Often overlooked energy consumption numbers.
LED traffic lights had a fatal flaw when first installed in cold weather states.
Traditional incandescent bulbs did not ice up in snow storms. LED lights run cooler and froze over with ice and snow. Thousands of accidents happened nation wide before the problem was identified.
LED traffic lights now have thermostat controlled heaters installed when used in cold weather climates. LED streetlights have the same problem with snow and ice buildup.
When people quote the power savings of LED lights for traffic and streetlights they neglect to include the power used by the heaters. Best case, the savings are minimal when the heaters are installed. In some cases the net power used is actually higher than an incandescent bulb.
The installation is also more complex and more prone to failure making the traffic lights less reliable.
