Are Energy-Saving LED Lights Also Creating Glaring Problems?

LED streetlights "shine brightly while using less energy than traditional bulbs," reports the Washington Post. After switching to LED streetlights one county in Washington state conserved 2,612,491 kilowatt-hours. But they also discovered a downside. "One year after the change began, the additional glare masked about half of the previously visible stars."Over the past decade, scientists found, the night sky has become nearly 10% brighter each year because of artificial lights, mainly LEDs emitting too much glare. Streetlights are part of the problem, as are sources such as illuminated billboards and stadium lights. Those same outdoor lights are also affecting our health. Common types of LED lights contain higher proportions of bluer wavelengths, which can affect people's nighttime patterns... Without melatonin to trigger sleepiness, people are more likely to stay awake longer. Disruptions in our circadian rhythm have been linked to cancer cases, such as breast cancer, and labeled probably carcinogenic by the World Health Organization. Other research has shown interruptions to our circadian rhythm are linked to some heart problems. The article has suggestions for your home - everything from blackout curtains to equipping lights with motion detectors or timers and dimmers. And when shopping for new bulbs, "Because our eyes are sensitive to blue light at night, doctors recommend buying LED lights with warmer-color hues, such as yellow or amber. That means using LED lights below 4,000 Kelvin." City governments are already taking this seriously, according to the article. ("Some cities, such as the District of Columbia, paused a transition to LEDs after residents complained about the bright lights disrupting their sleep.") The article even includes a photo from the International Space Station showing how two cities appear differently from space because they used a different shade of LED light for their street lights. One thing's certain: the popularity of LED lights is expected to continue:They consume up to 90% less energy and can last up to 25 times longer than traditional incandescent lights. As the most energy-efficient bulb on the market, it's no surprise that so many people are adopting the technology. The Energy Department estimated LEDs made up about 19 percent of all lighting installations in 2017, saving about 1 percent of total energy consumed in the United States. By 2035, the lights are expected to comprise 84 percent of lighting installations. Roadways, parking, building exteriors and area lights - which are applications typically high in lumens, a measure of brightness - are expected to see nearly full conversion to LED lights by 2035.

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