Taxing the point at which the CO2 is created makes the most sense, then you don't have to try back or forward tracking penalties or incentives through the chain to incentivize carbon efficiency.
What makes you think polluting power plants would not pass on costs to consumers?
I'd propose instead a tax at the point of extraction. Our issue lies In the fact that we are adding to the carbon cycle faster than geologic processes can sequester it back into the Earth. Disincentivizing mining and drilling operations, and creating incentives for sequestration, are the only solutions that stick on the scale of a lifetime.
It isn't easy.
> I'd propose instead a tax at the point of extraction.
Is this based on anything serious? The problem is greenhouse gas emission into the atmosphere, not extraction of chemicals containing carbon from the ground.
Where does biological methane emission from farming or GHG release from clearing forests figure in the "extraction"? Why should natural gas that's used to manufacture "blue hydrogen" incur as much tax as that which is burnt directly?
> Our issue lies In the fact that we are adding to the carbon cycle faster than geologic processes can sequester it back into the Earth. Disincentivizing mining and drilling operations, and creating incentives for sequestration, are the only solutions that stick on the scale of a lifetime.
The issue is entirely atmospheric GHG, so taxing at the point of emission is the most efficient way to reduce that, all else being equal. If there are specific cases that are much easier to account at downstream consumption or upstream production then at some point it would be more efficient to account those and pass costs along, but you wouldn't go all the way back to extraction if you could avoid it (e.g., gasoline or domestic natural gas producers or distributors may incur the tax rather than individual people burning it, but probably not the wells).
If a large portion of carbon greenhouse gas emission is from burning of extracted chemicals, and a large portion of extracted chemicals are burned it seems to me simply taxing the chemical extraction itself is a good start, as it is simple to implement. I agree that taxing exactly at the point where emission occurs is ideal, but if that's too complicated to do right away starting with something simpler with a similar result is a good idea.