|Fig. 1: Seattle's Safeco Field. Safeco Field is the first MLB stadium to implement an LED lighting system, which has encouraged others to do the same. (Source: Wikimedia Commons)|
One of the biggest challenges that we as humans face in our effort to reduce our energy consumption is balancing functionality with efficiency. That is especially true in the market of sports, where performance and functionality are valued more than the overall effort to reduce energy consumption. While energy consumption is definitely of some value to sports league executives and officials, a new technology will only be implemented if it is assured that it won't jeopardize the final product on the field. An example of a new energy technology that is both more efficient and more functional than previous technologies is the new LED light system at MLB's Safeco Park in Seattle, Washington. The lighting system, which was implemented in early 2015, reduces glare and shadows throughout the park, offering an improved atmosphere for both the players and the fans. It is the first Major League stadium to adopt an alternate method of illuminating a ballpark at night, and its success has encouraged other stadiums to implement LED lighting systems of their own. In the past, sports stadiums have used traditional metal halide lights, which you can see in Fig. 2, as a way to continue play into the night. While LED technology has been around for quite some time now, there were a number of concerns about its safety and readiness for use in a major stadium that ultimately delayed its integration.  However, attitudes on LED lights have changed in the last few years, as new stadiums are now being built with LED lights, while existing stadiums are beginning to make the switch to LED lights.
|Fig. 2: An example of traditional HID floodlights for illuminating playing fields. There is a growing trend towards replacing these HID lights with more efficient LED lights. (Source: Wikimedia Commons)|
Safeco Field's new lighting system replaced 579 metal halide lights, which can with 578 GigaTera SUFA LED fixtures, which you can see in Fig. 1. While the old metal halide lights ranged from 1,000 to 2,000 watts, the new LED fixtures use only 800 watts. Despite using 60 percent fewer watts than metal halide lights, the new LED lights are still 20-30 percent brighter. Additionally, the LED lamps at Safeco field last over 100,000 hours, compared to only 3,000 hours for metal halide lights.
There are a number of benefits to using LED lights over the traditional metal halide lighting system beyond energy savings. For one, metal halide lights need time to warm up.  This means that if a stadium decides to restart its lighting system, it would need about 20 minutes before play could be resumed, as opposed to LEDs which turn on immediately. Additionally, the LED lights at Safeco Field significantly reduce shadows and glare on the field, which are important for players, fans, and viewers on TV. On the Coloring Rendering Index, sun light scores a 100, the new LED lights register a 81, which is a significant improvement over the 63 that metal halide lights register.  The LED lighting system improves a player's vision and ability to track a baseball, which is crucial in a sport like baseball. This also benefits fans, who can now follow the game better with fewer glares and shadows. Lastly, this LED lighting system has been proven to enhance a viewer's TV experience by enhancing color and reducing the flicker in slow- motion replays. Another advantage that LED lights have over metal halide lights is that they have a much longer lifespan, which translates to savings in terms of maintenance costs.  Most importantly, each season, the newer LED lights will reduce overall power consumption by 784,000 kWh, which means more than $50,000 will be saved in energy costs alone.
Although experts were initially hesitant to implement LED light technology into a stadium setting due to safety and performance concerns, the initial reviews have been nothing but positive. Seattle's Safeco Field was the first MLB stadium to make the transition, and early observers predict the rest of the league's 31 teams to adopt a similar lighting system in the future. While LED lights have been generally accepted as the future of lighting, some researchers have speculated that LED lighting may have negative ecological impacts, which has called for ecologists and electrical engineers to collaborate in an effort to minimize potential ecological effects in future LED technology developments. 
© Mikey Diekroeger. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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