I empathize with people who are trying to help by reducing their footprint. Though I fear it'll all be in vain when a machine is invented that can suck a lifetime's worth of frugality out of the air in a fraction of a second.
Regrettably, the numbers involved make me pessimistic. I think your idea of some deus ex machina technology is ungrounded optimism, wishful thinking, or denial. Nothing in the linked article gives any cause for such optimism.
Climate change math is like the ballistics equation. It is just a cold hard reality check. There is no free lunch in terms of the energy of a chemical reaction.
We are all getting really, really close to failing here. I think it's imperative not to be hopeless about it, but we should be honest with ourselves that we may not have modern human civilization as we understand it within a generation or two [edit: unless we act immediately, not soon]
I expect that we will eventually develop technology for CO2 extraction, but it's not going to be easy or convenient. 500 joules per kilogram is a lot and I doubt chemical methods will beat it. Currently there are about 3.5 trillion tonnes of CO2 in the atmosphere, or about 3.5 * 10^15 kg. To decrease the concentration by 1/3, returning us to preindustrial CO2 levels, you'd need about 600 petajoules or 170 terawatt-hours of input energy assuming thermodynamically perfect isothermal compression (which is impossible to actually achieve). Global world electricity consumption per year is about 21000 TWh.
No current method of CO2 extraction comes close to this limit and it's very unlikely that any ever will. Nonetheless, we have several orders of magnitude of wiggle room to let real-life methods work out okay. But the energy cost is not small and the negative effects of present-day CO2 emissions should not be considered easily curable.
And just for the fun of it, a human being releases about 4 * 10^5 kg of CO2 during their lifetime, requiring about 2 * 10^8 J. So the most efficient CO2 pump possible would require at least 200 million watts of power (about a thousand Tesla Roadsters at maximum output) to confine this CO2 within a second.
Also, you can't restore the initial pressure because at the initial pressure the CO2 takes up a whole atmosphere of space!
I didn't get your last line though. I assume you compress "dirty" air.
To be clear: all real processes probably require many times more energy than this. There is no way I know of to selectively compress one component of a gas mixture. But if you did, this would be the energy cost.
I'm afraid it will be more than that - but how much more exactly?
The reason for calculating the bare minimum "magic compressor" cost is because it also applies to techniques like pressure-swing adsorption:
https://en.wikipedia.org/wiki/Pressure_swing_adsorption
Using PSA can reduce the energy cost of CO2 extraction significantly relative to direct compression technology. But because we know that the adsorbent is used in a cyclic process, we have dW[compression] = p dV + dE[adsorbent] and the long-time integral of dE[adsorbent] is effectively zero because the adsorbent cannot absorb or release energy forever, so ΔW[compression] = int[p dV] and thus any technology, compression-based or not, incorporating some finite amount of external components, is subject to the work limit.
This is also why, for example, thermodynamic analyses of engine types are always concerned about the possible compression ratio. You could consider the partial pressure of atmospheric and stored CO2 as the compression ratio of a hypothetical compressed-air motor, which can then be run to extract thermal energy (i.e. violate the second law of thermodynamics) from any process more efficient than 500 J/kg CO2, since again W[motor] = int[p dV]. You can improve the compression ratio by taking advantage of the P-T curve and performing the whole compression at the South Pole, which saves you about 100 J/kg.
Also, I was off by a factor of ten when I plugged in the vapor pressure of CO2. Correcting this is left as an exercise to the reader.
Technologies not subject to the work limit include e.g. olivine crushing, somehow inhibiting volcanic activity (???), planting trees, etc. Another technology I just thought of would be to to form CO2@H2O clathrates in seawater starting with air, which would also lower the compression ratio, and extracting the (solid) clathrates to recover CO2 and desalinated water. Here the pressure required is much lower and additionally desalinated water is produced; this only works if we form the clathrates in a cold environment and decompose them in a warm one, which is kind of inconvenient. Then again, shipping gigatons of fresh water to LA might become necessary anyway!
In the same way that a year's worth of health insurance is wasted if you don't get sick. So, not wasted.
Considering how much excise taxes Europeans pay on their gasoline, you would think that climate change would already be a solved issue. Taxes are a larger part of the cost of gasoline than the gasoline itself. Yet somehow there isn't enough money to fight climate change?! The Netherlands pays $3.53 per gallon purely in excise taxes.[0] Bulgaria, a country with an average income of $9000 a year[1], pays $1.61 a gallon in excise taxes.
They do not address the fundamental causes of emissions which are steadily growing.
They have some merits for mitigation of the problem but not as a long-term solution
We cut forests, and burned oil. Offsets help revert one of these things. But, we’d need to do more than that to reverse the change.
So the offsets you can buy now are low hanging fruit. Actual carbon sucking costs vastly more than wren’s offsets.
Though still achiveble? Would be about $10,000 usd per person at average european emissions. About $20,000 usd per person at average american emisisons. Includes children.
https://climeworks.shop/?utm_source=CW-Website&utm_medium=ba...
If those costs go down, the costs become realistic. I don’t mean politically realistic, just possible to do.
Fwiw I use both wren and climeworks. And maybe if enough people used wren they might find non-forest offsets that are achievable at low cost. But right now it wouldn’t obviously scale if all did it.
So... you're saying that there's not an accumulation of plastic waste / microplastics in the environment, or that we know any impacts or benign or negligible?
Good news if true, would like to know what position there's the most credible evidence for.
> and "landfills = bad".
I'm a fan of consumer goods, so naturally it's convenient for me if landfills == good, but I also tend to wonder (a) exactly how effectively they isolate waste issues from, say, groundwater or other environmental circulation and (b) if there might be some volume threshold past which landfills aren't an adequate solution for addressing waste streams.
We are only now starting to measure up the microplastics impact and their origin. Switching to reusable cups is a drop in the ocean, when tons of the stuff is released by simply washing clothes or makeup off your face.
> wont be solved while big economies decide to export their waste
Western countries do not have proper regulations if one of the possible outcome for waste is to be exported where those regulations do not exist.
Last talked to him some time around 1998 but, you know, the logic was sound.
Which country(s) will own the machine?
Who will decide what we dial the CO2 back to? You'd think it would be back to pre-industrial times but who knows?
Will regions that have benefited from climate change and can now grow crops be on board? Or will they prefer to keep things as they are?