Energy costs are a large operational expense for schools and universities – comprising the second-largest such expense for school districts, after teacher’s salaries. What’s more, lighting has been underutilized as a classroom tool, despite clear evidence that adjusting light levels and quality to the task at hand can improve student performance.
A project funded by the Department of Energy (DOE) is developing an energy-efficient light-emitting diode (LED)-based lighting system for classrooms that can be easily controlled to optimize student performance. The result of a DOE-facilitated partnership between RTI International and Finelite, the integrated next-generation system makes it easy to control light levels and chromaticity (the color of the light) in three classroom zones. It also incorporates what’s known as “daylight harvesting,” which is the use of daylight to supplement artificial lighting to further reduce energy consumption.
Designing lighting for educational settings presents significant challenges, due to strict performance requirements and tight budget constraints. Such lighting systems have to be not only affordable, but also flexible enough to serve varied teaching activities, and easy to use by students, teachers, and school staff. LED lighting has the potential to be more energy-efficient and longer-lasting than conventional lighting, plus it has the added advantage of being much more easily controllable, because it’s based on semiconductors rather than on filaments, plasma, or gas.
“In addition to demonstrating the excellent efficiency of LED lighting technologies, this project is expected to create interest in the unique color-adjustable capabilities of LED lighting,” says Dr. Lynn Davis of RTI International. “Educational settings are a perfect environment for this demonstration, since an adjustable lighting system can be used as a tool to calm students and to get their attention.”
An energy-efficient LED lighting system can also provide optimum illumination for the varied tasks carried out in the modern classroom, such as viewing video monitors, using computers and tablets, and taking notes during lecture presentations. However, the vast majority of today’s classrooms can’t make any adjustments to the lighting, other than to turn it on and off.
The performance targets for the made-in-USA system include full dimmability, long lifetime (greater than 60,000 hours), high energy efficiency (more than 120 lumens per Watt), a color range from “cool” blue-tinted white light to “warm” red-tinted white light, and good ability to show the true colors of objects. In addition to tackling key technological issues that have been encountered, the project is also focusing on keeping costs low and providing a user interface that balances flexibility with ease of operation.
The project has already demonstrated color-tunable LED lighting fixtures for the educational market that greatly exceed the energy efficiency of competitive technologies. The technology can already meet nearly all of the DOE requirements, and accelerated testing is underway to demonstrate its lifetime. Fixture fabrication has begun, and the team is constructing a mock classroom demonstration site that will enable the holding of focus groups with potential users and stakeholders. The project is proceeding ahead of schedule to deliver a domestically produced lighting solution for educational markets.
- RTI International and Finelite Inc.
- Classroom lighting at the preschool, primary, secondary, and post-secondary levels
- Energy efficiency of more than 120 lumens per Watt
- Lifetime greater than 60,000 hours
- Easily controllable color range from “cool” bluish-white to “warm” reddish-orange
- Fully dimmable
- Joel Chaddock, solid-state lighting project manager, NETL
- $450,000, with a cost-share of $150,000