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Solving climate change by abusing thermodynamic scaling laws

ckrapu.github.io

101–110 of 178 posts

Re: Solving climate change by abusing thermodynamic scaling laws

#101

Or. And I’m just spit balling here. Plant super long lived trees. Redwoods live for >200 years. Eucalyptus grow very quickly and might be a good option too.

I can do you one better. Plant those trees and when their growth (in terms of sequestered C02/year) start to plateau you cut them and either use them for construction or bury them in places where the conditions are right for coal formation. Since we understood the "coalification" process we can also manufacture such sites close to where said trees are planted.

In the latter case you bury the trees and forget them because accelerating coal synthesis is energy intensive, and so you can't really reuse that coal as it would be a net negative in our energy budget.

So you either are sequestering C02 and using it to create houses that will be around at least few decades (and in the process maybe also decrease the material cost of such constructions) or permanently sequester it in a way that only a few % of the sequestered C02 gets back into the atmosphere.

I can't find anymore the article that explains what I mentioned, but the issue is that is not economically profitable (is costs $$$ without generating a return with the current laws). However, I believe that if you account the damage climate change is doing around the world it is.

Re: Solving climate change by abusing thermodynamic scaling laws

#102

Earlier quoted context omitted.

The point is that you can have exponential growth in human energy consumption without exponentially heating the Earth by having the growth take place off-planet. Which is hardly irrelevant to the people still there, e.g. if you find your data centers are using too much power, put them in space. The computation may take a megawatt-hour but transmitting the result back to the surface is only a few watt-seconds for a ra…

> you can have exponential growth in human energy consumption without exponentially heating the Earth by having the growth take place off-planet No. It doesn't matter, unless you postulate that the people left behind have zero population growth and constant energy dissipation, which seems unrealistic? In any event exponential growth in human energy consumption is physically unrealizable. Eventually the whole solar sy…

> It doesn't matter, unless you postulate that the people left behind have zero population growth and constant energy dissipation, which seems unrealistic?

Why does it seem unrealistic? More than that, you only need one of those things. You could have population growth with declining energy consumption if energy use is moved off-planet (even if the population benefits from the off-planet use), or increasing local energy use per-capita if local population is declining, e.g. because the number of people leaving to explore other planets is higher than the population growth rate.

> Eventually the whole solar system resembles a red giant star, and sooner than you might think.

The universe is a lot bigger than the solar system.

> That's why you can't buy one even though there are videos on the YT showing how to make them.

Uh, nope. That's not why you can't buy one.

Re: Solving climate change by abusing thermodynamic scaling laws

#103
post #93

Oil formed over millions of years at a rate of about 80,000 barrels / year. We consume 36.4 billion barrels of oil per year. That means we consume oil about 455,000 times faster than it was originally produced. And this is just oil; I'm not counting coal and natural gas. Trying to reverse that process by taking a fraction of one year's plant growth and sequestering it is probably 5-6 orders of magnitude too little to…

especially since modern farming heavily uses oil based pesticides

I think it's more like 3-4 orders of magnitude (i.e. 1000 or 10000 of these sites), but yes, it would take quite a few to completely offset CO2 emissions.

Re: Solving climate change by abusing thermodynamic scaling laws

#104
post #82
post #37

Earlier quoted context omitted.

Sadly, I don't think so. Many of these carbon burial/sequestration proposals all advocate just taking all of the plant matter and tucking it away, including the N and P.

Eli Yablonovitch has been working on this for a while. I thought it was assumed that only the lignin would stay sequestered but I'm not finding those details. https://www.pnas.org/doi/10.1073/pnas.2217695120

I wasn't satisfied with his idea because it assumed that the biomass had to stay dry indefinitely, despite being locked behind an impermeable barrier. It's also not very convenient geographically, because raising crops (at least for low-value types like switchgrass) is not economically viable in the driest areas where they would be stored.

Re: Solving climate change by abusing thermodynamic scaling laws

#106

This year ie 2024 world will add more solar power than the total consumption growth. This is despite the tariffs and sanctions on Chinese panels and batteries. I think the world is at the cusp of dramatic change that would come faster if not for western countries trying to protect their industries. I think adding more renewables as fast as possible specially solar is the best option as this will make essentially ener…

So far we are still increasing the rate at which we extract fossil fuels, even with all the investment in renewables and alternate power sources in the last decades ( https://ourworldindata.org/fossil-fuels ). The Jevon paradox seem to still be valid in this, even with a few countries that managed to have most of their energy matrix on clean sources. And with all the time that CO2 remains in the atmosphere it is not…

The past decade does not matter as till this year consumption growth was more than renewables additions that has changed in 2023 and will accelerate from 2024. So the tipping point has just been reached add electrification of transport and heating and fossil fuel use will come down a lot faster than people owning fossil fuel reserves would like for the world to realize. In 2024 we will add almost more solar than all the solar installs in the world till 2020.

Re: Solving climate change by abusing thermodynamic scaling laws

#107
post #93

Oil formed over millions of years at a rate of about 80,000 barrels / year. We consume 36.4 billion barrels of oil per year. That means we consume oil about 455,000 times faster than it was originally produced. And this is just oil; I'm not counting coal and natural gas. Trying to reverse that process by taking a fraction of one year's plant growth and sequestering it is probably 5-6 orders of magnitude too little to…

But only a very miniscule fraction of carbon ends up as oil.

This paper made an attempt at a comparison of fossil fuel use versus agricultural biomass production: https://www.researchgate.net/figure/Global-annual-production...

I think plants convert 120 GtC from the atmosphere into biomass every year (ref https://www.worldbioenergy.org/uploads/Factsheet_Biomass%20p...) - obviously this is very roughly balanced by how much CO2 is naturally returned to the atmosphere. The additional anthropogenic CO2 emissions are 37 GtC.

So there is theoretically enough biomass for us to sequester - if we could do all that work without dramatically increasing our CO2 emissions...

Re: Solving climate change by abusing thermodynamic scaling laws

#108

Earlier quoted context omitted.

Sure, look at that chart. According to that chart, we'll burn coal forever. Now, consult reality for a moment, or take a look around. Coal is finite, a resources stored away over a tremendous period of time, much of it burned in about a century. So your "always" is at best temporarily true, and thus worthless, it can't actually have predictive power. Although you insist that new sources "always come on top" you're ei…

>Coal is finite, a resources stored away over a tremendous period of time, much of it burned in about a century Sure, it's finite, but we will run out of oil and natural gas much faster than of coal. There are centuries worth of known economically viable coal reserves. Even more, if we count low-quality lignite and peat reserves.

Do those 'centuries' include the large increases in power demands across the world, ( as the wider world develops ) and the requirement to replace the missing oil and gas when they run out?

Re: Solving climate change by abusing thermodynamic scaling laws

#109
post #11
post #2

What are you gonna do about all the nitrogen etc which the plants need? Are there good ways to reextract these nutrients from dead plant material without releasing loads of carbon at the same time?

I wonder the same. This proposal sounds like it is leeching nutrients from the ground and storing it for a long time (on a scale of centuries in the proposal). How do these nutrients cycle back for growing the food that we need? Or, for that matter, for the next round of biomass to freeze?

On a tiny scale I store them via humification in the top soil. In agriculture they manage the humus content of their soil anyway, for example in greenhouses they might have 20% instead of 2% in the surrounding fields.

Someone armed with enough VC money could possibly do that on a really large scale and even monetize it via carbon offset certs and then just throw the C rich output of their giant bioreactor into the bottomless pit.

Re: Solving climate change by abusing thermodynamic scaling laws

#110

Earlier quoted context omitted.

To put this statement into perspective, see this graph "Global primary energy consumption by source" https://ourworldindata.org/global-energy-200-years 1. Share of solar is negligible 2. New sources of energy have always come on top of existing sources, never replaced them

Sure, look at that chart. According to that chart, we'll burn coal forever. Now, consult reality for a moment, or take a look around. Coal is finite, a resources stored away over a tremendous period of time, much of it burned in about a century. So your "always" is at best temporarily true, and thus worthless, it can't actually have predictive power. Although you insist that new sources "always come on top" you're ei…

> Although you insist that new sources "always come on top" you're either just observing that the chart was designed this way (facile) or you didn't look at the actual data closely.

I mean that new energy sources came in addition to existing ones. We consume as much wood as we ever did. Coal didn't reduce wood usage. Oil didn't reduce coal and so on...

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