The city of Lawrence is right to proceed with new LED lighting despite an American Medical Association recommendation to use lower intensity lights.
Last year, the AMA issued guidelines warning against using high-intensity LED lights for streetlights. The AMA said such lighting emits a large amount of blue light that can create worse nighttime glares, affect sleep patterns and disorient some animal species. The AMA recommends that LED lights be no brighter than 3,000 kelvins.
The city has allocated $4.4 million for new LED lighting in facilities, along some roadways and for some public outdoor spaces. The LED lights are more energy efficient and last longer. Transitioning to LED lights is expected to save the city about $225,000 annually. All the LED lighting the city is installing, including the outdoor lighting, ranges between 3,500 kelvins and 4,500 kelvins.
Adrian L. Melott, a professor in the department of physics and astronomy at the University of Kansas, urged the city to reconsider its plans. “There are towns in America where they are tearing out the LED lights they put in to put in lower-color temperature ones,” Melott said. “We don’t want to get ourselves into that fix. It’s easier to switch now than to have to tear them out later.”
But there are varying opinions on the AMA recommendation. The lighting industry has vigorously challenged the accuracy of the AMA’s advisory. And the Department of Energy issued a response that said the effects of exposure to blue light at night also apply to light from television, phone and computer screens and depend on the amount of light and duration of exposure.
Lawrence-Douglas County Sustainability Director Eileen Horn said the AMA recommendation wasn’t issued until the city was well into its project. Ultimately, the city followed the recommendation of the Lawrence-based general contractors for the project, 360 Energy Engineers, to continue with its original lighting plans.
Changing course on lighting now would be cost prohibitive.
It’s noteworthy that the AMA advisory is specific to streetlights and does not specify how much exposure to high intensity lighting is harmful. The city owns about 20 percent of the outdoor lighting in Lawrence, with the rest owned and operated by Westar. Including traffic lights, Westar owns 3,500 lights while the city owns about 800 street, pedestrian or parking lot lights. Westar is also converting to LED lights and is using 4,000-kelvin lights.
The purpose of the switch to LED lighting is to achieve efficiency that leads to reduced costs. Switching LED lighting intensity at this point would undercut those efforts. More research on high-intensity lighting is expected, and if that research leads to more specific recommendations from the AMA, the city can take steps to address the lighting issue at that time.