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Stronger than aluminum, a heavily altered wood cools passively (arstechnica.com)
169 points by rbanffy on May 25, 2019 | hide | past | favorite | 57 comments


> But it gets better. The sugars in cellulose are effective emitters of infrared radiation, and they do so in two areas of the spectrum where none of our atmospheric gases is able to reabsorb it. The end result is that, if the treated wood absorbs some of the heat of a structure, wood can radiate it away so that it leaves the planet entirely.

This is the best bit. Put enough of this stuff on roofs and it can directly mitigate the greenhouse effect, by emitting IR that goes through the atmosphere and off into space.


I suspect roofs are about 0% of the Earth's surface.


It'd reduce energy consumption for air conditioning. Also, while rooftops are a small part of the global Earth surface (75% of it is not really a good place to put roofs on), the figure is much higher in cities and urban areas where, and it's not a coincidence, we spend a lot of energy keeping things cool.

Let's not forget cellulose is mostly made of CO2 removed from the atmosphere, which also helps a bit.

The only way it'd be better is if it were also a good material to build PV panels with.


It will not make much difference if it's reflected to space or not, though.


Of course it will. This is the idea behind space mirrors - reflecting 1% of sunlight is enough to completely counteract global warming. The radiation has to leave the atmosphere though.


No, this will not help.

Earth surface area: 510 000 000 km2

1% is 5 100 000 km2

I don't know how much this material reflects back, say it's 50%. So you need 10,2 mil. km2 to reflect back 1% of energy

Total USA land area 9,147,590 km2

You'd need to put roof over the entire USA with this material.

Also currently used materials also reflect something, so that would have to be accounted for, further increasing the needed area.


I don't know whether this will help or not, but your post seems to support the point of the commenter above, and make a good argument that it would help.

The comment said 1% would "completely counteract" climate change. You posit that we'd need to cover an area equal to that of the US to reach that 1%, which would mean covering a small % of that area would have roughly that level of positive impact. Am I extrapolating wrongly?


I'm saying you'll never get even close to 1% by putting this on roofs. Savings are nice, though.


You'd be lucky to cover 1% of the United States, much less 1% of the world. The real world impact of everyone in the US putting this on their roof would be minimal, and you're unlikely to actually get a significant percentage to switch anytime soon.

If you're looking for solutions to global warming, look elsewhere. However, that won't stop the marketing team from selling it as such. Evaluate this technology on its merits and take the IR radiation reflection as a bonus.


I guess my question here is: what's the lifecycle impact of producing this, and is the benefit zero or greater. Fair enough, covering 1% of the US land area would be a big ask, but a .1% positive impact on the climate is non-zero, and provided they're not looking for tax-incentives that could be spent on better things, it could well do no harm.


as far as reflection goes, whenever I see a satellite photo of Africa and I look at the bright, sandy Sahara Desert, I always wonder: does it help? or does it hurt?


It helps, which is why global warming scientists are concerned about the destruction of desert crust and so forth.


You should see it in infrared


ah! that would be interesting!


Climate vandals throwing pots of black paint on people's spacewood rooves with hacked amazon drones


Don’t climate vandals typically commit acts of vandalism to destroy things that harm the environment??


those are the whitehat climate vandals, I think...



I should have mentioned, it is my impression that this has as much or more to do with asphalt than rooftops, but anyway...


There was a company doing research on reflectors based on this. I wonder if progress has been made.


Yes, but they used a much more complex material, something like carbon nanotubes IIRC.


“the process involves dumping the wood in concentrated hydrogen peroxide and boiling it. While I wouldn't want to drink boiling, concentrated hydrogen peroxide, it's not an especially difficult chemical to handle safely.”

Diluted hydrogen peroxide is safe but in concentrated form it is one of the most dangerous substances. Early rocketry experiments used it as an oxidizer and it’s generally considered too unsafe.


https://yarchive.net/space/rocket/fuels/peroxide.html

While there are some storage headaches -- the stuff decomposes slowly no matter what you do, so you must provide for tank venting -- otherwise peroxide is much easier and safer to handle. Its bad reputation is half outright myth and half the result of 1940s experience with seriously impure peroxide. To quote a friend, a rocket-propulsion professional, who investigated the matter as part of a study some years ago:

"As far as we could find out, the stories about problems with peroxide were just that, stories... Peroxide, now, seems to only very rarely do anything exciting, at all. And, even then, it seems to never do many of the things attributed to it in the stories."

Henry Spencer


That would be this Henry Spencer: https://en.wikipedia.org/wiki/Henry_Spencer to bring in some hackish context.


I still remember Henry's contributions on comp.lang.c thirty years ago.


Thanks!



> Early rocketry experiments used it as an oxidizer and it’s generally considered too unsafe.

Wasn't Carmack's rocket company Armadillo Aerospace using hydrogen peroxide for the oxidizer?


They attempted to use it as a monoprop, where you pump it over a platinum screen to catalyze it. This is attractive because it avoids any issues with mixing.

They had extreme difficulty sourcing anything but dilute hydrogen peroxide. The few manufacturers refused to sell to them once they discovered the application. I think they ultimately bought a distillation unit made by a man involved in rocket powered drag racers in Mexico.

Ultimately, I think the higher specific impulse of fuel+oxidzer two part systems justified the added complexity and they abandoned monoprops.

As other's have noted, at 3% concentration hydrogen peroxide is pretty benign. At 60% it is quite dangerous. Armadillio Aerospace was exploring 90%+ concentrations.


Yep, that's how you "bleach" hair for hair dye. It's safe enough to put on your head, around your eyes... and heat for 15min before washing it out.


Not really: it's been used at least once on a satellite launch vehicle that made it to orbit: https://en.wikipedia.org/wiki/Black_Arrow


It's even more fun when mixed with sulfuric acid.


Or with acetone, on ice.


This is a lot like "transparent wood".[1] The lignin is removed as the first step. The transparent wood people put a clear polymer in.

[1] https://en.wikipedia.org/wiki/Transparent_wood_composites


Epic video by NileRed trying to make transparent wood https://www.youtube.com/watch?v=x1H-323d838


Thought of this when I read the article. Probably similar process.


I wonder how similar it is to Roechling's Lignoprotect bulletproof densified wood panels - https://www.roechling.com/industrial/products/composites/gfr...

edit - Since reading about densified wood, I have been wondering about if you can get paper to join to itself using pressure and the right chemicals. If so, you could form it into tubes by rolling it round a metal bar, and maybe even make the laminated paper bicycle from Gibson's Virtual Light.


Isn't that effectively the construction material for the ship Albatross in 'Robur the Conqueror' ?


Absolutely, yes. Paper compressed with an hydraulic press.


between this, and cellulose based frame material for construction and vehicles.. we may cross the CO2 emissions from a lot of industries off :)


"The researchers estimate that covering an apartment building with the treated wood could save about 35 percent of the energy used for cooling." Is that compared to the average building or a building covered with another kind of white plating? Because the latter would be super impressive while the former would mostly just state the obvious: white things don't heat up from sunlight as much as non-white things.


The difference between white and other colors is definitely not 35%. Less than 10% apparently for paints https://www.europhysicsnews.org/articles/epn/pdf/2007/01/epn...


> another kind of white plating

yes. e.g. commercially available white roof coatings which contain ceramic particles do a pretty good job of cooling a roof and reflecting sunlight.

but it's interesting that this treated wood radiates energy in frequencies that the atmosphere does not absorb


Agreed, it would also be very interested to see how this compares to other siding alternatives rather than simply wood vs treated wood (stucco, stone, steel, aluminum, vinyl etc.)


The challenge of lignin decomposition is why we have (most) coal.

https://www.nationalgeographic.com/science/phenomena/2016/01...


And cellulose it said, but suitable microbes have since evolved?


Is it still flammable though? I can't see anyone cladding an apartment building in flammable material, especially not after the Grenfell tower fire.


There are plenty of tall wooden buildings, some with wooden exteriors, some without. Wood doesn't actually burn all that rapidly, so it can be a safe choice in the right circumstances.

IIRC the biggest problem with the Grenfell cladding was the combination of flammable insulation + air cavity + flammable cladding. The cladding was not suitable to be used with that particular kind of insulation. Building codes are apparently pretty complex, but not without good reason.


It seems lignin actually has flame retardant properties, so unless they are adding some additional chemicals to make this wood fire resistant, it is probably even more flammable than normal wood.


Yeah, cellulose is highly flammable. That's why early film was so problematic


Well, the big reason early film is kind dangerous is that it was nitrocellulose, and so had plenty of nitro-groups just waiting to have a little fun...


Ah, my bad. Thank you for correcting me!


Wonder if this can be worked like normal wood and can be produced in the standard dimensions. One of the advantages of azek and other PVC sidings is that you can use your normal tools.


You can cut aluminum using woodworking tools if you need to. Assuming it's just for siding/roofing I see no reason a chop saw with an appropriate blade couldn't cut it.


Yeah, carbide blades will eat aluminum like butter. Just the other day I cut off a 3" x 3" slab of aluminum block with my table saw in 3/4" cuts. Wasn't sketchy, the saw didn't bog down at all, in fact ive cut woods that were far more difficult than that solid aluminum block.


How does its lifetime compare with ordinary wood? Does it rot easily?


I wonder if you can still cut and engrave it with a CO2 laser (10.6 µm). It might be a very interesting material to work with.




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