I write in response to Monday’s guest column (“Fight glare from new city lights”) that raised serious doubts about the health and environmental safety of the city of Northampton’s plan to replace its high-pressure sodium (HPS) streetlights with new energy-efficient light-emitting diode (LED) streetlights.
Specifically, the column asserted that the city is ignoring the expert recommendations of the American Medical Association and the International Dark-Sky Association. In point of fact, the LED streetlights Northampton is installing meet or exceed the recommendations of both organizations.
In June, the American Medical Association issued guidance for communities on selecting among LED lighting options to minimize potential harmful human and environmental effects. This widely publicized AMA report made three recommendations: It supported community-based conversion to LED lighting to reduce energy consumption and decrease fossil fuel use. It encouraged using the lowest emission of blue light possible to reduce glare. And it encouraged the use of 3000K (Kelvin scale) or lower LED lighting with proper shielding and consideration given to utilizing the ability for off-peak dimming.
The city is installing an LED streetlight that has a color temperature of 3000K to minimize blue light and glare as recommended by the AMA. The residential streetlight we selected is in the lowest tier for brightness available through the National Grid rate program.
It has a glare rating of 1 on a 0-5 scale when operated at its full brightness setting and the city is installing them at the lowest possible setting to achieve 43 percent less brightness. Our new LED streetlights will be configured to accept future dimming controls in line with the AMA’s recommendations.
A major concern in the guest column is that Northampton’s proposed LED streetlights lack proper shielding. The LED streetlight model we are installing, however, is fully shielded based on both the AMA’s community guidance and criteria set forth by the International Dark-Sky Association, a nonprofit founded by astronomers with a mission “to preserve and protect the night-time environment and our heritage of dark skies through quality outdoor lighting.”
The association goes one step further than the AMA in that it provides independent, third-party certification of LED streetlights based on a strict design criteria that includes requiring fixtures be fully shielded, minimize glare, reduce light trespass and not pollute the night sky. The LED streetlight the city is installing meets all of the criteria and earned the association’s “Fixture Seal of Approval.”
Additionally, both the AMA and the association recommend that even fully shielded lights have the option to be fitted with extra shielding to prevent light trespass into homes.
The city is following that recommendation, mapping out in advance over 150 locations where this may occur so that special house shields can be installed as part of the LED streetlight retrofit project. Going forward, the city will review on a case-by-case basis requests to add these house shields to a streetlight that is causing direct light trespass into a home.
Finally, Monday’s guest column implied that the Illuminating Engineering Society agrees with the AMA and cited them as one more expert the city was ignoring. If you read the IES statement cited and linked on Gazettenet.com, however, you will learn that IES did not endorse the AMA recommendations nor were they even consulted by the AMA, that IES believes the AMA report requires more scientific review, and most notably, that “of primary concern to the IES is the potential for this report and its ensuing press to misinform the public with incomplete or inaccurate claims and improper interpretations.”
Converting our 2,208 high-pressure sodium streetlights to LED will result in the city of Northampton using 75 percent less energy to light its streets, reducing our electric bill by about $180,000 annually. These reduced operating costs, together with over $210,000 in National Grid rebates, means this project pays for itself within five years. More importantly, reducing our municipal electric use by approximately 850,000 kilowatt hours a year – enough to power 120 homes – reduces our annual greenhouse gas emissions by approximately 300 metric tons of carbon dioxide.
Rest assured that Northampton’s LED streetlight program – developed after many months of design, professional consultation and a proactive field-test program initiated by the city to solicit public discussion and feedback – follows, not ignores, the advice of the American Medical Association and the International Dark-Sky Association with regard to mitigating the potential harmful effects of LEDs to humans, wildlife and the environment.
David J. Narkewicz is the mayor of Northampton.