Cree Lighting says that the new XSP outdoor fixture offers double the lumens per dollar relative to prior Cree street lights. Vice president and general manager Christopher Ruud said, "The payback of the fixture will be before the first relamp," meaning the time it would take a legacy HID lamp to fail. Ruud said that lowering cost is imperative given that stimulus funds are largely spent in the US. 

 

Payback is dependent both on the initial cost of lighting and energy and maintenance savings. The XSP design addresses both. Ruud said that the fixture offers optical efficiency greater than 90% and system efficacy as high as 100 lm/W. Lower luminaire costs, meanwhile, come through lower-priced and higher-performing LEDs, and the new optics design. 

 

The optic design builds on technology developed originally by BetaLED called NanoOptic. Cree acquired the BetaLED brand of SSL when it bought Ruud Lighting last year, and is now announcing a technology that it calls NanoOptic Precision Delivery Grid. BetaLED had been a pioneer in TIR optics designed to reliably control SSL beam patterns. 

 

The new design molds an array of TIR lenses into a single optic that covers five light sources arranged in an "X" pattern that's visible in the nearby photo. 

 

The new design offers Cree considerable flexibility in delivering many different lumen packages. Luminaire designers can use one