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A CO2 capture solvent with exceptionally low total costs of capture

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Re: A CO2 capture solvent with exceptionally low total costs of capture

#221

Earlier quoted context omitted.

In my experience, the obsession with correct significant figures is an american high school thing. Why should you deliberately have to choose a number that is not your best guess? Ideally you should include confidence bounds, but if you don't, it shouldn't imply that you are confident to that level.

When I was getting my engineering degree too many significant figures would earn you -2 pts.

Measure with a micrometer.

Mark with a chalk.

Cut with an axe.

(Apparent practice at a workshop I used to frequent.)

Re: A CO2 capture solvent with exceptionally low total costs of capture

#222
post #201

Earlier quoted context omitted.

Would you get enough salmon to offset the cost? What’s the net cost of this approach?

I wouldn't count on any savings from the $1.5B. You would get more salmon than we know what to do with and you have to harvest them or the overpopulation would mess with the ecosystem.

> more salmon than we know what to do with

Bury them in the ground as fertilizer?

Requires people to fish them up, but maybe we can redirect some of the effort that goes into overfishing to that.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#223
post #210

Earlier quoted context omitted.

Because it gives an idea of what range is expected for the actual price. If someone gets an estimate of "about fifty bucks" versus "about $51.04", their reaction to seeing a final price of say $62.17 would be different. The first one implies that it's a rough estimate, while the second one doesn't.

If someone said "about fifty bucks" and it turns out to be $62.17, I'd immediately understand them to be scamming me.

Really depends on what the context is. Maybe for a taxi ride when negotiating a price ahead of time, but pointing at an object, asking for its price, getting an estimate that's off, then getting the actual price before the transaction is completed doesn't feel like a scam.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#224
post #221

Earlier quoted context omitted.

When I was getting my engineering degree too many significant figures would earn you -2 pts.

Measure with a micrometer. Mark with a chalk. Cut with an axe. (Apparent practice at a workshop I used to frequent.)

Old crusty semi-retired engineer I knew said when he was young he liked designing things to close tolerances. But once he was old he found more pleasure in designing things that worked with really shitty tolerances.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#226
post #221

Earlier quoted context omitted.

Measure with a micrometer. Mark with a chalk. Cut with an axe. (Apparent practice at a workshop I used to frequent.)

Old crusty semi-retired engineer I knew said when he was young he liked designing things to close tolerances. But once he was old he found more pleasure in designing things that worked with really shitty tolerances.

-I had a colleague once, fresh out of mechanical engineering at the local univerity college, who as his first project did a locking pawl for a winch drum.

Tolerance? H7.

The fitters threw a fit trying to make that happen.

Re: A CO2 capture solvent with exceptionally low total costs of capture

#229

Earlier quoted context omitted.

It is still suspicious to use so exact numbers for a technology that has not yet been tested out at scale at all.

In my experience, the obsession with correct significant figures is an american high school thing. Why should you deliberately have to choose a number that is not your best guess? Ideally you should include confidence bounds, but if you don't, it shouldn't imply that you are confident to that level.

It hints that someone doesn’t understand these confidence values at all.

Why $47.10 and not $47.1032471?

Re: A CO2 capture solvent with exceptionally low total costs of capture

#230
Every time something like this comes up I think exactly the same thing: Did everyone flunk first year Physics?

Someone please explain how nobody seems to care about the fact that you cannot violate conservation of energy.

How much energy will it take to reduce atmospheric CO2 by 100 ppm?

Never mind time and resources. Let's just talk energy.

How much?

The simple answer is: More than the energy that went into creating the problem in the first place.

How much more?

A lot more. Because these processes are not efficient at all when looked into in their entirety.

A number?

OK. How did we get the CO2? By burning oil. What did it take to create this oil. Billions of years of plants and biological matter being crushed and cooked by...solar energy. Massive amounts of energy falling on this planet. The end result being a highly concentrated source of energy. When we burn a gallon of oil we are releasing the culmination of what took unimaginable time and energy to produce.

You are not going to make an impact without expending an equally massive amount of energy and resources.

Let's say I burn a pile of lumber inside a large sealed warehouse. Say, 100K square feet (about 10K square meters) and very high. Large volume. Smoke, particles, gases disperse throughout the volume.

You are tasked with cleaning it.

You can't open windows, etc. That would be cheating. There is not "and then a miracle occurs" scenario.

It would take an immense amount of energy and resources (relative to what it took to create the mess) to go find every particle and clean-up the noxious gases in that warehouse.

If we can't clean a warehouse, what makes anyone think we can magically deal with a planetary-scale problem?

We already know this. There are research papers that explain just how it is that even the idea of converting the entire planet to renewable energy sources is an exercise in futility.

My point is: If we could just stop lying to ourselves maybe we can devote brain power towards dealing with the reality of the problem rather than the fantasies of non-existing solutions.

I am not saying "let's be filthy and do nothing". I am simply saying we are not facing reality, which means we are wasting valuable time and resources "solving" a problem we cannot possibly solve without risking killing everything on this planet.

All you need in order to understand this is the atmospheric CO2 data from ice core samples going back 800,000 years. We know that if humanity was not around it would take about 50K years for a 100 ppm drop in CO2. In other words, with the ultimate "solution" --if we left this planet-- it would take 50K years. What makes people actually believe we can solve the problem in a generation or two if we stick around? That's not hubris, that's a delusion. Sorry.

If anyone disagrees. Great. I would like to learn how I am wrong. Kindly explain how you are going to achieve a rate of change between 500 and 1,000 times greater than what could be achieved if humanity --and all of our technology-- got erased from this planet. That's the challenge. No magical technology can do better than the absence of humanity and all of our toys. That should be self evident. And yet, without us around, the timeline is in the 50K year range.

Take your time, show how this 1000x improvement in rate-of-change will happen without at least 1000x the energy deployed at a planetary scale by natural processes.

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