It’s safe to say that the electrical systems supervisor is not the person that Superdome officials wanted the world’s media to be talking about the morning after the Super Bowl. For 34 dimly lit minutes, starting early in the third quarter, that person’s competence was one of the many things that the more than 1 billion people watching the game were discussing.
There’s a lot we don’t know about exactly what happened when the lights went out on the Super Bowl. But here’s what we do know:
Not all the lights went out: One-third of the lights stayed on throughout that excruciating half hour. That probably means that the uninterruptable power supply system worked as planned. The only problem was that the UPS system was sized to one-third the necessary power needs of the stadium.
The lights weren’t the only things going out: The CBS announcers lost power, as apparently did the top-level cameras and the coaches’ communications systems. This points to a failure in wiring the building’s critical circuits. By far the most important thing to keep going in the case of an emergency (after emergency lighting and the PA system, both of which worked) is the power to the television operations. Television is what pays everyone’s bills, so that should have priority over other systems. It did not. Likewise, the fact that one team’s communications systems continued to work (the 49ers) and the other’s didn’t (the Ravens), showed that someone didn’t think very clearly when designing the critical circuit design.
LEDs still shone: If you looked carefully at the scenes of the blackened sections of the stadium seating, you could see that the emergency stair lights were all still lit. Likewise, the exterior colored lighting that bathes the outside walls of the stadium in light was still working. That’s because it’s made up of LEDs, which consume a fraction of a percentage of the power required by the sodium high intensity discharge (HID) lamps used for the rest of the stadium lighting. Additionally, the sodium HIDs, once they went out, took another 20 minutes to regain their full luminosity. LEDs, on the other hand, require no warm-up time and sip so little electricity that managing the current for them is a much less complex task.
Engineers and Repairmen
Based on this knowledge, here are three important lessons learned from the power management debacle that was Super Bowl XLVII:
- Right-sizing a UPS backup microgrid is about more than just installing a bunch of generators. The art of designing a backup microgrid is about balancing the maximum number of diesel gensets with the minimal amount of load. Physical space for backup gensets is almost always limited (especially in a flood plain like New Orleans, where generators have to be placed – at a minimum – on the second floor). Thus, keeping the blackout from happening was more of a failure of critical circuit design than of generator management.
- Energy efficiency counts more than backup power in times of emergency. The failure of the sodium HID lights and the long warm-up time they require would have been solved by energy efficient LED lights, which also would have reduced the load on the UPS system.
- Electrical design engineers are always more valuable than electric repairmen. Designing the critical circuits to be prioritized during a power failure is a job worth doing right, as we saw on Sunday evening. The designers of the Superdome’s UPS circuitry got some things very right: the success of the emergency lighting system kept the crowd from panicking. But the problems with the broadcasting and team communications systems showed that not everything was so well-planned.
Tags: Building Systems, Distributed Generation, Energy Efficiency, Energy Management, Microgrids, Smart Energy Practice
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