The high intensity discharge (HID) lights in the Superdome contributed to the length of the play delay at the Super Bowl, according to the US Energy Information Administration.
High levels of light output require more energy, and since HID lights provide 75 lumens of light per watt, they make an efficient choice for outdoor applications and large venues, such as warehouses and sports areas. But one disadvantage of HIDs is their long warm-up and restrike times.
As millions of viewers witnessed, last Sunday's Super Bowl had a 34-minute outage. The Mercedes Benz Superdome uses metal halide lights, a type of HID lamp, as its main overhead lighting in the arena. After the power outage during the game, it took several minutes for power to be restored and then more time for the lights to restrike, or achieve full brightness after being extinguished. Because of the way the lamps work, restrike times are often longer than initial warm-up times and can take 5-20 minutes to achieve 90 percent brightness.
According to the Lighting Research Center at Rensselaer Polytechnic Institute, some types of metal halide HID lamps use a different starting mechanism that can cut warm-up times down to 1-4 minutes and restrike times to 2-8 minutes.
Despite the inconvenience of long warm-up and restrike times, HIDs have their place. For instance, a 60-watt incandescent lamp will produce about 800 lumens of light output per lamp, and most residential and commercial applications only need each lamp to provide light levels in the range of about 800 to 4,000 lumens per lamp. But HID lamps can provide more than 15,000 lumens per lamp, making them suitable for large areas that need lots of light.
