Because the Cree® LED luminaires provide better light levels over traditional fixtures, fewer needed to be installed at the South Lake Tahoe store and station than similar Raley’s® locations that use fluorescent, metal halide and halogen spot fixtures. The LED luminaires could also be spaced further apart by comparison to the traditional technology fixtures. Raley’s® and Hi-Def Lighting & Electric Inc. examined differences in the lighting by comparing overall fixture cost including installation time, controllability of lighting, circuit design, switching and energy usage per room or fixture zone. The result of the comparison revealed very minimal additional cost for purchase and installation of a complete Cree LED luminaire system.
The largest benefit of the Cree lighting installation is the energy savings that has exceeded expectations and contributed toward an impressive payback of only .95 year. The payback was achieved by comparing the energy use and maintenance for compact fluorescent, electronic ballast F32T-8 fluorescent, metal halide and halogen spot fixtures used at Raley’s® existing location in Fair Oaks, California to the new Cree LED installation, and factors in the cost of the luminaires.
Most Cree LED luminaires are a controls-ready lighting solution designed for compatibility with a variety of system protocols utilizing wireless and power-line carrier technologies. Cree luminaires offer an optional integrated occupancy sensor which can further reduce energy use through motion detection. This ability to dim many of the Cree luminaires is useful in conserving energy and achieving California’s requirement of controlling fifty percent of daylight use through off or dimming. In this case, instead of turning the luminaires off, daylight control sensors detect ambient light and dim them when they are not necessary. A lighting control system was selected that incorporates the Cree luminaire on-board occupancy sensors, timed schedules, ambient light sensors and wall switches for over-ride control. The external lighting control system is self-adjusting depending upon the amount of ambient light detected. For example, Cree 227 Series™ recessed soffit luminaires in the car wash bay operate at twenty-percent power until the occupancy sensor brings them to full power and dims them back down to twenty-percent when not in use.
An unexpected benefit of the Cree lighting installation proven to be very positive for Raley’s® operations are that the universal drivers that provide continuous illumination during unexpected brownouts common to the area. In South Lake Tahoe the voltage will drop as much as 30 percent numerous times during hot afternoons, creating multiple problems with electrical systems throughout the site. Fortunately, the Cree luminaires are unaffected by erratic voltage drops and continue performing at peak efficiency due to dependable drivers that include AC input protection that senses and accommodates for short-circuit and over-voltage.