The Lighting Research Center at Rensselaer Polytechnic Institute is evaluating light-emitting diode (LED) technology for use in commercial display freezers. The study, funded by the New York State Energy Research and Development Authority (NYSERDA), will evaluate performance, energy savings, shopper preferences, and product sales for this technology compared with the fluorescent lighting currently found in supermarket freezers.
The LRC is collaborating with GE's GELcore, the Golub Corporation (Price Chopper supermarkets), and Tyler Refrigeration (a division of Carrier Corp.) on this project. The team recently installed a four-door freezer with a prototype LED lighting system in the frozen-food aisle at an Albany, N.Y.-area Price Chopper supermarket.
N. Narendran, Ph.D., LRC director of research, says of the new field study, "To the best of our knowledge, this is the first freezer to operate with advanced white LED technology on a supermarket retail floor." During the next several months, LRC researchers will survey shoppers about the LED freezer and a similar fluorescent-lighted freezer to determine shoppers' lighting preferences. Shoppers will evaluate the attractiveness and the clarity of the merchandise within each freezer case. The LRC also will analyze sales data to determine whether the freezer lighting has any influence on consumers' buying habits. Results will be presented in spring 2005.
In a prior laboratory study, the LRC developed a prototype refrigerator lighting system using LEDs with the goals of reducing energy usage and producing better illumination for the merchandise. The results showed that the LED lighting system produced more uniform illumination on the displayed products and was strongly preferred by more people than traditional fluorescent lighting in this application. LRC researchers also estimated that when the efficacy of white LED lighting systems reaches 38 lumens per watt, LEDs will use less energy than traditional fluorescent lamps in this application. The efficacy of white LED lighting systems currently stands at approximately 24 lumens per watt and is expected to exceed 38 lumens within two years.
Finding more efficient ways to light freezer and refrigerator cases is important because supermarkets spend nearly half of their electricity costs on refrigeration. Though fluorescent lighting is generally considered energy efficient, these lighting systems do not perform well inside freezers, says Dr. Narendran. "Cold temperatures decrease the light output of fluorescent lamps and, at the same time, reduce their operating life," he says. The final result is increased power consumption and more frequent maintenance, which impact the overall cost of operating the lamps. Improvements in white LEDs, however, are showing potential for these light sources to have better efficiency than fluorescent lamps. "LEDs are not plagued with the cold temperature problems affecting fluorescent lamps, which means energy and maintenance costs can be reduced in the long run by using LEDs inside freezers," Narendran says.
Rensselaer Polytechnic Institute, founded in 1824, is the nation's oldest technological university. The school offers degrees in engineering, the sciences, information technology, architecture, management, and the humanities and social sciences. Institute programs serve undergraduates, graduate students, and working professionals around the world. Rensselaer faculty are known for pre-eminence in research conducted in a wide range of research centers that are characterized by strong industry partnerships. The Institute is especially well known for its success in the transfer of technology from the laboratory to the marketplace so that new discoveries and inventions benefit human life, protect the environment, and strengthen economic development. Visit www.rpi.edu.
GELcore, a joint venture of GE and EMCORE Corporation, is a leading provider of innovative LED systems and advanced LED technologies for the global transportation, signage, architecture and specialty lighting segments. GELcore advances the application of LED technology and creates world-class LED systems by combining superior engineering in electronics, optics and thermal management, and through the continued research and development of white LEDs for the emerging general illumination market. On the web at www.gelcore.com.
About Golub Corporation (Price Chopper)
Beginning in 1933 as Central Markets, Price Chopper was established in 1973 as the area's low price high quality supermarket operator. Since then Price Chopper has become involved in the communities in which it does business, and the Golub Foundation supports many community programs. Price Chopper stores serve communities in New York, Massachusetts, Vermont, New Hampshire, Connecticut, and Pennsylvania. On the web at www.pricechopper.com.
The New York State Energy Research and Development Authority (NYSERDA) is a public benefit corporation created in 1975 by the New York State Legislature. NYSERDA administers the New York Energy $martSM program, which is designed to support certain public benefit programs during the transition to a more competitive electricity market. The New York Energy $martSM program provides energy efficiency services, including those directed at the low-income sector, research and development, and environmental protection activities. On the web at www.nyserda.org.
About Tyler Refrigeration
Founded in 1927, Tyler is a leading provider of innovative, quality products. Its core product line consists of refrigerated and non-refrigerated merchandisers, walk-in coolers and mechanical refrigeration systems. The products manufactured at each of Tyler's seven factories support the refrigeration needs of supermarkets, convenience stores, restaurants, wholesale clubs, industrial and institutional facilities. Tyler Refrigeration is a division of Carrier Corporation. On the web at www.tylerrefrigeration.com.