Moonlight & LED CCT analysis from Benya Burnett Consultancy, Davis CA.
“After the city staff reviewed available options, it was determined that the 4,000K CCT color temperature and the perceived increased brightness of fixtures were the primary causes of the negative public reaction. Several remedial actions were considered, but ultimately in October 2014, the decision was made to replace 650 of the already installed fixtures in residential areas and all remaining LED fixtures with Leotek 19-watt Green Cobra Jr., producing approximately 1800 lumen at 2700 Kelvin (soft-white). In addition, the installation would increase the number of house-side shields to reduce glare and light trespass” Davis, California article hereby Volt.org - more LED RetroFit Streetlights.
LED Streetlight Retrofit…
This spectrum analysis shows the comparison of the natural moonlight and LED at 4000 Kelvin. The blue spike makes LED unique and problematic. Blue is daytime for your body and health issues are now being connected to blue lighting from LED streetlights, cell phones, computers, and televisions. Apps can be used to ‘filter blue’ out at nighttime on your cell phone(s).GLARE and REFLECTION of bright outdoor lighting are unintended consequences which start in brochures and end up hurting our outdoor, nighttime, environment. High Kelvin numbers - above 3000K, create a light source that is like daylight for people and wildlife. These make it hard to see into the nighttime and when one all night are ‘blinding’. Blue spike can be reduced with 2700-3000K LED streetlight models. These ‘soft-white’ 2700 Kelvin LED fixtures often reduce glare and allow better night vision for pedestrians and bicycles. Soft-white LED can be found for your home too and are often 2700 Kelvin.Many cities are now picking streetlights below 3000K. Soft-white and dimmer LED models allow good vision at night while providing even better energy savings.
Click here to see City of Phoenix LED street and park lighting rated at 2700 Kelvin.
Edison light bulb was developed after many tests.The incandescent bulbs are at about 2600 Kelvin and the meter shows the visible spectrum that works very well in our eyes.
Comparison of three LED (light emitting diode) light fixtures.
Click on these to enlarge each one.
Department of Energy2013 Research on pedestrian lighting needs and better LED lighting approaches - here.
Understanding Quality of Light!
International Dark Sky Association with three decades of experience, great resources, and experts that help with accurate evaluations. Our friends in Tucson were a GREAT help to Phoenicians in leading the world to better 2700K LED street and park lighting! More here.
Options for LED for your home…We can all benefit from LED lighting. In our homes, ‘soft-white’ bulbs are typically rated at 2700 Kelvin. Check on back of case before you buy new lighting for your home or business. See Cree LED example below - right. Good news includes more energy efficient and LED are not very hot. Special dimmers are necessary but they save more energy then old ‘watt’ dimmers.EXCELLENT outline of TERMS & TIPS from experts on LED lighting and the evolving technology; click here for pdf with more links.
Cree LED 2700K is a ‘soft-white’ light bulb for your home. The visible spectrum here is similar to the Cree street lights used in Phoenix.
June 2016AMA - BLUE LIGHT SERIOUS HEALTH CONCERNS
AMA Compete Guidance to reduce health issues from high intensity lighting - here.
BLUE SPIKE from some LED streetlights, cell phones, computers, and TV’s, can negatively affect your health according to American Medical Association. AMA Press Release - LED Health Concerns - Light Pollution problems here.
AZ Doctor raised new LED streetlights & health issues with City of Phoenix on TV Channels 3 and 5. Read problem and solution here.