Solid-State Lighting Program at the LRC
An objective, international resource for solid-state lighting research since 2001
Now expanding SSL research toward greater benefits from the Internet of Things (IoT) and 3D printing
Solid-state lighting (SSL) has evolved to a point where the light-emitting diode (LED) is now the preferred light source for many lighting applications. The LED lighting system is a mostly mature technology, and LED market transformation is estimated to approach 50% by 2025. Organic light-emitting diodes (OLED) for lighting applications are also on the horizon. Research and development work is now moving toward exploring how SSL can be customized and how to use lighting to gather information that provides greater value to both producers and users.
The Lighting Research Center's Solid-State Lighting Program team is expanding its scope of research and educational programs to enhance this technology, overcome barriers, and show benefits beyond energy savings.
In 2015, the LRC set a new course to support the SSL industry through research that shows the value of lighting. Embracing the trends toward customization and data analytics, SSL research is now evolving to include new developments such as the Internet of Things (IoT) and 3D printing – areas where the lighting industry can both find and add value. The SSL Program’s multidisciplinary staff will be focusing its efforts in the areas of lighting systems and components research, data analytics, field demonstration and market transformation activities, education, and industry collaboration. Below are a few of the research areas and projects undertaken.
IoT and Connected Lighting
As just one piece of the extensive IoT field, connected lighting is defined as the connection of lighting, controls, and sensors to a local network that can be monitored and controlled, either wired or wirelessly, through a dashboard accessed by a computer, tablet, or smartphone. The lighting system may or may not be connected with other building systems, such as HVAC and security systems. Connected lighting systems are new and still evolving, and as such are mostly untested and have not been compared in the field with traditional lighting controls. Projects include:
Demonstration and Evaluation of Energy-efficient LED Lighting Controls
Remote Monitoring of LED Lighting System Health
In this ongoing two-year project, the LRC is evaluating LED lighting with fixture-integrated and network-connected lighting controls. The controls are being tested in a broadbased laboratory and field evaluation to compare and quantify the additional benefits that connected lighting systems offer to users. The LRC team will investigate everything from ease of installation to user satisfaction, evaluating what types of networked and fixture-integrated systems work best for different types of spaces, and will produce results and best practices guides for both purchasers and manufacturers. Sponsored by New York State Energy Research and Development Authority.
The LRC is exploring the ability for remote monitoring, whereby data is gathered to monitor the “health” of the lighting system. Such capabilities provide building managers with the benefit of early warnings that allow for timely scheduling of maintenance and replacement of lighting fixtures. Current investigations include the development of a methodology that allows for real-time prognostic health monitoring of an LED lighting system using wireless data transfer to a smart device. This includes analyzing wireless methods that can best communicate and map luminaire location, and determining sensor communication protocol requirements for reliable transmission of sensor data to a monitoring system.
3D Printing and Customization
3D printing, also known as additive manufacturing, allows objects of almost any shape or geometry to be manufactured from digital model data. One value of 3D printing for SSL is the ability to design custom lighting fixtures that match the architectural features of a building and then “print” or manufacture them on-site for quick installation. 3D printing also can be beneficially utilized at the fixture component level. With 3D printing of fixtures, heat sinks can be designed to be part of the fixture envelope rather than attached afterwards, which would reduce the fixture’s bulk size and cost and improve its attractiveness. Projects include:
Tailoring Material Properties
The LRC team is examining how fixture materials can be customized with the right amount of directional thermal conduction properties, allowing for the production of custom SSL fixtures within the additive manufacturing process.
Exploring Innovative OLED Luminaire Design
The LRC explored design opportunities for OLED panels using 3D-printed, modular fixture housing. Sponsored by ASSIST.
Systems and Components
Systems and components research seeks to understand the performance, benefits, and limitations of all the pieces that constitute a lighting application. Projects include:
Predictive Life Test for LED Systems
Believe it or not, the lighting industry still does not have an accurate method for estimating how long an SSL product will last in a given application. After several years of research investigating the life of LED lighting systems, the LRC has now developed a proposal for an accelerated, predictive life-test procedure that accounts for both lumen depreciation and catastrophic failure of a system at any given environment temperature and use pattern. Sponsored by Bonneville Power Administration, New York State Energy Research and Development Authority, and ASSIST.
Color-tunable LED systems
LED systems capable of spectral tuning are becoming more common. Their value is in the custom dynamic or static control of light color and dimming to accommodate tje changing needs of occupants within a space. Expanding the applications for color-tunable systems requires understanding application needs. The LRC has conducted research to characterize the performance of LED white tunable systems, to understand preferences for correlated color temperature, and to develop strategies to compensate for RGB system color shift. Sponsored by ASSIST.
The LRC’s Solid-State Lighting Program is led by LRC Director of Research N. Narendran, Ph.D., who also oversees the LED Lighting Institute, a professional education program in solid-state lighting available twice a year at the LRC laboratories in Troy, New York.
What is Solid-State Lighting?
Lighting applications that use light-emitting diodes (LEDs), organic light-emitting diodes (OLEDs), or light-emitting polymers are commonly referred to as solid-state lighting (SSL). Unlike incandescent or fluorescent lamps, which create light with filaments and gases encased in a glass bulb, solid-state lighting consists of semiconductors that convert electricity into light. LEDs have been around for more than 50 years but until the early 2000s were used only in electronic devices as indicator lamps.
Technological developments in the last two decades have allowed LEDs to be used first in signal devices, like traffic lights and exit signs, then in some limited illumination applications, such as flashlights, and now for many general illumination applications, from homes to commercial spaces to outdoor lighting. Since 2001, the Lighting Research Center has been instrumental in conducting research to make this transformation happen.
Why Solid-State Lighting?
Solid-state lighting is used in a variety of lighting applications because it offers many benefits, including:
- Long life — LEDs can provide 50,000 hours or more of life, which can reduce maintenance costs. In comparison, an incandescent light bulb lasts approximately 1,000 hours.
- Energy savings —The best commercial white LED lighting systems provide three or more times the luminous efficacy (lumens per watt) of incandescent lighting. Colored LEDs are especially advantageous for colored lighting applications because filters are not needed.
- Better quality light output —LEDs have minimum ultraviolet and infrared radiation and can be tuned to any color appearance.
- Intrinsically safe — LED systems generally are low voltage and cool to the touch.
- Smaller, flexible light fixtures —The small size of LEDs makes them useful for lighting tight spaces. OLEDs are flat and flexible, allowing for unique applications.
- Durable — LEDs have no filament to break and can withstand vibrations.
Solid-state lighting promises to change the way we light the world. The LRC is looking for answers to the challenges and opportunities offered by solid-state lighting. Visit the Key Research Accomplishments and Recent Projects pages for more information on the LRC's solid-state lighting projects.