Major improvements have been made to LED lights recently and also several studies have been done on the proper LED lights for street lighting. Attached to this memo is the memo from Joe Adams, SPU Engineering Manager with an attachment analysis from Christian Fenstermacher on residential LED’s. From both staff's investigation along with Ken Taillon, SEH Lighting Consultant, the attached revised policy was developed.

The major changes to the policy are as follows:

• Plan approval of lights and lighting standard changes to be done by SPUC Utility Manager and the City’s Engineer.

• Remove specific technical requirements of LED’s and allow for changes to be made by Utility Manager and City Engineer as technical advances are made.
• Commercial & Industrial and Arterial streets, recommendation is for a 4000 K LED.
• Residential streets, the recommendation is for either a 4000 K or 3000 K LED standard to allow flexibility.

Discussion recently on LED lights is the amount of blue light emitted and potentially a concern by the American Medical Association (AMA). Their recommendation is to encourage the minimizing and controlling blue-rich lighting to the lowest level possible to reduce glare and to minimize human and environmental effects.

It should be noted that even high pressure sodium lights emit a percentage of blue light. Attached is a table from the US Department of Energy on % of blue light in various light sources.

The 3000 Kelvin LED and 4000 Kelvin LED are the lights being considered. The 4000 Kelvin LED's do emit by a small percentage more blue light, however, they also provide more seeable light to the roadway surfaces than 3000 Kelvin LED's.

Both fixtures use essentially the same amount of power and are about the same cost. 

For collector streets, commercial and industrial areas, the 4000 Kelvin LED light would be the standard.  Recent LED

lights have been 4000 Kelvin LEDs on recent street reconstruction projects and developments.  Staff did installed a 4000 K and 3000 K light in the Prairie Meadow development to show the difference.  The residential lighting analysis from SPU staff does show the test case on these lights and also assisted in making the recommendation for residential lights.  One other fact that is important to note is that the LED lights being recommended will have more light than the current HPS lights.

Staff has attached recent information from a Cree webinar and the US Department of Energy on Street Lighting & Blue Light.

The budget impact on the revised policy to the city is none at this time.  Future revisions to light standards as improvements are done can be more cost effective to the city and the utility.