According to an article by Kirsten Errick in Route Fifty, “Washington, D.C.’s decision to install new energy-efficient LED streetlights to reduce greenhouse gas emissions and costs is garnering attention from environmentalists who are concerned about the bright lights’ impact on people and wildlife.” As Errick points out, “The district is part of the 80% of North Americans that cannot see the Milky Way.”The D.C. case highlights the conflict between energy efficiency and the practical benefits of urban lighting and the negative impacts of light pollution. The project will save the District an estimated $2.5 million per year in energy costs, and LEDs can last five times as long as incandescent bulbs. But residents are already noticing the harsher lights, which can affect sleep and disturb human and animal circadian rhythms. “Even before the district’s LED project, the city was already excessively lighting its streets, s. It is unclear why the district overlights, but the city is currently not considering making changes to this practice, according to city officials.” Errick notes that “Current non-LED lights in the district are approximately seven times the national lighting standard, recommended by the American Association of State Highway and Transportation Officials, while the new LED lights will only be two to three times as bright as the standard.”Dark sky experts like Jim Dougherty of the International Dark Sky Association say cities can accomplish safe street lighting without overlighting, comparing lighting to music: “Music is supposed to be kind of loud, but then cranking up the volume by three more notches doesn’t help you, so you should put it on spec,” Dougherty said.

Source: Forbes May 30, 2023 17:24 UTC