QuestionDo LEDs make sense for a baseball field that sees only 10 night events per year? Does the technology offer better lighting quality as well as energy, demand, and maintenance cost savings?
LEDs would be the best choice, although there may be other options as well. LED benefits for this type of application include lower energy and maintenance costs, reduced demand charges, better controllability, better color quality, and less light pollution and light trespass. In addition, unlike metal halide lamps, LEDs are instant-on and have no restrike delay. It also takes some time for metal halide lamps to warm up to full output. E Source Technology Assessment Service customers can read the report LED Applications: Stadium and Arena Lighting for more information.
There is also the possibility to tune the color temperature. For example, the Stadium Pro product from Ephesus, which is the product used at University of Phoenix Stadium, offers a color temperature of 5,600 kelvins (K) or the ability to tune between 4,000 K and 6,500 K. That ability might be used to vary color from evening through night, to choose an optimum color for the teams playing, to change colors for seating and exiting versus game time, or for a seasonal variation. Also, the controllability and lower operating costs of the LEDs might open up the possibility of using the site for more than just a few games per year, such as for concerts and fairs.
The other option, depending on how old the existing system is, would be to look for a more efficient metal halide solution. For example, Musco claims its Light-Structure Green system with a metal halide light source and advanced optics can reduce energy costs by up to half and cut spill light and glare by 50% compared to typical metal halide floodlights. Qualite also offers an efficient alternative, GreenStar, which uses metal halide lamps with electronic ballasts. Other sports lighting vendors include General Electric, Philips, Ephesus, and Hubbell/Sportsliter.
The US Department of Energy article Play Ball! American Baseball Stadiums Round the Bases on Energy Efficiency says that “53% of North American professional sports teams have energy efficiency programs and more than 30% have incorporated renewable resources into their operations.” The report spotlights several energy-efficient ballparks, including Busch Stadium in St. Louis, Missouri, and Safeco Field in Seattle, Washington (Figure 1).
Busch Stadium. Through its 4 a Greener Game initiative, Busch Stadium—home to the St. Louis Cardinals Major League Baseball (MLB) team—has reduced its energy costs by 20%. The stadium has also installed more-energy-efficient HVAC and refrigeration systems throughout the facility.
Safeco Field. The Seattle Mariners were the first MLB team to light up its ballpark with LEDs, which reduce power usage at Safeco Field by 784,000 kilowatt-hours each season, saving more than $50,000 in energy costs.