Green Goes Bad: LED Traffic Lights Can't Melt Snow, Cause Accidents - Traffic Signals - JalopnikJalopnik said:New-fangled LED traffic lights last longer, pierce the darkness more effectively and consume 90% less energy than incandescent bulbs. That's also their drawback. They're not hot enough to melt snow that sticks to their lenses, causing dozens of accidents.
LED's are, by design, more thermally efficient than incandescent bulbs, meaning more of the electricity is turned into light and less into heat. Incandescent bulbs are generally considered to "waste" electricity as a result of this thermal inefficiency, but in the case of traffic lights in northern climes there's a happy benefit, the "waste" heat melts snow so, you know, people can see the lights.
Police departments across the northern United States are noticing an uptick in accidents related to snow-packed LED traffic signals. Whereas incandescent bulbs melt the snow, the LED units cannot and the snow blocks all the light. The problem happens during heavy, wet snows with high cross winds, and can persist as long as the temperature hasn't raised to naturally melt the snow (or road crews clean the lights by hand).
Why motorists are dumb enough to take this as an indication to just barrel through an intersection into an accident is beyond us. We'd think they'd be smart enough to simply treat the situation the same as a power outage, approaching the intersection as a four-way stop. Although there's no solution to the problem, although it seems a gentle heating element attached to a nifty sensor would do the job — but such a device would certainly cut into the energy savings benefit from LED signals (sorry Greenies, better luck next time!). Another option? Motorists practicing defensive driving. Yeah, like that'll happen.