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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

#231

Post by silasdavis »

labster wrote: post #203
petra wrote: post #199

Earlier quoted context omitted.

It's not enough to change people's beliefs about climate change and political choices. >> Olivine is plentiful, everywhere, That means olivine will be mined everywhere. not necessarily in coal country.

Computers are plentiful everywhere, yet more bits are mined in SV than anywhere else. Maybe the fact that bit mining expertise is concentrated there is useful to produce more zeroes and ones. I suppose the same might be true of olivine.

> yet more bits are mined in SV than anywhere else

Are they?

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

#232

Post by LasEspuelas »

nullc wrote: post #208
phreeza wrote: post #196

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.

Yep. The weird thing is that their sigfig rules of thumb aren't particularly accurate and after any non-trivial operations (or more than a few operations) just give wrong results. Tracking precision through calculations requires interval arithmetic, which is a pretty big PITA and not frequently used. I think the sig figs cult comes out of mistaking a simplified lesson on precision for a useful practice.

Not sure exactly what you mean. It is well known that you should keep additional digits throughout the calculation and then drop non-significant ones for final results.

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

#233

Post by occz »

fnord77 wrote: post #174
TigeriusKirk wrote: post #131

Earlier quoted context omitted.

>I think we should really reduce our energy usage instead. There is no viable future scenario in which mankind's energy usage decreases. It's a pipe dream, and ultimately a dangerous one. Energy use is fundamentally tied to progress to such an extent that we should always be looking for ways to increase the energy available to us. Of course the energy should be produced in as low-impact a manner as possible, but it's…

> There is no viable future scenario in which mankind's energy usage decreases sure there is. reduce the population by a factor of 10.

Any true malthusian will of course voluntarily take the first step and remove themselves. Right?

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

#234

Post by api »

occz wrote: post #233
fnord77 wrote: post #174

Earlier quoted context omitted.

> There is no viable future scenario in which mankind's energy usage decreases sure there is. reduce the population by a factor of 10.

Any true malthusian will of course voluntarily take the first step and remove themselves. Right?

Scratch a Malthusian and you will find either a pure misanthrope or a racist. In either case the solution is always for others to die.

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

#235

Post by aaron695 »

CharlesW wrote: post #163
londons_explore wrote: post #40

Earlier quoted context omitted.

$47.10 per ton smells like someone has calculated the cost of the reagents and cited that as the price... Any estimate of this process cost would never be to 3 Sig fig.

I don't know why $47.10 is any less credible than $47, but here's more detail on what the estimate represents from TFAMA: "For the $47.10/metric ton carbon capture cost, 48% comes from CAPEX while the remaining is OPEX. The equipment life of a carbon capture unit would be similar to that of a power plant, about 20-30 years. The $47.10/metric ton cost is just for carbon capture, and does not include transportation and…

> I don't know why $47.10 is any less credible than $47

It shows a lack of understanding of either basic science or napkin maths.

For either reality, science or invention, it matters.

https://en.m.wikipedia.org/wiki/Significant_figures

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

#236

Post by Scipio_Afri »

jfim wrote: post #223
throwawayfire wrote: post #219

Earlier quoted context omitted.

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.

Please price estimates for car repairs in dollars and cents and state it's only an estimate all the time.. with variations possible depending on what's discovered that might have been missed it that particular context.

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

#237

Post by xyzzy21 »

What's the energy consumption to make this moderately complex organic compound? If it takes more energy (largely generated from fossil fuels - and generating CO2 itself) than it removes... it's not going to be viable. You must have >1:1 otherwise you are better off doing nothing at all.

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

#238

Post by [deleted] »

aaron695 wrote: post #235
CharlesW wrote: post #163

Earlier quoted context omitted.

I don't know why $47.10 is any less credible than $47, but here's more detail on what the estimate represents from TFAMA: "For the $47.10/metric ton carbon capture cost, 48% comes from CAPEX while the remaining is OPEX. The equipment life of a carbon capture unit would be similar to that of a power plant, about 20-30 years. The $47.10/metric ton cost is just for carbon capture, and does not include transportation and…

> I don't know why $47.10 is any less credible than $47 It shows a lack of understanding of either basic science or napkin maths. For either reality, science or invention, it matters. https://en.m.wikipedia.org/wiki/Significant_figures

[deleted]

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

#240

Post by ytpete »

sbierwagen wrote: post #216
worldofmatthew wrote: post #204

Earlier quoted context omitted.

I am pretty sure the $0.10 per tree of the Eden reforest project would be far cheaper than $47.10 per ton, to say the least. That would be 471 trees for $47.10.

Reforestation only sequesters carbon if the land remains forest forever. If it’s cleared again in the future then that carbon goes right back into the atmosphere.

Doesn't it depend on what is done with all the wood that was chopped down? If used say for construction, that carbon is staying out of the atmosphere.

Or do mature trees not make up the majority of the carbon that is stored in forests?

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