Unintended consequences of environmentalism: LED traffic light edition

Steven Horwitz at the Austrian Economists blog explains that

Apparently a number of communities in the Green Bay, WI area recently installed some energy-conserving LED traffic lights as an environmentalist gesture. The unintended consequence? The lights don't give off enough heat to melt ice and snow, which means during snowstorms the lights are obscured by the snow, which has led to a number of automobile accidents. The further result is that city crews have had to manually scrape the lights.

Horwitz goes on to note

So in attempting to save a fractional amount of energy, we have not only risked human life and limb (and perhaps damaged some), we have caused a number of unnecessary accidents, each of which will require various forms of energy-usage to fix (everything from tow-trucks to body shops use energy you know), and we have diverted human labor from more highly valued uses (such as clearing other roads to prevent further accidents) to scraping traffic lights that should not have needed scraping in the first place.