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Home My WebLink AboutCOM 0038.003 2010-2012TO: Dominic Yagong Chair, Hawaii County Council FROM: Dan A. Cole RE: LED Streetlights Aloha Dominic. 21 January 2011 I happened to be in the Council room when Traffic Division Chief Ron Thiel gave his testimony before the Council about the technical requirements and other information relating to LED Streetlights. I was also outside the Council room during a portion of the conversation between Ron Thiel and astronomer Richard Wainscoat. It appears that Chief Ron Thiel doesn't understand the actual application of the astronomer's technical requirements of the light spectrum output of outdoor lighting to comply with Dark Sky's requirements, and by the apparent resistance of Mr. Thiel to attempt to understand the technical light spectrum requirements that Dr. Wainscoat is presenting it might appear that a deal may already have been made, officially or unofficially, to procure LED Streetlights regardless of technical spectrum requirements. As you can see by the attached documentation I have been working in the areas of LED systems for a while now and I believe that due to current manufacturing technologies LED Streetlights can be produced that meet both the County's and the astronomers requirements. I believe that if the County and the astronomical community updated their understanding of current LED technologies they would soon agree on a design that would be acceptable to both. Thank you for your attention in this matter. Alo a, go A Dan A. Cole Comm. NU Ref. To. ft� wa L' ou.tte„', Ref. Date FEB 2 2011 Print Page 1 of 1 From: Richard Wainscoat (rjw @IfA.Hawaii.Edu) To: cole_hawaii@yahoo.com; Date: Mon, June 1, 2009 12:43:16 PM Cc: Subject: spectrum of orange LED and low- pressure sodium lamp Hi Dan: It looks like the LEDs you sent do not conform to the spectrum shown in the spec sheet. The spectrum has a broad peak around 600 nm (orange). They emit light roughly from 570 nm (yellow) to 625 nm (red). To the eye, the color doesn't look a lot different from low- pressure sodium, because mixing yellow and red cannot be distinguished by the human eye from pure orange light. The attached PDF file shows a spectrum of an LPS lamp (sharp peak near 590 nm), and the orange LED that you sent. The total amount of light is held constant - so you can see how much sharper the LPS emission is compared to the LED. It is possible that the spectrum of the LED shifts a little with temperature. The setup you sent is probably not ideal in terms of thermal management - I don't know whether that contributes to the redward shift. Also, if you are not driving them with the correct current/voltage, this could also produce a spectral shift. The broadness of the LED emission is comparable to high - pressure sodium lamps (HPS). However, high pressure sodium has a blue -green and a yellow sodium emission line that adds some bluer colors. Aloha, Richard Wainscoat http: / /us.mg2.mail.yahoo.com/dc /launch ?.rand= ffb83avtatp6b 1/21/2011 Intensity I -.l 0 0 O 0 0 0 r U) D- 0 CID r m 0 C cn CD CQ 3 0 0 I I Print Page 1 of 1 From: Dan Cole (cole_hawaii @yahoo.com) To: rjw @IfA.Hawaii.Edu; Date: Mon, June 1, 2009 1:26:54 PM Cc: Subject: Re: spectrum of orange LED and low - pressure sodium lamp Aloha Richard, Thanks for the information, I will check with the manufacturer on their specifications. I have some LM317voltage regulators on order for another project so I will see if they make a difference in the spectrum, Thanks again for your help. Aloha, Dan From: Richard Wainscoat < dw@IfA. Hawaii. Edu > To: cole_hawaii @yahoo.com Sent: Monday, June 1, 2009 12:43:16 PM Subject: spectrum of orange LED and low- pressure sodium lamp Hi Dan: It looks like the LEDs you sent do not conform to the spectrum shown in the spec sheet. The spectrum has a broad peak around 600 nm (orange). They emit light roughly from 570 nm (yellow) to 625 nm (red). To the eye, the color doesn't look a lot different from low- pressure sodium, because mixing yellow and red cannot be distinguished by the human eye from pure orange light. The attached PDF file shows a spectrum of an LIPS lamp (sharp peak near 590 nm), and the orange LED that you sent. The total amount of light is held constant - so you can see how much sharper the LPS emission is compared to the LED. It is possible that the spectrum of the LED shifts a little with temperature. The setup you sent is probably not ideal in terms of thermal management - I don't know whether that contributes to the redward shift. Also, if you are not driving them with the correct currenVvoltage, this could also produce a spectral shift. The broadness of the LED emission is comparable to high - pressure sodium lamps (HPS). However, high pressure sodium has a blue -green and a yellow sodium emission line that adds some bluer colors. Aloha, Richard Wainscoat http: / /us.mg2. mail. yahoo. com /dc /launch ?.rand= ffb83avtatp6b 1/21/2011 Print Page 2 of 3 - - -- Forwarded Message - - -- From: Dan Cole <cole hawaii @yahoo.com> To: Brian Yuan <brianyuan @vitoindustrial.com> Sent. Mon, April 20, 2009 5 :43:03 PM . Subject: Re: Yellow 588 nm wave legnth LED Aloha Brian, I am sure the lower power LED Road Lites, 28W - 35W may work for my application, they would be solar powered, probibly 12 VDC. I am currently working with the Observatories Support Services to find a task specific lighting for areas near the Mauna Kea Observatories that would comply with the Dark Skys regulations enforced here on the Island of Hawaii that could be powered by solar panel /battery storage due to the expense of runing AC power to remote areas to provide safety lighting for the general public. I have a prototype in for testing to insure that LED spectrum light can be filtered out. If the LED design is type excepted then I would expect to move forward in looking at what types or area lighting would be required. Would you have a ballpark estimate on pricing and shipping of 28W -35W 588nm Road Lites? Aloha, Dan Cole From: Brian Yuan <brianyuan@vitoindustrial.com> To: cola hawaii@yahoo.com Sent: Monday, April 20, 2009 5:16:22 PM Subject: Yellow 588 nm wave legnth LED Dear Mr. Dan Cole, Thanks for your enquiry from the made -in -china about our 240W High Power LED Road Light (VT108SP- 240H), this is Mr.Brian from VITO to respond your emails. 1 understand your requirements of the Yellow 588 nm wave legnth LED is to generate some kind of Amber light, this color light is used a lot due to the telescope observatories on Maui and Hawaii islands, it reduces the glare in the atmosphere. We can use such kind of LED in our light system, but it is small power LED rather than high power LED, because at present no supplier can provide us such color high power LED chips, however, the small power LED's lighting efficiency is more lower than the high power one, and most of our models in such type are 28W or 35W, not exceed 56W, so if you demand the 240W, I don't think we can supply them. In addition, you mentioned the light system of 24 VDC, then may I ask if it is used in the solar light system? if so, I also suggest the LED lamp power not exceed 56W, otherwise it will be not stable. htti)://us.mp-2.mail.vahoo.com/dc/launch?.rand 1 X1) 1 / 1 Print From: Brian Yuan (brianyuan@vitoindustrial.com) To: cole_hawaii @yahoo.com; Date: Mon, April 20, 2009 8:32:04 PM Cc: Subject: Re: [SPAM] Re: Re[2]: Yellow 588 nm wave legnth LED Dear Dan, I think the range of your mentioned LEDs belonges to the infrared light, we don't deal with such kind of products, but I suggest you search PLANT GROWING LIGHT or LED INFRARED LIGHT, there are many suppliers in this business. Best regards, Brian On Tue, 21 Apr 2009 12:24:37 +0800 (CST) Dan Cole < cole_hawaii(t� ,yahoo.com wrote: Pagel of 3 > Aloha Brian, > Thank you for the information about your products. I will inform you of the results of the optical testing and acceptance test for the 588nm devices. > I am also working on a project with some of the medical doctors here on human cell growth for healing of wounds in diabetics and skin disorders that appear to benifit from the wavelegnths of 660, 680, 730, and 880 nm of 4,000 - 6,000 mcl. Do you know of a source of 5mm LED's in thoes wavelegnths? > Thanks again > Dan > From: Brian Yuan < brianyuan dvitoindustrial.com > To: Dan Cole < cole hawaii@yahoo.com > Sent: Monday, April 20, 2009 6:10:42 PM > Subject: Re[2]: Yellow 588 nm wave legnth LED > Dear Dan, > Thanks for your information, after study your application, I think if > your project is not along with the urban street, we can supply a good > choice of solar pathway light for you, it is a good product to use the > sun energy to light up the pathway, sidewalks, park station, bus station, http: / /us.mg2. mail. yahoo. com /dc /launch ?.rand= ffb83avtatp6b 1/21/2011