
Clovis and Fresno look a lot alike, so it’s hard to tell sometimes when you cross from one city to the other. The street signs are a good giveaway, as Fresno uses green and Clovis uses brown. But now, at night, there’s one other difference: Clovis is installing LED street lights at almost every intersection. According to the city, they are in the process of installing over 400 LED street lights. I’ve seen them at most intersections, although a section of Clovis Avenue, by Old Town, has all been redone.
Willow Avenue, the border between Fresno and Clovis is interesting. There are four lights at each intersection, and now two are LEDs, and two are sodium.
LED has a few advantages over the existing high pressure sodium lights. The most obvious one is color. The sodium lights are your standard yellowy-orange lamps that make it very difficult to see colors at night. LED’s, on the other hand, are very white.
At this intersection, you can see the lights mounted on the traffic polls have been switched. All the other lights are of the older kind
From my observation, the LED lights appear to be brighter than what they replaced. This is a very good thing, as the street lights here can be placed quite far apart. At intersections, the brighter light helps make pedestrians more visible. The better color clarity also makes it easier to distinguish what’s in the crosswalk.
The regular street lights are very yellow
There are a few other advantages to, besides color, and in this case, light output (light output will vary based on what model the city buys).
-Energy efficient. It’s not a huge savings, because the old sodium lights are pretty efficient themselves, but every bit helps.
-Longer lifespan. LED is much more expensive than the existing installations, but is supposed to have a longer life. The savings in labor should be enough to justify the switch, along with the energy savings
-Better light distribution. The LED lights are more focused, unlike the sodium ones which have three distinct bright spots, and then darker areas. The older lights have glare and create shadows, as seen in this comparison.
LED lights provide a more uniform coverage
I’m excited to see the new lights around Clovis. Hopefully the savings mean that they can continue the transition throughout the year.
The intersection has been done, and is very well lit, but there are thousands and thousands of street lights in the city. If you like the sodium lights, don’t worry, you’ll be seeing them for a very long time
One other thing I’d like to see the city experiment with are lights with solar panels, but that’s really something that PG&E has to push through. Maybe next year.
LED street lights would be cheaper and better.
LED Grow Lights
Hi all,
LED street light is a great cost-cutting technique that will save money for decades to come. The LED street lights generate a clean, low-glare light, which provides improved visibility over the traditional streetlights. The superiority of LED street light becomes unavoidable when environmental advantage is added to their extremely long life. Thank you.
Led Tunnel Light
The L.E.D. lights that Clovis has installed represent a gross step backwards in municipal street lighting when gauged against shielded and modern designs of high pressure sodium lighting. Not only do L.E.D. bulbs produce a very harsh and sharp light, but another issue is that the light they omit is directional in nature, much like searchlights. The problem with this nature is that L.E.D.s mostly light whatever they're pointed directly at; that's good for a flashlight, but bad for a streetlamp. This is because in addition to brightly illuminating the area underneath them, Sodium Vapor lamps cast an ambient light on the surrounding area, which — with two lines of working streetlamps — does wonders to illuminate not only roads, but much of the surrounding area. LEDs would brightly illuminate a skinny corridor, which isn't good for an open area. Having personally walked down sidewalks illuminated at night by Sodium Vapor lamps, I'm not too keen on the idea of walking in the middle an inky-black darkness, alongside a brightly-lit road with fast-moving traffic.
Thats not necessarily true. Properly designed streetlights do spread an even light. In fat it sodium lights that create harsh shadows.
Compare the shadows on this comparison page
http://www.recycletechno.com/led.htm
Heres one that shows them being mostly even
http://www.cityofboston.gov/publicworks/lighting/led.asp
Heres one last one
http://ledlightreviews.files.wordpress.com/2009/08/led-vs-hps-betaled1.jpg?w=460&h=179
The problem in Clovis is streetlights are way too far apart. The good news is newer streets seem to have them closer together. Larger streets anyway, not residential ones.
From my experience in Clovis, the LEDs are better
I didn't even know my comment would get actual approval. Sorry for the slow response. The first link is dead, btw.
Here's a picture of the exact opposite. It's the LED light that has the corona of light. You can see the tree with the HPS light while you can't with the LED.
http://lighting.com/wp-content/uploads/HPS-left-retrofit-to-LED-street-lighting1-280×210.jpg
There's nothing about LED streetlights that makes them inherently better able to spread or disperse light then HPS lighting. That's more a function of fixture optics, fixture placement as you mentioned, and inappropriate choices of light intensity.
The problem with Clovis's streetlights, or should I say PG&E's sodium streetlights, is that the overwhelming majority of them are the grossly inefficient and obsolete non-cut off light. Take a look at the lights in Clovis. You'll see that most of them look are this.
http://www.acuitybrandslighting.com/library/ael/images/family/roadway-327_med.jpg
Now the much rarer, in Clovis at least, cut-off cobra-head. It's is far more efficient light design then the non-cutoff. You can usually see these at newly re-fitted Fresno intersections.
http://www.acuitybrandslighting.com/library/ael/images/family/roadway%20series%20125%20cutoff_med.jpg
The disparity in light efficiency just between these two designs is so great that when switching to a cut-off light you must substantially reduce wattage. In this case the lights in the foreground are running at half the power then the lights in the background. Or to put it in other words, a 50% reduction in power use. It's essentially equivalent to switching to LEDs without any of the LED drawbacks mentioned later.
http://www.starlight-theatre.com/images/ROADWAY_GLARE.JPG
The reason for this being is that all the light that was going into the sky and your face is recycled and shot back to the ground. By not wasting light, less light needs to be generated by the fixture to do the job.
Clovis, or PG&E, should have upgraded their lights to cut-off instead of trying to get on the bandwagon to say, "we have LED streetlights," the reason being is that the blue-rich lights chosen have a depressive effect on melatonin production at night. Melatonin mediates our day/night sleep cycles, plays a role in our immune system, and suppresses breast cancer in women and prostate cancer in men. I'm afraid those LEDs are not better.
http://www.darksky.org/assets/documents/IDA-Blue-Rich-Light-White-Paper.pdf
Furthermore, blue-rich light is only advantageous at low light levels when our eyes are relying on Scotopic vision, think at night under the stars. At higher lighting levels,photopic vision, the light is more sensative to yellow-green, think at a brightly lit gas station or street. Sodium lighting is centered at around a 580 nm wavelength far closer then any of the blue-rich culprits. And yes, gold colored high pressure sodium is going to be better for the eye then blueish white LEDs or even metal halide.
http://physics.fau.edu/observatory/Images/photopic_sensitivity_sm.jpg
That's not to say LEDs can't be engineered to produce a warmer light. They can imitate any form of light even sodium., It's just that LED manufacturers are getting the greatest lumens to watt with blue-rich diodes,so that's what they market. If we press for better lights, the manufacturers will listen.
Good to hear about the closer lights. It seems PG&E is taking at least one step in the right direction.
Very interesting stuff!
Very. Here's something inspirational.
http://www.darksky.org/assets/documents/MMPG.pdf
I think the most impressive conversion were of the parking lot lights. Just converting those basically led to a energy savings in excess of $10,000 a year.
Some places that have good lighting near Clovis would be the California Eye Institute building. If you travel west on Herndon, just before the intersection of Chestnut, there should be some nice cut-off luminaries lighting the street. The intersection of Herndon and Armstrong should also have some ,relatively, nice cut-offs. If you're traveling west on Herndon, the light on the opposite corner won't even be visible until you enter the intersection.
I think both Clovis and Fresno should enact minimum light efficiency standards for light and glare produced. If they don't have it already. Clovis should enact a series of self-protection laws for its street lighting so PG&E can't exploit the city or its serving divisions with bad lighting choices.
I just had to share this. It seems as if the LED manufacturers are listening. These look promising.
http://unilumin-lighting.com/cont/Classical-Project-Case_96_200.html
http://www.lightfair.com/lightfair/V40/iAwards2011/images/lia11pic_LeotekGreenCobraLosAngeles.jpg
http://www.panoramio.com/photo/7046079
http://www.thepeterboroughexaminer.com/2013/06/04/led-street-lights-a-hit-clarke
As you can see all the lights,especially the last, lack that garish blue-tint characteristic of Clovis's lights because they have a color temperature of around 3,000 kelvin which is about the color of incandescent light while Clovis's lights are probably closer to 5,000 kelvin.. Here's something interesting. On the third page you can see how warm white light–3500 kelvin– compares with cool white light–around 5,000 kelvin. It's LED vs HPS Vs LED.
http://www.southamptontownny.gov/filestorage/596/598/4245/5194/IDA_Seeing_Blue_Nightscape.pdf
The last PDF reminds me of a trial Boston did. They set up 5 or 6 street lights with different LED bulbs and there was a public vote on them.
I think I remember reading an article on that. I don't think the article ever came to a conclusion though.
I've read of LED street lights that change color and light intensity throughout the night. They start at 4200 k at dusk, and when it reaches late night the intensity is stepped down as the light color temperature changes to 2700 k.
I found some Chinese LED street lights. They seem to be really interested with warm white LEDs.
http://www.panoramio.com/photo/7594749?tag=LED%20Street%20Lamp
Here's something also interesting. I know it's interior lighting but
http://www.gelighting.com/LightingWeb/br_en/projects/las-vegas-sands-corporation.jsp
I also wanted to share examples of bad lighting. Recently, ARCO gas stations have been upgrading their outdoor mecury roof lights to cut-off LEDs which are fairly good, but they've also taken a big step backwards by installing bad fluorescent tube floodlights in place of the excellent shoe box cut-off lights. This was likely done in response to the upcoming mecury lighting ban which will outlaw mecury lighting,but not interior fluorescent tube light, in a year. The gas station in question is at the corner of Blackstone and Bullard.
Clovis seems to be on a blue-rich LED lighting craze. They recently converted their main school bus depot at Herndon and Sunnyside from HPS to LED. Unfortunately, it seems they just switched the light source type. They still make extensive use of very inefficient LED flood lights which shoot light out at oncoming traffic. It goes to show that just being LED isn't necessarily a good thing. It also shows that they really aren't thinking out of the box.
I really want to give proposals to Clovis and Fresno, but I don't know where to start. You seem pretty familiar with this, where should I go to propose my ideas to the city?
Clovis is very responsive through their service request thing online.
http://www.ci.clovis.ca.us/Government/Customer-Service
You should be able to either ask who to speak to, and get connected with the right person, or make you comments directly.
Fresno is a little harder. Unsure how to find the right person. What complicates things are that PG&E owns or is responsible for many of them.
I'll give that link a try. I've used it before to report burnt out streetlights, and Clovis–or PG&E– seemed to fix the lights quickly.
PG&E defiantly makes matters a bit more complex. I've read of power companies supposedly using cities to help ballast their excess off peak power with inefficient choices of street lighting.
Does Fresno have public city council meetings? I'd assume if they did, then maybe it would be a good chance to actually share ideas with the city.
Yes the city council meets twice a week. I believe you can raise any issue of your choosing during the public comment section, but youd best ask the secretary or whoever to verify this to be sure. The city planning board meets weekly. You can also email city councilors directly. Ive tried the link on the website to email them and never heard back, but I emailed Lee Brand directly and he got back to me quickly.
News. I got a reply from the City of Clovis. Bad news, the email reply made no mention of efficiency standards for street lighting. It also made no mention of the city or PG&E analyzing alternatives such as more efficient sodium cut-off lighting.
"The City worked with PG&E to retrofit some of the City owned lights. PG&E recommended the selected lights based on the existing light lumens provided. We believe the LEDs are a superior alternative to the high pressure sodium lights as they provide a more daylight type light, are efficient and provide a very long life compared to the high pressure sodium."
A "more daylight type of light" is not what you want out of a street lighting system as it more readily suppresses the production melatonin,
Another big reason to avoid white LED street lighting is the substantially increased light pollution produced by Rayleigh scattering.
"the visibility of sky glow from blue-rich light sources on the ground is dramatically increased because this blue light, (is more so) preferentially scattered in the atmosphere,
http://www.illinoislighting.org/lightcolor.html
Which goes on to help explain why blue headlights and blue-rich white light sources are so annoying at night.
"Photons of shorter wavelengths carry more energy. Because of this, blue and ultraviolet light to create much more "wear and tear" damage to the cells in the retina of the eye than moderate or long wavelengths, leading to vision loss. Children's eyes are particularly susceptible to the phototoxic effects of shortwave light."
It sounds like the decision was not made with any research, which is a shame. I doubt the person who signed the order is a lighting expert. You could potentially take the next step and arrange a meeting to talk about your concerns and inform the person about your thoughts on the matter.
Also, I doubt anyone has ever asked if the existing lumens providing is the RIGHT amount of lumens. Many sidewalks are pitch black.
I tried asking in the email who to speak to about these concerns, but they never told me who. Do you think it would be wise to go to their civic center and ask in person?
I know what you mean about the under lit streets. Clovis and Fresno both use a standardized wattage of 70 for their non-cutoff sodium luminaries. This wattage is enough to sufficiently light a neighborhood to federally recommended standards, but the problem is that both cities don't adjust their light wattage higher to properly light bigger streets. Take this for example. The same 70 watt luminary that lights this street…
http://goo.gl/maps/veoEP
http://goo.gl/maps/NiNtG
…is also used to light this street.
http://goo.gl/maps/5nFda
http://goo.gl/maps/RQMkI
and if that didn't drive the point home far enough then this street…
http://goo.gl/maps/mWwXn
http://goo.gl/maps/U8tOV
There's actually no written regulation within Fresno's street lighting plans that ever list situations mandating the use of any power light higher then 70 watts.
http://www.fresno.gov/NR/rdonlyres/F689CA6C-E555-44B8-9D6E-2A1AB520A2E8/0/StreetlightplangeneralnotesApril2013.pdf
Intersections,however, are slightly better as they are standardized at 150~200 watts in Fresno and Clovis, and some are even cut-off which makes them about adequate for large streets.
Blackstone is the absolute worse.
Clovis is getting a little better, it looks like theyre requiring tighter spacing. Compare the left side of the street (late 90's?) to the right side (last year)
http://goo.gl/maps/RKF25
Of course theyre not pairing them with what may possibly be the worst lights ever made
http://goo.gl/maps/Xyp5G
How are there only a few of us that notice the cold sharp light , everyone just talks about efficiency , I’m in Ireland 🇮🇪 and there at the same crap
Mr. Independent, you sound like you are a very thorough person that has alot of knowledge in this topic…however I believe the people of Clovis made the judgement to change the lighting based on cost cutting measures and other factors, and the fact that people just are tired of that dull orange light that we've been seeing for far too long. I personally like the LED lights because they look "different" at night. Whether that means I'm trying to say "a more daylight type of light" then so be it. I like it, I feel like it's easier on the eyes and makes the street more visible. If they can turn up the intensity it would be all the more better. One of my biggest complaints is when I come back from a weekend in LA I REALLY notice how dark the streets are in Fresno..I mean..you can't even see a person standing at a crosswalk in this city…it's ridiculous and dangerous. But being LA is LA…they prolly get the latest and greates of stuff including streetlights…so…I don't know. But I appreciate your posts. Veery interesting, I read them all :).
I think Mr Independent is saying that with some tweaks, we can have the same energy saving and long lasting lights that do a better job – ie, better sidewalk illumination, less light pollution, and a color that both looks nice and works well for what our bodies need.
You should visit some cities on the east coast, they light up their streets like a stadium, you never feel unsafe walking.
I think I'm going to have to take your advice James. Maybe it's just me, but I'm all about adequate lighting. Gives a feeling of safety and makes you WANT to stay out till nightfall or simply go downtown or somewhere not less travelled. Another pet peave of mine is the lack of accent lighting on our buldings in Fresno. OMG go to Staples Center for an even there and they have the spotlights going and the building is all lit up on the outside and its lights camera action. You go to an even at Savemart and it's not even lit up. Sometimes the only way you know theres an even goin on is to see the parking lot semi full from the 168 hwy. It gets depressing. Accent lights to me give me a sense of civic pride. Just my opinion.
I told this to Clovis…
"I want to remind the city that the purpose of street lighting is to light streets. That cannot be properly achieved by assaulting the eye with harsh glary lighting cast in every direction. For good perspective compare the LED lights the city has chosen with the blue-rich lights in source 1.
http://i2.photobucket.com/albums/y17/jamesinclair/Fresno/IMG_3866.jpg
http://www.southamptontownny.gov/filestorage/596/598/4245/5194/IDA_Seeing_Blue_Nightscape.pdf
Glare reduction is a key component of a successful lighting system. Research done as early as 1955 indicates that blue rich white lighting causes more glare with later studies confirming a light wavelength of 420 nm to be most closely linked with discomfort glare. A light source with an spectral output below 500 nm will increase the perception of glare.(Source 1) Most white LEDs have peak emissions of around 460nm. (Source 2)
Blue rich light increases the time it takes for the eye to adapt to darkness or low level lighting. (Source 1) This trait is particularly detrimental to a growing city with a mix of un-developed and highly developed streets. The blue-rich LED street lighting light makes seeing one's surroundings more difficult then with light with lower spectral power output such as HPS. (Source 1)
There are better alternatives to the chosen LED streetlights available to the City of Clovis. Today LED manufacturers are perfecting warmer color lights that are almost indistinguishable from incandescent light.
http://www.thepeterboroughexaminer.com/2013/06/04/led-street-lights-a-hit-clarke
"”Coun. Henry Clarke took time during Monday night’s city council meeting to rave about the new LED street lights retrofitted on a select few streets in his ward as part of a pilot project.
“It’s like driving in moonlight,” he said. “It’s a soft, gentle, white light. You can see clearly. It is just so relaxing and it really enhances the neighbourhood.”
It should be noted that most residents in source 1 preferred the 'warm' white LEDs over the HPS lamp and the 'cool' LED light. I ask the city to realize the superiority of available alternatives to the chosen lights.
Sources
http://www.southamptontownny.gov/filestorage/596/598/4245/5194/IDA_Seeing_Blue_Nightscape.pdf
http://www.illinoislighting.org/lightcolor.html"
Here was their reply.
"Thanks, we will look into this when we do the next group of lights."
I used to live in Los Angeles County. There are some notable differences between Los Angeles and Fresno. One of the main differences,at least in Long Beach, is wattage. I'll give you an example. We'll use the brightly lit intersection of Redondo and 7th Street. Each intersection cut-off sodium light chugs down 250 watts each. This is easily determined by reading the NEMA wattage label via google earth.
http://goo.gl/maps/gyBaw
Now that brings me to another point, density. There are at least 6 lights at this single intersection.
http://goo.gl/maps/7T1jp
Now this intersection is with adjacent sidewalks around 77×99 feet big leaving an area of 6776 sq. ft.
Now lets go to the typical Fresno intersection. We'll use Herndon and First perhaps one of the largest and busiest intersections in all of Fresno. The lights are of the less efficient non-cutoff design, and each of the four lights runs at 200 watts each. Now the intersection is 168×129 feet. That gives an area of 21,672 sq. feet.
That means the Fresno intersection is three times larger and has to make do with a little over half the wattage the the Long Beach intersection all while using the inefficient fixtures,
Also, streets that Fresno would light with 70 watt lights, Long Beach lights with 150 watts or more. Typically 150 watt lights are reserved for highways and large intersections in Fresno. I don't want to justify a megawatt mentality. Their high energy use may be inappropriate especially if they upgrade fixture optics.
Street light fixtures with cut-off optics aren't particularly more expensive then their non-cutoff rivals. Have a look at the cut-off model…
http://www.kolmart.com/Cobra-Head-Light-70-Watt-Sodium-S62-4-Tap_p_680.html
Now the non-cutoff..
http://www.kolmart.com/Cobra-Head-Light-70-Watt-Sodium-S62-4-Tap_p_668.html
Wouldn't it be nice if we started installing better lights from now on?
Jeffrey, I agree, more accent lighting would be nice.
Independent, I actually used some of your lighting advice for a project Im working on.
I wish the lights attached to traffic signals had two ehads pointing at different crosswalks. Other cities outside California do that.
Hey Mr. Independent, thanks for all the info about streetlights. very informative. So is their any chance that Fresno/Clovis will either increase their wattage or increase the number of streetlights around intersections or???
Seeing as how Fresno currently goes about its street lighting, without a serious talk to, we may be stuck with inadequately lit streets. The city needs to be reminded that street lighting is for lighting streets and sidewalks. It should be a system that promotes ease of visibility and has the lowest amount of wear and tear on our eyes.
As I understand, adding lighting to built up areas such as intersections or interchanges on highways and streets can help to reduce fatalities. I may have to try and do some digging to find the original resource on that.
One of the big issues that can be pressed is how easily visible pedestrians are on the sidewalks and streets at night as well as any stray road debris for drivers. Another point to bring up is how easily pedestrians can see obstacles in their path which could be shown with photography comparing how visible people and things are with different light intensities. You could also use the photography for car traffic as well.
I'll try looking up recommended light lumen levels for streets and seeing what what's recommended, preferably federally.
On a side note, the casinos of Las Vegas both make extensive use of decorative lighting to great effect in public spaces. They certainly are able to put Fashion Fair to shame.
http://images.oyster.com/las-vegas/hotels/thehotel-at-mandalay-bay/photos/shops-the-hotel-v142872-800.jpg
http://images.oyster.com/las-vegas/hotels/thehotel-at-mandalay-bay/photos/restaurants-bars-the-hotel-v142995-800.jpg
http://images.oyster.com/las-vegas/hotels/thehotel-at-mandalay-bay/photos/front-desk-the-hotel-v142874-1600.jpg
http://0.tqn.com/d/govegas/1/0/x/L/thehotel0003.JPG
The public restrooms…
http://0.tqn.com/d/govegas/1/0/2/M/thehotel0009.JPG
Ah, the tandem head. I know it's Las Vegas….
http://goo.gl/maps/lSer2
The lights at their newer intersections, 2005 onward, actually have mounting points built into each one of them for additional lights if the city ever felt it appropriate to improve visibility through added, or further dispersed, light. First the light.
http://goo.gl/maps/CXSjk
Now the up-close of the empty mounting bracket.
http://goo.gl/maps/baaQL
On a side note, take notice of each pole's glean. I'm not certain,but the city may use poles with a heavier chrome coating for that extra bit of shine throughout the poles' lifespan. Another note in relation to accent lighting, each pole also uses back lit street names that could,possibly be used at notably larger streets.
I can think of several Fresno/Clovis intersections that would benefit almost immediately from the refit Clovis and Herndon comes right to mind. Of course that would mean the old lights would have to go, but we'd probably be better off in the long run.
There is another,possibly cheaper and easier, alternative to this for re-fitting existing intersections. It would be to replace the simple traffic signals with standard lights that mount traffic signals. Here's the current light.
http://goo.gl/maps/xamdL
and now the proposed light combo…
http://goo.gl/maps/UFDhS
Yes, a tandem light is exactly what I was talking about.
Youll notice some older intersections (like along Shaw) actually had lights in the median as well. They dont do that anymore.
Fresno St. after Sierra also has allot of tandems.
I found something interesting for accent lighting. The Saint Anthony Falls Bridge. It's a stunning bridge during the day and especially at night.
http://www.johnweeks.com/i35w/i35w_night.html
The lighting setup is impressive ,but it's pretty understandable and simple in ways. The guardrail has lights recessed into it which lights the decking that you can see in the 9th and 10th photos.
The lighting for the piers is recessed into the ground next to the piers. You can see a photo of it if you scroll down.
On a side note, I really like how they did the observation deck with the low light fixtures.
I like the bridge in gold.
http://www.johnweeks.com/i35w/i35w_gold.html
The Saint Anthony Falls Bridge shows that concrete pre-fab doesn't have to be as boring as Cal-trans makes it out to be.
I found something that might just help getting Fresno proper lighting. It's really good. It's a downloadable pdf if you follow the link.
http://www.techstreet.com/products/preview/739518
I like this," The purpose of roadway lighting is to provide quick, accurate, and comfortable visibility at night. These qualities may safeguard, facilitate, and encourage vehicular and pedestrian traffic…the proper use of roadway lighting as an operative tool provides economic and social benefits including.
(A) Reduction in night accidents, attendant human misery, and economic loss.
(B)Aid to police protection and enhanced sense of personal security…"
I think that book might be the ticket to Fresno's street lighting future. The book is ANSI approved while its authored by the IES, two very important nonprofit organizations.
I wanted to ask. Which intersection in Fresno do you think is most poorly lit with the street lights on?
Couldnt say off the top of my head…but many in the older parts of town – downtown, kings canyon corridor, and blackstone corridor. You know, the parts with most pedestrians.
Last time I went to Tacos Tijuana, the entire road was pitch dark.
Terrible spacing means if one light is out….a huge area is out.
I wanted to share some information on CCT, or Color Correlated Temperature. It's an important metric used by lighting designers to determine a light's color.
Imagine a bar of iron. If you heat it, it will begin to glow red. If you keep on heating it, it will start to turn orange then yellow.If you kept heating it, it would eventually turn white and finally blue. That is what CCT is all about. CCT uses the kelvin temperature scale to dictate light color.
http://www.rollitup.org/members/mrblixa-110951-albums-laboratory-picture830415-spectrum.gif
http://2bora.com/wp-content/uploads/kolor-swiatla-diod-LED-CW-WW-NWeng.jpg
The lower CCTs,such as 3000K, produce warm light while the higher CCTs, like 4500K, produce a cool light. High pressure sodium has a CCT of 2,200 K. Ideally, street lighting should not exceed 3000K.
Many do not know of CCT. It's a metric that is of great importance with LED street lighting because nearly every color temperature can be made with LEDs.
I have to agree with James on that one. Teerible spacing of streetlights along streets AND not enough streetlights around the interesctions. Either that or they just need to turn up the wattage or something because when Im driving along the streets, its lit so poorly that sometimes if theeir is a dead dogs or cat on the road I wont see it until I'm right up on it. Another thing I want to point out is where are the freeway streetlights on our freeways?? Particularly along 168 from bullard all the way to the 180 interchange?/ COMPLETLY darked out. I heard the news talkin about 41 from 180 south to 99 was shut down for the weeknd for "freeway maintenance". And I did notice the new LED freeway lights on the southern part of 41 extending to 99…those looked nice. But damn gotta light up our freeways this is ridiculous. Well, Im goin to be going to Las Vegas for the DOGS game, then off to NYC at the end of Jan. I'm sure THESE 2 cities will not have the problem of inadequate streetlighting.
Surprisingly, the street lights in most parts of Manhattan are terrible. However, the buildings put off so much light you barely notice.
Highway 168 appears to have the standard Caltrans light setup. That is 2~3 approach lights and 1~2 departure lights for on and off ramps respectively with freeway signage floodlighting. It's not necessarily a bad setup unless you have traffic continually merging in and out of each lane that requires special attention to detail.
Herndon ,by the way, has a 'freeway' type setup with approach and departure lights only. Except the wattage is too low because the lights are mounted too high up. That's another one of Fresno's street lighting problems in addition to poor spacing. Typically the only reason you'd use tall lights, ones with riser arms in particular, is to cover a greater areas, but when you increase fixture height you must increase wattage to maintain lighting levels which Fresno doesn't realise. The end result is a dark street even under the lights. Here's a pic of one of the notorious lights.
http://goo.gl/maps/Rvf2X
Las Vegas defiantly has an impressive setup on I 15. I suspect they CAD'ed it for extra light quality. They make use of huge 100+ foot tall light masts running on HPS. Light masts have fasicinted me for years.
http://www.aaroads.com/west/nevada215/i-215_ol_exit_007_01.jpg
Along with that, they also use floodlights angled towards the road acting like cut-off lights.
http://www.nevadadot.com/uploadedImages/NDOT/_Homepage/Express%20Lanes.JPG
As for Highway 41, the LEDs are Leoteks which have been there for a little while. They have a CCT of around 4500 K which is too high for public lighting. Cal trans is ahead of Fresno in certain respects namely in wattage and fixture type.
The caltrans setup again has redundancy problems, because they take forever to fix a broken light. I think the Herndon/Clovis 168 entrance was (has been?) completely off for months.
They really need more lights in the freeway mixing zones.
I know that interchange. It was one of the best lit sections of Herndon, I can't say for 168, until all, not just some, of the overpass lights went out. Those lights formed a great deal of that interchange's light. Several higher wattage cobras also went out. Also,to compound matters, Clovis doesn't maintain lights of near matching type or wattage, so the light intensity falls sharply of as soon as you pass the highway/street intersections. The 168 and Fowler interchange still has lights that are working, and Fowler is very well lit as it crosses over the highway. Nearly any lighting system can be brought to its knees without regular preventative maintenance, and dark spots are inevitable with burn outs unless you light and re-light the same area. That being said, the only setup I've witnessed shrug off burn outs with relative impunity has been the Las Vegas Boulevard system, but they pump in hundreds of watts a light, and they use many tandems and mirror lights in addition to the ambient light. I finally found out they use 400 watt cut off HPS tandems at their intersections. That sort of engineering would allow a fair degree of systematic redundancy.
http://goo.gl/maps/rsQrr
Now if you're talking about lighting on the freeways with the two approach one departure light, that's a different story.
It is a public safety issue. I believe Mr.Sinclair wrote of several accidents occurring at night on poorly lit streets or streets in which the driver couldn't see. One accident happened on a under-lit street albeit some time ago, but still, all the more reason something like that shouldn't have happened again let alone in school zone which ,as you're about to see did.
http://stopandmove.blogspot.com/2011/10/teenage-student-hit-by-car-guess-who.html
"Last Thursday, a teenage girl was hit by a car at 6:30am while walking to her local bus stop…Police are still trying to piece together what happened. They said incident happened just before sunrise and witnesses say the road was dark which may have contributed to the crash.
Holland said the street was dark and the driver may not have seen the girl crossing the road. He said thieves recently stripped the street lights of copper wire and several of the bulbs were out at the time of the accident."
This accident was several years later on a ,similarly under lit and unfinished street, and next to a school in which a child was killed at night.
http://stopandmove.blogspot.com/2013/01/an-exercise-in-blaming-victim.html
"Many of the pedestrian victims wore dark clothing and walked on the roadway at night, said Sgt. Richard Tucker, of the traffic bureau. Tiani Philpot was wearing dark clothing and walking south in the southbound slow lane of four-lane Marks Avenue, near Emerson Avenue, when she was hit about 11:30 p.m….Fresno Police are working to determine who was at fault and whether the lack of lighting contributed to the crash"
I think whenever the police excuse a collision due to "poor lighting" a lawsuit should immediately be served at city hall for poor lighting leading to a death.
I really need to get the book that I mentioned by IES on street lighting. It delves into all the numbers for streets, crosswalks, and intersections. I've already tried looking at the library, they don't have it. It's too specialized according to them.
I don't know why the people of Fresno aren't complaining about this…whole streets are darkend out? Gosh dam. It's a public safety issue. Not to mention it's just not inviting for people to be waslking and exploring the city. I went dwntwn a couple Thursdays ago for arthop, it was totally cool. I havent been in about a yr but gosh the city was difficult to navigate. Other cities are inviting to peds with large/wide sidewalks, brightly lit streets, AND adequate signage. There's inadequate signage around dwntwn. We need to put those huge navigation signs that say "Fresno Memorial Hall–>" or "FederalCourthouse <–" "Chinatown–>". You know what I mean???
Many cities have invested good amounts of money on pedestrian wayfinding. Philly has fantastic signs.
Continued from the crosswalks links… In case you're curious to see how Los Angeles lights their crosswalks next to their schools, have a look.
http://goo.gl/maps/yuDFA
http://goo.gl/maps/Qmp2B
As you can see the high density of lights, at least 3 next to the crosswalk, ensures that if one light goes out the entire crosswalk isn't dark. Here's another for a, I'd assume, an unmarked crosswalk.
http://goo.gl/maps/tdwvX
http://goo.gl/maps/d2Fgh
and, at 200 watts a piece, they're high powered to. A fun little fact, 200 watt lights according to Fresno's standards are only reserved for the safety lights on the extra special 'super arterial and expressway' roads. Also have a look at the pole spacing, only 46 feet between the two lights–across the street. The Fresno 'standards don't specify special light applications for school zones or crossings, at all, but we'll use what the city calls a 'collector' street for extra tight pole spacing even thought it's probably a 'local' street with much greater allowed pole spacing. The spacing Fresno calls for is 150 ft. It's pretty important as Fresno doesn't mandate lights on for both sides of the street. So, if you're lucky enough to get an actual light next to the crosswalk, the nearest light is 150 feet away.
http://www.fresno.gov/NR/rdonlyres/AB8681EB-4508-425B-BBEE-71914E68798F/0/CHECKLIST.pdf
Here's another school crosswalk this time on an actual highway not one of those 'foe' expressways Fresno loves. Have a look at how Los Angeles builds a crosswalk on a high speed arterial with maximum safety equipment. Note the warning pavement markings placed well before the intersection.
http://goo.gl/maps/Yve49
The warning lights with the flashing yellows. Take note of the central median as well..
http://goo.gl/maps/F5cr0which
http://goo.gl/maps/F5YA9
The crossing lights are shown inactive, but they are activated by the buttons shown here.
http://goo.gl/maps/oBDwI
Take note of the tight pole spacing. There's a light on either side of the street that each carry a brilliant retro-reflective signs that are easily visible at night behind car headlights or the street light.
http://goo.gl/maps/AS99A
The lights, in case you're wondering, are 250 watt HPS models. I reiterate 200 watts of HPS is the greatest for Fresno in the form of ' traffic signal intersection lights.' It should be noted that it's not necessarily wattage that's really holding Fresno regulations back, it's that lack of mandate for lighting crosswalks of any kind.
Its shocking that crosswalks arent required to be illuminated. Many cities require x lumens at center of crosswalk.
The intersection of Ashlan and Blackstone looks promising while Blackstone and Dakota also looks promising. The reason why I ask is because I want to design a proposal for the city of Fresno that would upgrade the lights to full cut-off optics running at the appropriate wattage. Ideally, I'd like to see the poles replaced with entirely new constructions built from the ground up, but I'd like to consult with the IES guide to find the best lighting solution. Which do you think would be the better candidate?
I'll probably recommend cut-off high pressure sodium lights, but I might recommend a special LED test site. The reason why I mentioned CCT earlier is because I have reason to believe that warm white LED streetlights hold a great deal of promise, and I believe that a high traffic intersection may be a good location for attention for the lights.
I think leds have a lot of fed and state incentives which mean youd have better luck than sodium.
Do you know which federal incentives are available to Fresno? I know there's the Clinton Climate Initiative that Los Angeles used to get their lights. I could try them. I've really only found 1 LED cobra that meets nearly all requirements, but it looks expensive. The warm colour makes the cost even higher. I found one other, but it isn't IES verified.
http://lightpolesplus.com/141w-led-26-cobrahead-street-light-400-525w-hid-replace/
Basically $1,000 a light. Multiplied by 8 makes for a total of $8,000 just for lights just for one intersection. I'll get the price on the standard M400 to see the cost difference.
News from the City of Fresno on street lighting. It sounds like something's being done..
"City of Fresno officials today said staffing for streetlight repairs will be doubled beginning Monday, July 29, and estimated that most of the City’s streetlights should be repaired by the end of the year…Crews will be sent to areas in teams to address all lighting repairs at once, and two electricians will be assigned as a strike team to handle other urgent assignments…"
http://www.fresno.gov/News/PressReleases/2013/double.htm
But it's not really going to help much if the lights are glary,poorly spaced out, and have improper fixture heights.
Yes many lights were repaired this year….supposedly. I still see many lights out all over the place.
I had an experience of another kind at night. I was travelling down Highway 180 and eventually happened upon this intersection.
http://goo.gl/maps/YVSBz
Now, I know it's a more sordid highway of sorts ,but follow me. I was travelling west, and out of the dark arose the warm glow of sodium in the distance. A brilliantly lit warning sign signaled the approach of the intersection.
http://goo.gl/maps/qzFth
The smooth flawless concrete gave way to what was; an intersection free of glare and the painful retina searing metal halide parking lights characteristic of Fresno shopping centers.It was beautiful in ways. Visibility was clear and effortless. The oncoming glare of car headlights seemed to be washed out in the brilliant light of the intersection. Light levels appeared to be sustained throughout. It was awe inspiring.
http://goo.gl/maps/1guf3
http://goo.gl/maps/3xqXB
The lights,for reference, are all General Electric M400 full cut-offs. The 'median' lights are 200 watt models while the lights at the far outer corners are 310 watt models.
I am disappointed in ways. I want that sort of lighting for Fresno and Clovis, and seeing all those assets and capabilities used on something that few will benefit from compared to something like Shaw or Blackstone is disappointing.
I have also been impressed by those ntersections
I found something from the Federal Highway Administration on crosswalk lighting.
http://www.fhwa.dot.gov/publications/research/safety/08053/
Let's go into what the report means for crosswalks. You can see the recommended crosswalk layout as to having two fixtures one on either side of the street before the crosswalk. This is done for several reasons one of them being the maintenance of crosswalk illuminace levels, basically how much lighting is falling onto the crosswalk. As a result, two lights are necessary when lighting crosswalks on wider roads, essentially anything wider then two lanes of travel, or in their words,"This, the single 250 watt HPS light, may be acceptable for a two-lane road without shoulders or a median but inadequate for wider facilities.
The other reason two lights are needed is that you need to illuminate the pedestrian's vertical component with horizontal light, Think for a minute, if you were driving and all the light from a streetlight was coming straight down onto a pedestrian all you would be able to see might be a faint outline of his shoulders and the crosswalk because all the light is going to the top of his head and shoulders. But now imagine streetlight light that shines light outwards and not just straight down. Imagine that outward shining light just before the crosswalk. What you're now doing is shining light on the pedestrian's vertical component, his torso, his face, his arms,etc. He now becomes much more visible for one direction of travel.
By the way, the book from the IES on street lighting is on its way; so ,hopefully, I can go into greater detail for non-crosswalk lighting.
I like the fact that Cal Trans used two lights to illuminate crosswalks on the wider portions of road. Light levels are better maintained, and there's a degree of systematic redundancy that could benefit Fresno.
By the way, I found standards Flagstaff Arizona uses to determine when an intersection receives a mirror light on the other side of the street.
http://www.codepublishing.com/az/flagstaff/mobile/index.pl?pg=Flagstaff13/Flagstaff1312003.html
"At a minimum, four streetlights shall be installed, one on each corner of the intersection. For every leg of an intersection where the width of the leg is greater than or equal to eighty feet, measured at the curb returns, an additional streetlight will be installed."
So, if we were to follow Flagstaff's standards, nearly all of Shaw would have intersections with opposite mirror lights.
I've got the book on streetlighting, and I've ran the numbers. Here's what I got. The sample street was Blackstone Ave. All the lights are 70 watt hps models. with a total flux output of 6370 lumins. This is where it gets odd. The lughts on the northbound side sude of the street before Nees are shorter then the ones on the other side of the street, so we'll take the taller lights. They have a fixture mounting height of 35 feet.
So we now use the inverse square law, which is output divided by the square of the mounting height, and we get a total light intensity of 5.2 lux. That's a ballpark figure of what to expect. We'll give Fresno the benefit of the doubt and assume a best case scenario.We'll call Blackstone an arterial street with a low frequency of pedestrian conflicts, basically fewer the ten pedestrians on the street for the first hour of darkness…
Fewer then 10 pedestrians on Blackstone during the first hour of darkness? Certainly not in the winter. You see 10+ at one bus stop alone. Stand at any corner and youll count 30+ people crossing during an hour.
And on top of that, more people would walk if it felt safer (ie, if there were better lights).
Assuming Blackstone is an arterial roadway with a medium frequency of pedestrian conflicts, between 10~100 pedestrians the during the first hour of darkness, we should be able to meet the National Standards with 11~13 lux. If we drop the fixture height of the aforementioned 100 watt hps light down to 28 feet, we should have a luminous intensity of just over 11 lux.To help preserve uniformity, pole spacing may have to be dropped by around 10 feet.
Which corner? Shaw and Blackstone?
This best casr scenario dicatates the street receive 9 lux, and if there are more then just ten people that first hour, it's 13 lux.
The ideal light I currently feel would adequately light Blackstone throughout, with yet to take a headcount, would be a 100 watt full cutoff hps light with a total flux of 9100 lumens mounted on a 30 foot pole.That setup should allow an intensity of 10.1 lux at the street. The spacing between each light I have yet to exactly determine, but expect something along the lines of 120 feet between each light.
The other option is to go with a light of increased output.I'm a but reluctant to do so as the next light up is a 150 watt hps cobrahead. Assuming we have the same luminous efficacy of 91 lumins to the watt, we should have a high output of 13,650 lumins. To give you an idea if how much light that is, the.typical house light puts off around 450 lumins. Now back to the street. We can use an increased fixture mounting height of 32 feet to acheive 13.3 lux. Of course the pole spacing will also be increased to around 130 feet between each light.
By the way, I've contacted the city of Fresno to see if something can be done about the lights.
Excellent, please post any response you get
Well I contacted the City of Fresno.I called their street lighting and traffic signal department. Bad news, no one, not even the department head, knew much anything about their new led streetlights. They didn't even know who made them. No one seemed to understand much anything related to street lighting. They didn't even know what the inverse square law was despite that being one of the most primative foundations of lighting. They directed me to their engineering department because they, apparently, don't understand much about street lighting.
Considering the City Manager was also head of DOT, it doesnt surprise me. FResno acts like a city of 10k.
Why am I NOT surprised about the results?? Sheesh. This city has a long way to go to switch to LED and ot turn up the wattage or something to mKe the streets brighter. As I said bfore, they still need to light up the local freeways bcuz theyre ridiculously dark.
They spent $55 million on the braided ramps project, which I think could have been delayed 10+ years with a temporary fix of good lighting. The real problem was rush hour merging in the winter when it was dark at 4:30 and the headlights make it very hard to read speeds and distance.
Really interested in which LED manufacturers are providing and promoting CCT 2200 – 2700K.
That would depend on the type of LED, household or municiple use. Muncipality wise, LED manufacturers were getting more lumins to the watt with higher color temps, 5,000k, so that's what they more aggressively marketed. The big names,Cree,GE, and Leotek, all offer 3000k cobraheads with slightly lower light lumin outputs then their *new* blue rich, not older,counterparts, but they don't market the warmer colors as much because most of the general public doesn't really know about them.
Btw, I went to Oakland after their LED refit, and the streets looked really cold and stark even with the 4000k+ GE LED street lights.
"To Independent"
Mr. Sinclair suggested I contact you, I need some expert advise about my situation. Do you have any info about southside Herndon Ave from Millbrook to Cedar ave.
I was hit by a car "hit and run" in 2013 walking from Saint Agnes out the ER across parking lot walked right on the frontage road then right onto Herndon ave where the sidewalk continued past a bunch bench then the sidewalk seemed to me to have overgrown ants which pushed me to the street. It was 1:00am VERY dark and there were NO cars. I walked up against the curb when the sidewalk seemed to continue with trees overgrown hanging into street and overgrown bushes. I continued on the sidewalk when the trees and bushes pushed me back out to the street when i heard a speeding car, looked over my right shoulder saw the headlights. I jumped to my left into the street to avoid being hit head on and he car hit my right foot crushing it throwing my up them my shoulder hit the window on the way down.
I can tell you more privately but I'm looking for some experts like yourself to help me with the safety issues. ie. Lighting, lack of sign or bars prohibiting pedestrian access, why the traffic cams failed to provide video although there are at least 5 cameras, the overgrown landscaping which incidentally just last week they removed all the plants and trees.
ANYONE who has any insight on these areas I would greatly appreciate your comments or assistance. Thank you Mr. Sinclair for this blog and your help with the situation……..
To the Independent- Mr. Sinclair suggested I contact you regarding a private matter. Please contact me asap at rtbriskin@gmail.com.
Thank you sir! Richard T. Briskin
The closest things I could find as specification deficiencies at Herndon and Millbrook would be curbs jutting into the crosswalk at the intersection and doglegs at several of the crossing points.
As for the lighting issue,about the closest thing I can find at the moment, I believe there should be a 'crosswalk' where Millbrook meets the frontage road. That crosswalk *could've* been lit with two high powered 250 watt HPS lights if the city had decided it wanted to follow the FHWA's report. See fig. 11.
http://www.fhwa.dot.gov/publications/research/safety/08053/
One could potentially argue that background luminance, light, from glary excessively bright parking lot fixtures forced and adaptation level on the driver that caused debilitating glare that was beyond the masking capabilities of the street lighting system.
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