High bay lights are a major contributor to the lighting environment of indoor sports facilities where the number of spectators is small or where the compactness of the building structure poses a problem for the use of floodlight fixtures.
Typically, these luminaires are installed in gymnasiums and sports arenas. Gymnasiums are often implemented as part of educational facilities to host school programs and sports activities.
Gymnasiums are wide indoor spaces designed to host entertainment plays, training programs or competitive plays that do not attract large audiences.
These spaces are used to accommodate a variety of sports such as basketball, badminton, tennis, volleyball, ice/roller field hockey, and futsal. Gymnasiums and sports arenas are often constructed using skeletons that form interior subspaces known as “bay”.
Lighting equipment is mounted on the surface of the ceiling structure or suspended by suspension devices. Because the clear height of these facilities typically reaches or exceeds 6.1 meters (20 feet), the lighting fixtures installed in them are often referred to as “high bay lights.
However, there is no hard and fast rule regarding the height of the ceiling involved in the installation of high bay lighting.The minimum installation height is determined by the type of movement within the space.
For example, luminaires should be installed at least 6.7 meters (22 feet) above an IES Class IV basketball playing surface.
There is a correlation between the size of a facility and the level of lighting.
Sports played in gymnasiums and stadiums typically require the quantity and quality of illumination to meet IES lighting standards for Class III or IV plays. The quantity of illumination is most often considered to maintain average horizontal illumination, which is a measure of the density of luminous flux incident on a horizontal surface or playing surface of 1 meter or more.
For aerial sports, vertical illumination should be evaluated over the entire height of the playing area to ensure good visibility of playing targets that are often in the air.
Quality factors of lighting include uniformity, direct and reflected glare, color rendering and light flicker. Uniformity of lighting is a universally important factor in all types of sports and at all levels of facilities.
Uneven lighting causes the eye to adjust between different levels of brightness.
Constant adaptation of the eye across the field of view can lead to visual discomfort and eye strain, as well as distorted visual perception of the speed and position of the competition target. Sudden changes in the amount of illumination in the race area can cause fast-moving targets to appear to speed up or slow down as they pass from one illumination level to another.
The ability to meet the quantitative and qualitative requirements of high bay lights in stadiums depends almost entirely on the performance of the luminaire.
While high bay lights are fixed lighting systems where the luminous flux distribution is completely controlled by the overall optical system, floodlights for large sports facilities offer more flexibility in optical design because they can be aimed in any direction.
To accomplish this task, high bay lights must produce a large number of lumens to meet illumination requirements, while providing tight beam control and uniform light distribution.
Historically, high bay lights in sports arenas used high-intensity discharge (HID) lamps (i.e., metal halide), which produce light through an electrical discharge in an arc tube. The use of metal halide lamps, while addressing the challenges of sports lighting and being more economical than incandescent lamps, has been controversial for several reasons.
When installed in luminaires, the modest efficacy of metal halide lamps is immediately offset by optical losses of 30% or more due to their omnidirectional radiation pattern and the larger size of the light source.
HID high bay lights place a large amount of light in the center of the beam spread, resulting in uneven light distribution. Therefore, the luminaire density needs to be increased to closely overlap with the beam produced by adjacent luminaires to achieve the desired uniformity.
HID high bay lights are inefficient and ineffective in providing light to their intended targets, resulting in high capital and operating costs. Maintenance of HID luminaires is complex, sometimes for the lamps and sometimes for the ballasts.
Metal halide lamps operate at high temperatures and pressures. To avoid catastrophic failure at the end of the specified lamp life, which is relatively short for high wattage lamps, a collective reload is required rather than replacing the lamps individually.
The costs incurred would exceed the initial investment. In addition, long warm-up and restart times, limited dimming capability, and rapid aging behavior under the stress of frequent switching prevent HID high bay lamps from achieving the energy savings potential of lighting control.
LED High bay lights are now being used in stadiums.
Semiconductor-based lighting technologies offer far-reaching opportunities to improve the efficiency, effectiveness, quality and reliability of lighting. The LED technology platform enables energy savings beyond greatly improved light source efficiency and includes Lighting Application Efficiency (LAE), which achieves energy savings through improved optical transmission efficiency, the use of lighting controls and optimized spectral power distribution (SPD) features.
By leveraging the unique characteristics of LEDs, high bay lights can be designed to go beyond traditional form factors and optical control methods to achieve highly uniform, precisely controlled light distribution and efficient luminous flux delivery of the light source.
The connected LED high bay lights system can utilize data collected from occupancy or daylight sensors, local controllers, personal devices such as smartphones, building management systems (BMS), IoT platforms, or any combination of these to implement sophisticated lighting control strategies to achieve maximum intensity results.
Other lighting attributes, such as color appearance, color rendering and flicker-free, can be prioritized when necessary to provide the best lighting for the application. In sports lighting applications, the trouble-free operation of hard-to-reach lighting systems is of decisive importance.
The ability of LED systems to perform the required functions under practically controlled operating conditions for long periods of time brings lighting to the forefront of reliability and sustainability.
Lighting systems typically generate, control and distribute light through a highly engineered architecture that contributes to the reliable, efficient and controlled operation of LEDs.
LEDs are p-n junction semiconductor devices that emit light through the intracrystal radiation recombination of charge carriers (electrons and holes). This property gives LEDs high quantum efficiency, excellent dimming and switching performance, and source-level optical controllability.
However, the performance and lifetime of LEDs are closely related to the electrical (current, voltage, power) and thermal (junction temperature) properties of the compound semiconductor structure, which create active regions for the onset of the injected electroluminescence effect.
In order for LEDs to achieve their intended value in real-world applications, the luminaire must create and maintain a compatible operating environment that provides proper drive current regulation, thermal management, mechanical engineering, and optical control for the LED.
The physical appearance of LED high bay lights can vary greatly, but the essential elements of a high performance LED system never change.
The formal elements of traditional high bay lighting systems are lamp-based designs that fail to take advantage of the unique features and address the design challenges associated with LED technology.
Advanced LED systems typically feature advanced physical integration of LEDs with heat sinks and optical systems, which improves the performance of the thermal path and maximizes the efficiency and effectiveness of optical transmission. The integrated design of LED high bay lights systems ultimately comes in two structural forms: fully integrated and modular. A fully integrated LED high bay lights emits light from a single optical assembly consisting of a heat sink, an array of LEDs populated on a metal core printed circuit board (MCPCB), and secondary optics.
Higher power versions may contain multiple LED arrays. Integrated LED luminaires with circular shapes are often referred to as UFO LED high bay lights.
The modular system is an assembly of modular LED engines. Each modular LED engine is constructed with the same optical components as a fully integrated LED luminaire, but has a form factor that facilitates modular integration. The modular design provides the scalability of a lumen package and the flexibility to customize the optical distribution to the application requirements.
Most sports lighting applications require high bay lights designed for direct lighting distribution. Direct lighting systems range in distribution from wide to concentrated.
Narrower beam distributions can be used for installations with higher heights or for applications requiring excellent glare control. The lumen distribution of LED high bay lights is typically controlled by a secondary optic that is mounted in such a way that it extracts light directly from the light source and produces a precise light distribution.