What are the effects/outcomes of sending emissions deep into the ground, instead of into the atmosphere?


Hi guys! I was in the shower this morning and I had one of those thoughts, so now I’m here.

So, I want to start at the beginning of my thought process.

When plants and animals die, they are decomposed by microbes into chemicals, including carbon dioxide.

To make a long process short, I’ll just say that oil humanity currently consumes was originally from the death of plants and animals hundreds of millions of years ago.

Now, I don’t know the exact process for how CO2 becomes petroleum (CnH2n+2), but I do know that energy cannot be created or destroyed, so the Carbon in our emissions is the same Carbon molecule that was stored underground in the liquid form petroleum, and ultimately are the same carbon molecules that made up plants and animals millions of years ago. So if we funneled the Carbon Dioxide that we currently emit into the atmosphere (from something like power plants, cars probably wouldn’t work) back into the ground, would nature/geology not continue it’s regular process of turning the gas CO2 back into crude oil over hundreds of millions of years?

I understand there may be more to this process. For example, the fact that crude oil contains Hydrogen tells me there is likely water involved in the process, but I don’t understand why something like that would be a factor. The only potential issues I could see are the possibilities that injecting gases deep into the ground could make the ground unstable, or the gases may slowly leak out through the Earth (in which case, at least SOME of the Carbon Dioxide would still be absorbed into the ground).

Please help me understand! And thank you ahead of time.

TLDR; What would be the effects of returning emissions to where the fuel came from?

In: Other

Carbon capture and storage is a thing. However, it is both expensive and unreliable. There are a lot of concerns about the ability to avoid leakage in the process.

It is, generally speaking, way less expensive to get energy in a way that emits less carbon than to try to capture and store the carbon that comes from a dirtier energy source.

As for the long term impacts on the CO2 of storing CO2 underground I’m not sure. Generally, the main way CO2 leaves the atmosphere is when it is fixed through photosynthesis. The fossil fuels we use weren’t created from CO2 trapped underground, but other hydrocarbons (i.e. the material from ancient plants).

First things first, get rid of this notion that matter and energy can’t be created or destroyed. Its true, but doesn’t really have anything to do with this problem, and is generally misunderstood in the process. For example, stars like the sun routinely convert hydrogen (an element) into helium (a different element) and energy, while processes here on earth can combines elements like oxygen and carbon into CO2 while producing energy, or can break apart CO2 into carbon and oxygen by using up energy.

So, all that out of the way, lets tackle your question. Plants and animals are comprised largely of carbon. This has always been true on earth. We’re carbon based life forms after all. Millions of years ago, plants and animals wound up buried under the ground, trapping all that carbon under the ground. Over time, and using energy from the earth, that carbon was converted into/incorporated into various fossil fuels like coal, oil, or natural gas.

Today, we dig up those fuels and burn them. This combines the trapped carbon with atmospheric oxygen, creating CO2 and heat energy, which we use to power things. So we don’t necessarily need to trap that CO2 back underground, though that is a strategy that some people are working on.

Instead, if a cheap/low power method could be discovered to break apart the CO2, the oxygen could be released, and the carbon trapped back underground. The issue really is that if combining two elements resulted in/from energy creation, breaking them apart will also require more energy from somewhere.

It’ll likely be more efficient to just get power from non carbon based processes, and cut out the effort to recapture and break apart that CO2.