Picture an ice storm knocking out utility power along a rural interstate corridor. The traffic management center loses its camera feeds and its message signs right when it needs them most. Maintenance dispatch loses radio coverage to the plow crews working that same corridor. None of that happens because the grid failed. It happens because whatever was supposed to carry the site through that failure was sized for a bridge, not a storm.
A traditional UPS battery backup, the kind installed under a service contract a decade ago, is built to hold a load for five to fifteen minutes: long enough for a generator to catch, assuming the generator starts and a fuel truck can reach a site the storm just cut off. The ZPM’s battery-first architecture is built to carry the load through the storm itself. At a 2 kW critical load, a typical draw for a DOT communications rack, the ZPM 1 delivers 3.84 hours of rated runtime. At 1 kW, 7.68 hours.
A UPS sized for a five-minute bridge and a system built to survive a six-hour storm are not the same purchase, even when they’re both called backup power.
What Changes When the Tower Site Gets Modernized, Not Replaced
Field service still makes the initial connection to a site’s grid and load, since every DOT tower cabinet is wired a little differently after years of equipment added on top of equipment. Past that first connection, there’s no on-site battery bank to assemble and no separate inverter to size and install. The ZPM is a rack-mounted unit, 850 lbs fully configured, built for the standard 19-inch equipment enclosures most tower sites already use.
Battery chemistry is where a lot of the ten-year cost sits. LFP batteries are rated for up to 15 years, against the 3-5 year replacement cycle on the lead-acid batteries most legacy UPS systems still run, which matters more the longer an agency expects to hold onto a capital purchase.
IntelliCore, the software layer running on every ZPM, gives a network team real-time visibility into battery state of charge and grid status from a single dashboard, plus up to 26 mappable dry contacts for alarms that plug into the alerting a network team already uses. That’s advanced diagnostics and trending data an agency can act on, not a quarterly inspection report that only says what already happened.
Scale tends to follow trust here, not the other way around. A government buyer defending a capital line item usually starts with a single pilot site, not a network-wide rollout, and wants to see field results hold up over a full budget cycle before asking for more. That’s a slower path than a single splashy number, but it’s the one that actually survives a budget hearing.
Planning a DOT Emergency Tower Power Upgrade
Most state DOT networks don’t need to modernize every tower site in the same budget cycle. Start with the sites where the UPS is closest to end of life, the sites carrying shared interoperability traffic for other agencies, and the corridors where a storm-season outage would also cut off road access for a service truck. That’s usually a short list, and it’s the list a capital budget request can actually be built around.
Talk to an Evoltix application specialist about your tower network’s load profile and backup risk, or start with a no-cost look at the numbers in a Total Cost of Ownership Studio session.
Contact: evoltixenergy.com/contact/ Call: +1 (855) 964-9274
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