Survey sez LED lit parking garages seem safer

We had a sneaking suspicion that there was an ulterior motive behind Raleigh getting lit up as the "world's first LED city," and aside from savings tons of dough on energy bills over the next decade or so, it seems to make motorists feel a good bit safer, too. According to a before and after survey conducted by Mindwave Research, the number of respondents who "perceived the garage as very safe increased by 76-percent after the LED fixtures were installed." Admittedly, the newfangled lighting certainly added a new level of brightness to the situation, and the number of individuals who gave the garage an overall rating of "excellent" increased by 100-percent in response. The (unnecessarily lengthy) survey also added a few more minor figures to further prove that LED lighting is simply superior to the other stuff , but we're not yet sure if Cree will successfully use this ammunition to grab even more contracts to freshen up the city lights.

[Karl @ Mar 30th 2007 9:20AM]

If that picture is the garage in question, then it appears to have been using sodium discharge lighting in the before picture. Sodium lights work much more like fluorescents and are themselves very efficient, so this is hardly an indictment of incandescent lighting. A little fact-checking goes a long way...

[NeoteriX @ Mar 30th 2007 10:41AM]

And reading the articles goes a long way too.

"In a pilot program late last year, LED lights were installed in a parking deck downtown. Progress Energy, the city’s primary energy provider, said that the floor equipped with LED lights used more than 40 percent less energy than the standard lighting system. Also, the quality of the lighting was greatly improved, according to Progress Energy’s research."

Click on the "World's First LED City" link in the body of the Engadget article.

[Karl @ Mar 30th 2007 10:45AM]

Yes, I read the article, and yes LEDs are more efficient (and less toxic) than fluorescent or discharge lights. But again, none of the lights in question are incandescent lights, as implied in the write up.

[Lewis Salem @ Mar 30th 2007 9:50AM]

What is important about this study is that it can be used as a tool to give the mainstream media some positive press about LED adoption.

[kizane @ Mar 30th 2007 10:48AM]

Yes, those are definitely high pressure sodium lamps (cliking on the pic confirms this), which are used in areas where color rendition isn't a priority, like in this garage. HPS lamps put out around 100-150 lumens per watt consumed and a life of 20,000 hours ( http://en.wikipedia.org/wiki/Sodium_vapor_lamp#High_pressure_.2F_HPS ), where as these Cree white LEDs are putting out 131 l/w with a life of 100,000-1,000,000 hrs (but I've seen plenty of traffic light LEDs dying, probly due to the control circuit), according to the article: http://en.wikipedia.org/wiki/Light-emitting_diode

So... depending on how efficient the existing HPS lamps were, they may have increased their electricty bill (actually, I'm sure they did since there is way more coverage than before), but "should" have decreased the maintenance bill...

[kizane @ Mar 30th 2007 10:51AM]

Don't get me wrong, though... my wife thinks I love LEDs more than her!

[kizane @ Mar 30th 2007 10:51AM]

Don't get me wrong, though... my wife thinks I love LEDs more than her!

[Vincent @ Mar 30th 2007 10:52AM]

When it comes to safety, it's more to do with the actual colour of the lights, since over here they're replacing the yellow lights at railway stations with white ones simply because they give a greater perception of safety.

As for the LEDs, if they're saving money then it can only be a good thing.

[Geoff @ Mar 30th 2007 11:14AM]

I'm all for saving energy, especially when lights are on 24 hours per day. You would think they would have used less lights since they seem brighter, and that way they could have used even less electricity.

[Revrant2394 @ Mar 30th 2007 11:45AM]

Everything else aside...Gosh, look at the difference there though, it looked like something out of Nightmare On Elm Street in the before picture, that's why I never use parking garages around here, they give me the heebie jeebies.

[soundboy64 @ Mar 30th 2007 12:15PM]

If everyone ultimately moves over to LED lights in parking garages, where are we filmmakers to go when we need to shoot creepy parking garage scenes with the types of people your mother warned you about?! Think of us!

[waif69 @ Mar 30th 2007 2:10PM]

The filmmakers can do what they have always done, either use a filter, adjust in post-production, put in their own lights or film on a sound stage.

[Jeff @ Mar 30th 2007 1:01PM]

Thing about those photos is your eyes can adjust somewhat to the color cast. If the camera had white balanced each of the shots, they would look more similar.

[Peter @ Mar 30th 2007 1:36PM]

Uhm, very exciting. First you dimly light a garage with high pressure sodium lamps, then switch to white and increase the brightness. Surprisingly people find this more comforting. Wow.

Any other white light and increase of brightness would have that same effect, so the message about LEDs is zero. Also not mentioned is the certain fact that the new lights use more electricity instead of less, and fortunately they spared us the shocker-price as well.

Talking efficiency and lifespan: the mentioned wikipedia numbers are maximum values of prototypes, i certainly wouldn't expect anything close in a mass-production product, especially not in high-power applications where lifespan and efficiency are usually compromised by space and cooling constraints. Unsurprisingly, the datasheets on Cree's website fail to mention any such details.

[Peter @ Mar 30th 2007 1:50PM]

Ah, and here we have the fixtures installed in Raleigh:
http://www.lsgc.com/brochures/LOWBAY%20FIXTURE.pdf

75W for 2500 Lumens effective output - meaning a pale 33 lm/W, which is low even considering that this is after fixture losses.
50khours rated life, however no info what survival rate they specify at this time. Oh, and you'll have to replace the entire fixture after that rather than changing a bulb. Looks like an expensive wakeup-call 6 years from now...

[soundboy64 @ Mar 30th 2007 3:38PM]

The thought of using a filter in a brightly lit parking garage to get a dingyily yellow lit shadow infested parking garage is almost laughable (try doing day for night on a sunny day (doesn't work very well)). and for an indie filmmaker to just have the money for their own lights on top of getting a parking garage manager to turn off all of the existing lights for them is next to impossible, which brings me to my next point of filmming on a soundstage and building your own parking garage set, (if you know of a money tree, please, point me in the direction)

[Zepolcire @ Mar 30th 2007 2:47PM]

I think they put too much light in there. Since the LED lights are so bright, they should have put in less to make it not as harsh for the eyes to adjust to when parking at night. Kinda like when your on the freeway at night and you drive by a part of construction where they use lots of flood lights. Man that hurts my eyes. Also, this is adding to light polution. If a city uses this in all parking garages, your just going to have a city dotted with bright buildings.

/misses looking at stars....

[SuperchargedOmar @ Apr 2nd 2007 3:19PM]

Another reason for sodium lights is that Sodium lights cut out the amount of ambient light that enters the night time sky ( light pollution) which can make stars harder to see at night. Where I live, San Jose, Ca, it is essential to have sodium lamps because on our highest peak there is a Observatory so there needed to be a check on light pollution otherwise that excess lighting would light up the cloud cover, fog, and all the stuff in the sky making it hard to see any stars. Just my two cents.