Targeting the preindustrial level of atmospheric CO2 is such an ambitious target, trying to undo 300 years of emissions. Then again, it’s not like we’ve stopped emitting.
If we instead try to calculate the energy requirements to simply offset the average emissions of that particular year, using this formula of 652 kJ/kg CO2, and average annual CO2 emissions, against the current numbers of about 37 billion tonnes, or 37,000,000,000,000 kg, we have 2.4 x 10^16 kJ, or 2.4 x 10^19 joules. Which converts to 6.7 x 10^12 kWh, or 6,700 TWh.
Total annual US electricity generation is about 4700 TWh per year.
Global electricity generation is about 25000 TWh per year, about 40% of which is from low or zero carbon sources.
So basically if we’ve got 6700 TWh of clean energy to spare, it would be more effective to steer that into replacing fossil fuels first, and then once we hit a point of diminishing returns there, explore the much less efficient options of direct capture for excess energy we can’t store or transport. Maybe we’ll get there in a decade or two, but for now it doesn’t make any sense.
If we wanted to remove enough CO2 to get back to the preindustrial level of 280 ppm, it would take 2.39 x 10^20 joules of energy. For a reality check, that’s almost as much as the world’s total annual energy consumption (5.8 x 10^21 joules every year).
Isn’t that over an order of magnitude difference? What am I missing? How is that “almost as much”?
I didn’t read the article but it seems off. With only 1/20 of energy used by the world in a single year we could undo the damage of 300 years?
Seems too low. If that’s true we could shut down completely for just two weeks to undo
Can’t imagine “shutting down completely for just two weeks” would exactly be reasonable, but yeah I wonder if the article had a typo in it. I’m not sure. As of right now, the numbers are still the same in the article.
If the numbers are correct, expending like 5-10% of our energy expenditure for a single year on carbon capture sounds a lot more reasonable than the article suggests. Even if it were half of our yearly energy usage, that sounds pretty reasonable if you draw that out over a few decades.
This is why STEM education is important. You clearly learned from yours and that’s awesome!
I’m guessing they don’t understand scientific notation, and “numbers are close” without understanding the numbers are much more significant
Yep, it’s close to 4% of the total. Not really “almost as much”.
That’s honestly pretty good, I can see world leaders coming together and just doing that. There must be other technical challenges to this other than raw power usage
I don’t know much about the technology, so I can’t comment on that. But I don’t really see politicians pushing for this, at least not succesfully. There are too many rightwing obstructionists in most Western governments right now…
Other than the currently dying Tory party (and even sort of them), every single major UK political party is for green energy and against climate change to varying degrees. And I mean on a policy level, not just words.
I’m not too familiar with other governments, but Europe seems to be going well on that front too. And as much as China bad, they seem open to green policies, and the US democrats seem pretty okay on climate, especially as carbon capture helps out fossil fuel companies.
I know that’s not a massive ringing endorsement, but considering the cost of 4% energy expenditure for a single year, it seems like a no brainer. If you spread it over 20 years that’s 0.2% of energy, less than AI or crypto uses by far
It depends on the method. IIRC, the most cost effective methods cost more than leaving it there. The real problem really is figuring out how to make a profit off it. Without the government forcing it subsidizing it, nobody will do it, even sustainably, in volume enough to matter.
Algae does it for free all the time. Physically trying to capture carbon dioxide is dumbassery. We need more investment in algae production.
Algae doesn’t capture it for long. Trees do it for longer but not long enough to be more then a speed bump. Unless we start dumping algae and trees into giant pits and sealing them up three is no long term carbon capture.
Algae doesn’t capture it for long.
Not true, it depends on how it’s contained. Drying algae and removing the water will stop it from decomposing. Think of seaweed used for sushi except ground up into a very dense powder. Algae will decompose if left hydrated in the sun though.
It could be beneficial for densely populated areas, though. Because you have predictable airflow and low-hanging regions to implement physical capture and sequestering. We can do more than one thing at a time and targeted approaches combined with generalized approaches will yield faster results.
In order for that we need more renewable energy, otherwise we’re just burning fossil fuel, producing carbon dioxide, and then capturing it. Solar, wind, algae biofuel, renewable diesel, green hydrogen, etc. We have to be careful how we use energy otherwise we’re just producing carbon dioxide to capture carbon dioxide.
TL;DR: the total energy produced by humanity in a year.
Or if you want to do it in let’s say 20 years, 5% of the total power output.
It’s way less than that. 2.39x10^20 is around 4% of 5.8x10^21. Not even close to “almost as much”. Looks like the authors don’t know their powers of 10. So if we dedicate 5% of the total energy for one year it could theoretically be done.
None. They are called trees. We should stop wrecking things.
To be fair trees still use energy for doing this, but that energy is conveniently provided by the sun.
If humans could make a profit off of killing the sun, they would.
We should try with solar farms
How does that destroy the sun? Unless I have the wrong idea of what a solar farm is. I’m imagining a big ol’ flat farmland in the middle of kansas with thousands of solar panels.
By stealing its photons!
(it’s a joke)
“Since the beginning of time, man has yearned to destroy the sun.” - Mr. Burns
Carbon capture makes much more sense directly on smokestacks and other industry waste outputs, but then how do businesses make taxpayers fund it?
Idk, I just feel like it’s 1. A cop out. We need to reduce emissions and not put our eggs in one basket. And 2. In its infancy. The tech isn’t efficient enough yet to be rolled out imo
I think we should pursue it for the future, but it shouldn’t be taking funding that could be used for more immediate solutions or used as a distraction / delay tactic (although of course it will).
Preventing additional carbon emissions doesn’t decrease what’s already in the atmosphere. We would need some form of carbon capture even if we stopped all emissions today.
Actually a thorough article from Wired. Oh…written by an Associate Professor, that’s why.
Basically… A lot! Just to have what effectively amounts to a painkiller. Now don’t get me wrong, those are great but you know what’s better? Solving the issue that causes you pain to begin with.
Hmm …what about continuing to go on benders every night and not addressing the problem at all? Would that be bad?
Sounds like a great use for nuclear and then if there’s a drop in renewable energy it can pick up the slack
At this point, we need to do both
Casey Handmer seems to think there’s still an opportunity here. There are updated versions of that post, but I think this was his first on the topic.