LED warehouse lighting offers superior levels of energy efficiency. LED high bay lights offer superior controllability, durability and reliability, making them particularly attractive for industrial lighting applications.
Warehouses are a major component of any commercial logistics system and have evolved due to the increasing complexity of functions, performing multiple tasks such as logistics, packaging, labeling, order picking, shipping and receiving, light assembly and desk work in a large space. In today’s dynamic business environment, warehouse facility management has become a highly specialized operation for manufacturers, wholesalers, retailers, importers, exporters, courier services, transportation and logistics companies.
As an essential component of any commercial logistics system, warehouse lighting plays an integral role in maintaining tight control over operating costs and task productivity. Industrial warehouses, logistics buildings and commercial distribution centers perform a highly diverse range of inbound and outbound processing activities and therefore place very specific and challenging requirements on lighting solutions to reduce operating costs while increasing efficiency.
A well-designed lighting system is essential to promote worker visibility, productivity and safety. In order to develop warehouse lighting solutions that meet performance requirements, operational and maintenance criteria, a robust set of quantitative values and qualitative variables must be considered.
Conventional Lighting Systems
HID lighting fixtures, such as mercury vapor, high-pressure sodium, and metal halide lamps, have been widely used for warehouse lighting because of their extremely high light output. However, HID lighting has inherent disadvantages such as excessive energy consumption, poor color expression, unsatisfactory lamp lumen depreciation (LLD), susceptibility to damage from shock and vibration, no color temperature selection, high optical losses, limited dimming capability in time and range, and lack of efficient electronic ballasts to power HID light sources.
An alternative to standard HID lamps for warehouse lighting is the fluorescent lamp, which emits diffuse light from a long glass tube. The disadvantages of traditional linear fluorescent lamps are high power consumption, short life expectancy, the need for a large number of fixtures to illuminate large areas, which increases initial installation costs, and poor quality light output in terms of color temperature and color rendering.
More efficient high-intensity compact fluorescent lamps or CFLs allow fluorescent lighting systems to be used in commercial, institutional and industrial spaces with ceiling heights below 15 feet. Although compact fluorescent lamps have many limitations compared to HID and external ballast-regulated fluorescent lamps, such as low brightness, relatively short life, short-wave ultraviolet (UV) emission, and poor compatibility with most dimmers, motion sensors, photocells, and timers.
Light Distribution and Task Visibility
Industrial warehouse spaces have large geometries and often use shelving systems arranged in basic parallel to maximize the available storage space to reduce storage costs. Confined space conditions and tall, narrow aisles often pose challenging lighting conditions, requiring uniform lighting and high vertical illumination for optimal identification of inventory goods from all viewing angles.
Warehouse applications present many different types of visual tasks, including reading labels on aisles, bins and products; sorting and picking merchandise by hand or with a forklift; light assembly and labeling of inventory products; and reading paperwork or keyboard input. These multiple tasks make lighting design a challenge because the nature of the storage area defines the task plane and proper task lighting is critical for workers to safely, efficiently and accurately perform key visual tasks.
Achieving proper task visibility requires adequate illumination (or light levels), sufficient contrast and color difference. Visual comfort considerations involving discomfort glare, overhead glare and flicker are decisive for task performance and workplace safety.
Energy Efficiency and Maintenance Cost
In today’s competitive global warehousing and logistics market, maintaining a strict energy budget can mean the difference between profit and loss. Industrial warehouse spaces, such as open storage facilities and high-bay buildings, often span vast areas. Multiple lights are installed to provide a generous range of lighting.
Warehouses are often elevated facilities with ceilings that can reach 30-40 feet high. At such heights, warehouse lighting fixtures need to provide more brightness with an intensity distribution appropriate to the width of the aisles and the height of the stacks.
Warehouse fixtures are often designed to operate at several hundred watts of power to provide a sufficient amount of light. Depending on the industry, warehouse lights operate from 10 to 18 hours per day.
Excessive fixture installations, high power consumption and long operating hours make warehouses energy-intensive buildings, with lighting accounting for two-thirds of the electricity bill. In addition to excessive energy consumption, expensive lighting maintenance is another major component of the life cycle cost of a warehouse lighting system and should be considered along with energy costs as the total operating expense of the facility.
Maintenance costs are those associated with the ongoing management and upkeep of the lighting system over its life cycle. As warehouses become more automated, the requirements for lighting are increasing, leaving facility managers with the challenge of finding lighting systems that are economical, functionally reliable and easy to maintain.
Warehouse Types and Lighting Requirements
There are various warehouse areas and storage facilities that may arise in warehouse use that require specific tasks. Open storage warehouses are open space storage areas that do not use a racking system and typically place storage on the floor and on pallets that may be stacked on top of each other. Open storage areas typically use general area lighting that provides a balance of vertical and horizontal lighting.
High-level storage facilities are generally automated, and storage bins may be rotated so that unused bins remain elevated. Warehouses with fixed shelving systems are high-capacity shelf storage that has multiple shelf spacings that create aisles between adjacent shelves.
Preferably, the light source for the high floor and shelving system is linear, with the length of each linear light approximately equal to the length of the aisle on which the fixture is mounted.
Mobile racking storage systems are a space-saving and cost-effective alternative to fixed pallet racking applications, with the entire racking block moving on floor-mounted tracks, opening and closing aisles as needed.
High-density storage solutions that optimize the use of available space often employ intelligent lighting systems that automatically turn on lights when aisles are opened. Cold storage facilities require lighting fixtures with a higher level of protection is mandatory in cold storage, with stable performance even at low temperatures.
Benefits of LED Lighting for Warehouses and Industrial Facilities
The lighting industry is moving away from energy-intensive and inefficient light sources. Advances in solid-state lighting technology and advances in optics and materials science have sparked a revolution in the high power lighting market.
The introduction of light-emitting diode (LED) lighting systems is driving aggressive lighting upgrades in commercial and industrial facilities. LEDs are known to be semiconductor diodes that emit narrow-spectrum light or electroluminescence by exciting electrons and holes across a biased p-n junction. Light emitting diodes are superior to gas discharge lamps in terms of light efficiency, luminous efficacy and lumens per unit.
LED lighting offers many advantages over gas discharge lamps, including: low energy consumption, high photon flux efficiency, narrow band luminescence, improved robustness, long operating life, small size, fast switching speed, and greater flexibility in assembly than traditional light sources.
For facility managers, there are three components to the cost of warehouse lighting, the first component (purchase and installation) costs, lighting maintenance costs, and electricity costs.
While HID and fluorescent lamps are relatively inexpensive to purchase, they are expensive to power and maintain because of their poor energy efficiency, low luminous efficacy, limited operating life, and systems that prove unstable in extreme environments. Unlike conventional lighting, LED lighting offers excellent durability and reliability, high output at higher drive currents, excellent controllability, and stable performance in cold storage environments, making it particularly attractive for warehouse lighting applications.
The lower energy consumption and maintenance costs and longer life with LEDs shorten the payback time and pay for lighting retrofits or upgrades over time.
LED Warehouse Lighting Fixtures
For most warehouse lighting applications, the primary functions of an industrial luminaire are to
1) precisely control the distribution of emitted light to ensure consistent optical alignment and provide repeatable photometric performance;
2) aesthetically modify the appearance of the light source by providing an overall design based on optoelectronic characteristics, which includes the thermal environment, knowing that the performance of LED lighting is very dependent on junction temperature;
3) mechanically support the electrical and optical components and securely fastens the luminaire to its mount for rugged industrial applications.
UFO LED high bay lights are the most prevalent lighting fixture in open storage warehouses and industrial and mining facilities.
While there are inherent differences in lighting technology, the commercialization of LED luminaires began with a similarity in form factor to luminaires using traditional light sources. Thus, the traditional round LED I&M lamp is a reflector lamp that mimics the shape of a metal halide I&M lamp, which relies on a reflector to shape the beam pattern.
The disadvantages of round reflector type I&M lamps are low optical efficiency because they use secondary optics and excessive physical size due to the use of bulky reflectors and heat sinks. The entire luminaire looks outdated and clumsy and does not fit into modern architectural designs.
In addition, the large number of thin aluminum reflectors required special care in separate packaging during shipping, which further increased shipping costs.
Modern high bay lights, often referred to as UFO LED high bay lights, are low profile, durable and styled to match modern commercial, retail and industrial environments. Precision molded acrylic lenses for the LED light engine are indexed to the board to output optimized distribution, eliminating the use of secondary optics for wasted light and providing optimal fixture spacing and improved uniformity.
UFO LED high bay lights, with their dust and moisture resistant design and electrostatically applied thermoset polyester paint, are excellent for use in harsh industrial applications with dust and moisture.
Thermal Management and System Stability
When selecting LED warehouse lighting equipment, it is important to consider its thermal management design.
In LED operation, heat is a byproduct of converting electricity into light, a process that excites photoluminescent phosphors in response to optical input energy. Phosphors that exhibit luminescence tend to degrade over time due to exposure to accumulated heat.
The optical performance and life cycle of an LED light source may be adversely affected by temperature. The level of light output from a typical LED is determined by the amount of current supplied to the LED.
Most industrial lighting applications require high brightness output, which can be achieved by significantly increasing the drive current of the light source. Therefore, effective thermal management is critical for high-power LED lighting systems.
Lighting Control
The economic benefits of switching to LED lighting in warehouses and industrial facilities can be further multiplied because of the excellent controllability of LED equipment.
With properly designed electronic control systems, LED lighting systems can automatically and efficiently harvest daylight to reduce energy use, flexibly adjust light intensity, or turn lights on and off at pre-designated times in pre-designated areas.
Many traditional warehouse lighting solutions, especially HID lights, have poor compatibility with advanced sensors and wireless controls.
Dimming and integration with occupancy sensors and photocontrols offer superior advantages for LED lights to improve energy efficiency and user satisfaction. Intelligent warehouse lighting systems take an integrated approach by communicating through multiple protocols over a variety of communication channels.
The lighting control system provides budget-conscious industrial customers with a reliable warehouse lighting solution for superior levels of energy efficiency, as well as high-quality lighting and network control capabilities.