LED traffic lights don’t melt snow

Interesting story on MSNBC about how the newer energy-efficient LED traffic lights are causing accidents because, unlike conventional incandescent traffic lights, they do not generate enough heat to keep themselves clear of snow, and thus can easily become obscured by it. I don’t think anyone’s saying LED traffic lights are a bad idea in general, but it is an interesting parable about thinking all the way through a problem from a design perspective. [Thanks, Ron!]