COM 0038.000 2010-2012 - Laserfiche WebLink

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Outdoor Lighting December 10, 2010 Page 2 of 3 The first testing of LEDs occurred about two years ago at the intersection of Kamehameha Highway /Manono /Lihiwai in Hilo with the installation of four cool LED lights that the Traffic Division purchased for testing purposes. The location was coordinated with the State DOT Regional office because of the vertical curve at the bridge which increased the competition of the LPS yellow light and the yellow caution light of the traffic signal and the extreme rainy conditions. The energy savings of the test measured at 72% which was good, however, the light levels were too low for the Traffic Division, the spectrum was too blue for the Institute for Astronomy, and the manufacture did not follow through with promised product development. The conclusions of this test was to look for warmer lights between the 3,000 Kelvin(K) to 4,000K temperature range. It was also decided not to purchase additional lights for testing. Several manufactures contacted us to look at their product, especially after we were awarded a $500,000 ARRA stimulus grant for LEDs that was published nationwide. All future testing was conducted by accepting produce lines that were provided to the County at no cost. The LED manufactures /providers informed us that they could not obtain reasonable energy savings in the LEDs with the color temperature below 3500K. The Institute for Astronomy was not pleased with the amount of blue light that was coming from the LED's that were above the 3000K range. Hence, we were faced with a dilemma without a solution. Meanwhile the LED industry began publishing many light units that were advertised as Dark Sky compliant and confusion reigned. Further investigation showed that on the main land the Dark Sky compliant rating was being used to indicate a fully cut off fixture only and had nothing to do with the Kelvin temperature rating that concerned the Institute for Astronomy. The International Dark -Sky Association published a brochure - Nightscape - issue #80/2010 in early 2010 wherein they recommended five points: 1. Always choose fully shielded fixtures 2. Use "warm- white" or filtered LEDs (CCT lower than about 3,000K to minimize blue emission. 3. Look for products with dimming capabilities 4. Work with utility companies for establishing a reduced rate for dimmed or turning off lights at late hours. 5. Consider the longevity of the entire fixture. The Traffic Division started looking at the possibility of using filters with the LEDs because the LEDs themselves were not producing the lighting spectrum that was satisfactory to our Traffic Division nor the Institute for Astronomy. The end result was a LED product that used a filter that reduced the harmful blue light and only allowed 1% to 2% in the range of 400 to 500 nanometers (nm) but was also in the higher range of the Kelvin temperature which provided the better energy efficiency. Fourteen LED were installed at the intersection of Kamehameha /Manono /Lihiwai earlier this year. The test has been very favorable and test results are showing a 50%+ energy savings. County of Hawai'I is an Equal Opportunity Provider and Employer.