I would like to know how much energy it takes, in the modern world, to construct an ordinary, ready-to-buy light bulb, from the raw materials in the ground.
In the end, I would like to know it for the following types of bulbs:
- Fluorescent tube
For example, to create a tungsten-filament light bulb, you would need
- a few types of metal
- a few types of plastic
- a mixture of gases inside the bulb
- cardboard and plastics for the packaging
These raw materials all require energy input:
- extracting tungsten from the ores, ..., creating filaments, ...
- creating the right kind of glasses, ..., creating bulb housing, ...
- of all the materials to their respective factories
- of all the (half-)products to the bulb factory
- of the bulb to the distribution centers/shop
- a small percentage of the raw materials will be rejected
- a small percentage of the finished light bulbs will not work, and get rejected
- energy expenditure of the robotic components and other tools in the involved factories
I realize this is virtually impossible to answer accurately for even a specific light bulb from a specific store, let alone make general statements -- there are simply too many steps in between to be able to trace everything "back to the ground".
What I'm looking for, is authorative sources on this subject. Studies done on the energy demands of modern production lines, hopefully, with this type of product in particular. I'd like to come to a more complete list than the one above, and some reasonable estimates on the energy expenditure in each step, ideally for each type of lightbulb.