I’m listening to a podcast and the lady says we eventually will need to become a net 0 society and then go negative to reverse the effects of climate change.
This entails sucking carbon from the atmosphere. Why can’t we just invest in this now and keep our oil and coal energy? What can this carbon be used for once we have taken it from the atmosphere? She says we just pump it into the ground?
In: Engineering
Because it requires a lot of energy to do, and it doesn’t make enough money. Money is more important than the future most of the investors won’t be a part of. On that note, convenience is more important than the future, as well.
Net 0 is ages away from today.
There are natural processes that will pull CO2 out of the air, but they don’t work fast enough to keep pace with human production.
CO2 is a gas, so storing it underground is a possibility, provided you prevent leaks. What we don’t have the energy to do is turn it into C and O2. If we could do that, the C would be super-pure coal, and we could burn it. However, even if we used 100% of the energy from burning this coal to separate C from O2, we’d still have to add more energy to break even.
Renewable energy is great, in the amounts we have. However, that’s only a tiny fraction of human energy use.
This process is called carbon sequestration. It’s not *exactly* just dumping solid carbon into the ground, but rather using carbon-based compounds in ways that nature can naturally absorb it.
There is a finite amount of carbon (and every other element) on the earth. The problem now is that the balance of it has shifted, where more of the earth’s carbon used to be underground in hydrocarbon chains forming petroleum, coal, and natural gas, a lot of it has been released into atmosphere as carbon dioxide gas. The simplest form of carbon sequestration is tree planting, as they absorb CO2 from the air and use it to form lignin and cellulose, more commonly known as wood. Dead trees’ carbon is either consumed by decomposers, which eventually die and become part of the soil, or is harvested for construction, where it can stay lit for a very long time. Some of it is burned, re-releasing the carbon.
Industrial-scale carbon sequestration is also possible, but very difficult as CO2 is a very stable compound; it’s hard to separate into elemental oxygen and carbon.
Well, when we burn a kilo of coal, we produce something like 3.6 kilos of co2. By volume, that’s a huge amount of gas. Far more than we can store anywhere.
To absorb this gas and convert it to something else, we need a shitload of energy. More than we get from producing it. So, we have this circular issue that requires non-carbon energy sources.
In the past, this non-carbon source has been the sun, which powers trees/other plants to break down and store carbon.
Energy produced from oil and coal creates carbondioxide aka CO2 as an undesirable byproduct. Whenever these materials are burned (in power plants, in cars, etc), CO2 is released into the atmosphere.
The point of using renewable energy is so that no CO2 is emitted. So you can see that to continue using coal and oil as energy sources defeats the purpose of using renewable sources instead. There’s no way around doing so during a transition period, but the goal should be to stop using coal and oil altogether.
CO2 captured from the atmosphere is useless to us. We want to keep it somewhere it can’t escape back into the atmosphere so pumping it into the ground (then sealing it) is an option.
The scientific community is putting resources towards more sustainable power generation such as gen 4 nuclear reactors and wavelength converters for solar cell. However in many of these areas the material science isn’t where it needs to be yet to completely replace existing power implementations. As far as pulling carbon from the atmosphere, it can be very costly to do this and doesn’t seem to be worth the energy expenditure. There are other alternatives like certain electrochemisty related effects that can create things like methanol and ethanol but they are very difficult to scale production.
Capturing carbon with currently known technologies is inefficient and expensive to do compared to simply changing the way we make energy.
Imagine making electricity by burning coal. The carbon dioxide and other pollutants are a glass of cool aid and it gets dumped into a swimming pool, representing our atmosphere.
It’s a lot easier to simply find a way to make electricity that doesn’t result in dumping cool aid into the pool than to try to suck out the *very diffuse* cool aid from the pool.
Wind and solar are better ways to do that.
The power cost for extracting carbon from the atmosphere would exceed the benefit.
Long-term, it’s almost certain to be the wrong approach as well. Instead of worrying about the consumption end, focusing on the production end solves not just the emission problem but the resource availability problem. That is, manufacturing petroleum instead of pumping it from the ground.
Important to note that laws of physics tell you that, simplified, if you earn $1,000 for burning coal and releasing coal into atmosphere, it costs you at least $2,000 to catch it, probably way more.
So if you are going to take climate action, burning coal is at best a huge waste of money as you then need to expend way more into recapturing equivalent amount of coal that you released, giving you a totally pointless net loss.
But in less simplistic terms, you can think of that as taking a loan from the bank, and extra cost as interest laws of physics demand from you. In this view, humanity is currently taking a huuuuuge loan with absolutely no plans in place about paying it back. But still, you can have reasonable loans.
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