Cree Shatters Efficiency Benchmark with First 200-Lumen-Per-Watt LED Luminaire

[slebans]

http://www.cree.com/News-and-Events/Cree-News/Press-Releases/2014/January/200-LPW-fixture

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The 3,200-lumen concept luminaire delivered greater than 200 LPW at 80 CRI at thermal equilibrium while remaining within the ANSI color specification for 3000 K. The innovations behind the concept luminaire will enable Cree to deliver increased performance in LED luminaire applications at a lower cost to accelerate LED adoption.

 

[MTerrence]

That is absolutely fantastic. How does this compare to a typical high-pressure sodium lamp used in streetlighting fixtures? One would think that the combination of high CRI, more natural colour temperature, long lifespan and excellent efficiency could make it an attractive option for streetlights in the future.

 

[jtr1962]

That is absolutely fantastic. How does this compare to a typical high-pressure sodium lamp used in streetlighting fixtures? One would think that the combination of high CRI, more natural colour temperature, long lifespan and excellent efficiency could make it an attractive option for streetlights in the future.

HPS at best is about 125 lm/W. That's for the lamp only, before ballast losses. Moreover, because a HPS lamp is basically a 360 degree source, more that 1/3 of the light doesn't go where you want it. Overall, you're lucky if a HPS streetlight does better than maybe 80 lm/W putting light where you want it. A fixture like Cree made is over 2.5 times more efficient. Just one caveat-3000K is downright awful for streetlighting because low CCT kills peripheral vision. It also drapes neighborhoods in an ugly yellow haze. The trend is towards 4000K to 5000K for streetlighting. This give a more natural look, better peripheral vision, but doesn't produce a lot of glare like 6500K lighting would.

 

[MichaelW]

5000K would be terrible for night time residential lighting.

 

[18650]

5000K would be terrible for night time residential lighting.

Metal halide street lighting between 4000-5000K looks white and quite nice.

 

[idleprocess]

5000K would be terrible for night time residential lighting.

5000K (or something close to it - I have no spectrometer to peer at streetlights with) is commonplace enough with the various non-sodium arc lamps. There is a mix of sodium and metal halide in my neighborhood - thankfully mounted low enough and typically hooded such that they primarily light the street with minimal spill into yards and windows.

In terms of safety there are trade-offs with CCT. As I understand it higher CCT (4000K and up) offers better color rendition along with better depth perception and general object recognition while lower CCT (ala the ~2200K of most sodium lamps) better preserves night vision allowing for better situational awareness. As much as I dislike the ~20 CRI pallor of sodium lamps, they seem to have their place on highways and higher-speed roadways where drivers must react quickly to stimuli. Higher-CCT lighting seems best limited to slower-moving streets where the window to react is greater and there is ambiguity to the roads relative to highways and higher-speed arteries.

Higher-CCT outdoor lighting arguably disrupts circadian rhythms (humans and wildlife alike) more than lower-CCT, but there's already so much of it out there as-is that I imagine a good deal of the damage has been done.

I should add that I'm no lighting professional nor expert.

 

[BirdofPrey]

Our entire city switched to LED Street lamps around a year or so ago . The lights are very cool in the color spectrum.

I would have to guess at a minimum of 5k but possibly higher.

Sent from my ridiculously large Galaxy Note 2.

 

[BirdofPrey]

Apparently can't delete a post from my phone?