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Physics/Chemistry: Solid carbon (e.g coal) is more energy-dense than CO2 (per molecular weight unit). This is why you can gain energy from burning coal. To go t
by sonium 8y ago
Physics/Chemistry: Solid carbon (e.g coal) is more energy-dense than CO2 (per molecular weight unit). This is why you can gain energy from burning coal. To go the other way round you need to add this energy back in to break the very stable double-bonds in the CO2 molecule. This energy is what makes it expensive and there is no way around (except finding a really cheap energy source, but then you probably wouldn't burn coal in the first place)
- zaarn 8y agoI would, however, propose that once we have CO2-neutral energy production, we use some of it to recapture CO2 if the effect would be even minimal.
- majewsky 8y agoThe problem is that "once we have CO2-neutral energy production" is way too late. There are several tipping points where the rising temperature sets off other processes that speed up warming even further. For example, when the Russian permafrost melts, it will release gigantic amounts of methane, a very potent greenhouse gas, into the atmosphere. Once that happens, not only do you have to capture all the CO2 you emitted, you also have to capture all that methane. Also, you'll want to recreate the kilometers-thick ice sheets in the arctic. When those are gone, the earth's albedo will drop, which means that it heats up even more quickly since less sunlight is reflected.
- jamesblonde 8y agoYes, the clathrate gun hypothesis.
- zaarn 8y agoLet's also not forget the methan hydrate deposits on the coasts. Even minor temperature increase or pressure change at depth would cause them to explosively abandon their place. We have found 3km wide crates in the deep sea formed by such methane deposits going nuclear, I doubt such an event would be pleasant for nearby coastal regions.