Do burnt-out fluorescent light bulbs still consume electricity when the light switch is on?
There are several things that can cause a fluorescent light to stop working. If the filament breaks, then there is no circuit, and it won’t draw any power. However, lights that have lasted a long time will eventually stop working due to lack of “emission mix”, phosphor, or mercury. In this scenario the light will still draw power, but won’t light up. Fortunately, loss of these materials will also cause the tube to overheat, which will cause the filament to burn out, and the circuit will be broken. This will happen fairly quickly, so it won’t be drawing power for very long after it goes out. Wikipedia has a longer, more technical explanation, which can be found at the provided link. Hope that helps! Sources: http://en.wikipedia.
Flourescent tube lights work by agitating a gas inside the tube, which causes the coating on the inside of the tube to glow. If the light is blown, then it’s usually because there is a leak, and the gas has escaped. Since normal air replaces the gas, it doesn’t get excited, and so does not cause the coating to flouresce. Since air is an isulator (generally) then there can be no current passing through, and no power usage. However, I believe that electricity CAN seep from sockets, power cables, exposed contacts, etc, but at a rate too small to measure. There you go…
