LED Under Cabinet Lighting

The objective of this study was to assess the status of the light-emitting diode (LED) undercabinet lighting and measure incremental energy and demand savings over their T8 linear fluorescent and incandescent counterparts. Photometric and power tests conducted in the Southern California Lighting Technology Center (SCLTC) demonstrate the differences and similarities of the baseline (fluorescent and incandescent) vs. measure (LED) cases. To supplement tests conducted at the SCLTC, a field study was conducted to understand how residences use their kitchen under-cabinet lighting. This study consisted of monitoring 26 houses in Southern California Edison (SCE) service territory, Sierra Pacific service territory, and Truckee-Donner Public Utilities District service territory. The data was used to help gain an understanding of the yearly operation of under-cabinet lighting. The focus of the study was the use of under-cabinet lighting in kitchen applications. The photometric and power data obtained through lab testing was combined with hourly usage figures to obtain energy savings, demand savings, and efficacy figures for the technology. Recent advances in LED technology have made them brighter and more efficient, thereby expanding the application of LED to the under-cabinet lighting market. In addition, some manufacturers have improved efficiency of the required AC-DC conversion process. This study assumes that the operation of the LED under-cabinet light is the same as that of the fluorescent and incandescent under-cabinet light from the perspective of the end-user. The measurements taken in the laboratory verify the energy and demand figures for baseline and measure cases. Measurements were also taken to compare other lighting characteristics of the LED vs. the fluorescent and incandescent under-cabinet lights. Since under-cabinet lighting is typically sold in different lengths, measurements are presented on a “per foot” basis. The total lumen (lm)/foot (ft) output of LED under-cabinet lamps range from 63 lm/ft to 291 lm/ft, which is below that of a T8 linear fluorescent at 320 lm/ft. Since the incandescent fixture tested at 145 lm/ft, some of the LED fixtures can be considered equivalent. The lm/foot output does not account for overall application efficiency. Since the LED tested products did not have similar lumen output as the T8 linear fluorescent, it is difficult to consider them equivalent using this metric. However, there were a few LED products that were comparable to the incandescent lamp. In addition, most of the LEDs had a greater efficacy than the incandescent lamp. Based on the tested LEDs and using hourly usage figures developed during this project, an annual savings of 22.97 kWh per linear foot of under-cabinet lighting was realized over the incandescent technology tested.