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FX2032-2 t1_j83ox3k wrote

This sort of "Carbon capture" is really ridiculous. We burn carbon for a very good reason - it releases lots of energy, producing CO2. If we want to reverse the process we have to put even more energy in.
SO if you have free energy about to do carbon capture you are MUCH better off just using that energy to do what ever you were burning the carbon for in the first place!

As to converting the plastic, you can do that without any additional energy input (it is after all basically oil!) Cf. "Quantafuel".

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howard416 t1_j83rony wrote

Yeah but we might not have a choice about using direct air capture in the future

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abeorch t1_j83vmva wrote

Your argument has a point but we are not talking about just fuels. You are right in that the energy would be most efficiently used to avoid extraction of more fossil fuel but..

In this case we are reusing plastic produced from Oil rather than discarding it. We have a large stock of plastic that we have no use for. Do we bury it, burn it (releasing CO2) or can we reuse it?

Re using this as a substitute for fuels or plastic feedstocks that have no ready sustainable replacement reduces the net amount of carbon emitted. Ideally we would have substitutes for every application but we dont yet (Jet fuel being a good example but we also dont have good substitutes for many plastics either) so these provide more pathways for non-polluting energy to be added to the mix.

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herscher12 t1_j83zlx4 wrote

"Trees are to inefficient, lets replace them with solarpanels and make our own air"

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Codydw12 t1_j843pc4 wrote

In some cases, yeah. Can't plant a tree on a space station.

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MEMENARDO_DANK_VINCI t1_j8519vr wrote

I’m gonna tell you, we’re absolutely going to plant a tree on a space station, just not yet

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Codydw12 t1_j854n8u wrote

In a couple decades probably. If we can get space farming going then space forests would act as massive nature preserves. Just near term I think artifical scrubers would do better.

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taedrin t1_j84igqs wrote

>SO if you have free energy about to do carbon capture you are MUCH better off just using that energy to do what ever you were burning the carbon for in the first place!

There are a variety of applications where being tethered to a grid or using a battery are not practical. Fuel is convenient because it has insane energy density and certain kinds of fuel can be kept for years without degrading. The amount of raw energy contained in a sizeable gas can would be too heavy for a human to carry if it were a battery. A $20 gas can with $4 of gas contains more energy than my $25,000 battery backup system, for example. And while extracting useful work from fuel is often inefficient, using the fuel for something like heating is practically 100% efficient.

Long story short, we will always have a use for fuel, so being able to sustainably produce it is useful.

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Initialised t1_j869t4g wrote

But if the fuel is electricity + plastic + CO2 then it’s not sustainable because the plastic component is fossil fuel.

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PatternParticular963 t1_j83qfdw wrote

But it is a way to store engery that we already understand very well. And one we already have the necessary infrastucture for. It could for instance be used to Transport solar energy lossless from say the Sahara to Europa. Will it yield in the end? Who can say? I'm not saying it is the way forward but it could well be one pillar among many, possibly giving us oportunities we didn't have before

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could_use_a_snack t1_j84ub2k wrote

As others have pointed out this idea isn't to create new energy, it's to get rid of garbage in a way that produces energy as a by product instead of producing different waste as a by product. At least that's how I'm reading it.

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Surur t1_j85h14i wrote

When talking about plastic, are they not the perfect carbon capture vehicle, since they don't decompose?

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