As the LED gives off very little heat it is now insufficient to melt away the built up snow and frost and has been cited as contributing towards at least one fatal road accident.
I suppose the big question is how did this ‘natural’ glass cleaning action get overlooked?. Was it that the engineer/inventor did not take into account the entire ‘system’ and thereby was so keen to save energy that other aspects of the system were ignored? I guess the old warm glass of the old lights was by accident rather than by design.
In TRIZ terms the heat of the old incandescent light bulbs would have been identified as a ‘harm’ to the system (thereby wasting energy) but perhaps inadvertently this would be converted to a ‘benefit’ during the winter when it would melt frost, snow and ice to maintain visibility.
This is also another of those ‘hindsight’ situations of ‘well it should have been obvious to the engineer/inventor, shouldn’t it!’. No doubt Obama will be ordering an immediate return to the old bulbs or adding expensive winter heating elements to every traffic light across the U.S.
I quite like the ‘simple’ feedback-based solution quoted on the ABC news site:
In the meantime, the Department of Transportation uses big sticks to clean off the lights when it gets calls from drivers who complain.
I just wonder whether this is now a problem with car lights which are increasingly using banks of LEDs and may well have a reduced ice melting capability.
Perhaps just as worrying the picture above looks like it has been set up by journalists pelting the traffic lights with snowballs which would obscure any warning lights whatever the bulb type.