Lightbulbs and CO2

[takyi]

I had an arguement about this topic and I'm not sure if I was right or not. Do lightbulbs produce carbon dioxide? I am not talking about the power plants that burn fossil fuels to produce CO2 but the light bulb itself. I am not sure if it does or doesn't create CO2. If it does please specify how much CO2 an average light bulb would produce if you know.

[greenrealist]

Incandescent bulbs don't give off carbon dioxide themselves. The light is created by passing an electric current through a thin filament (usually tungsten). As the filament is within a sealed glass environment there is no access to oxygen and so a combustion process does not take place.

Only about 10% of the resulting light is withinin the visible spectrum which makes incandescent bulbs a pretty inefficient way to obtain light. LEDs and flourescent lights produce a greater percentage of visible light using far less energy.

The main carbon impact of incandescent bulbs is, as you have already noted, the additional electricity that they require. As a substantial proportion of Grid electricity comes from fossil fuel generation this inefficient form of light is more carbon intensive than energy saving bulbs. However, the carbon impact of bulbs does not end there. There is also the carbon dioxide produced in the manufacture of the bulb itself. The glass and metal sectors are both carbon intensive. This makes the considerably longer product life of an energy saving bulb yet another significant environmental benefit (less glass, metal and process emissions).

Hope this helps.

Greenrealist.