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Cement is the source of 8% of the world's CO2 emissions (2018)

bbc.com

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Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#61

Post by vixen99 »

akira2501 wrote: post #12
aero-glide wrote: post #4

Very interesting, didn't expect it to be that high. Another thing I came across recently : The fashion industry is responsible for 10 % of annual global carbon emissions. Source : https://www.worldbank.org/en/news/feature/2019/09/23/costo-m...

That was my biggest take away from the Biosphere documentary, as it was the concrete used in it's construction that eventually led to the abundance of CO2 and lack of O2 in that closed system. We'll clearly have to use something else for building moon bases.

Sorry for the tangential drift but it's ubiquitous now. I guess those boring grammar pedants should finally give up. The totally meaningless and incorrect apostrophe in it's (unless it indicates an abbreviation) has gone viral. You can even find it in headlines in newspapers. Odd really that many of us go to the trouble of adding a pointless character intent as we are on writing correct English. I think we should keep on trying though.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#62

Post by burntoutfire »

thinkloop wrote: post #11
aero-glide wrote: post #4

Very interesting, didn't expect it to be that high. Another thing I came across recently : The fashion industry is responsible for 10 % of annual global carbon emissions. Source : https://www.worldbank.org/en/news/feature/2019/09/23/costo-m...

So the biggest polluters are food, clothing and shelter - I'm seeing a pattern here...

Clothes industry has long stopped being about clothing and moved to stroking egos instead (infinite stream of money in that). It is even reflected in the name change ("clothing" -> "fashion").

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#63

Post by takeda »

throwaway698 wrote: post #52
manfredo wrote: post #26

Earlier quoted context omitted.

Statistics on how much CO2 something emits can vary wildly. For instance, meat consumption has high CO2 emissions when you include the CO2 emitted by transporting grain to feed animals. But most typical studies would include that under emissions due to transportation. Hence why you can have some studies claiming meat accounts for a double-digit percentage of emissions while others claim that all agriculture contribut…

About meat specifically -- one has to be careful when counting all greenhouse gases versus just CO2, and pure quantity of gas vs. effect on global warming. Cattle produces a lot of methane, which has a very powerful greenhouse effect, a lot more powerful than CO2. So while it does not contribute to CO2 emissions that much, it contributes to the greenhouse effect proportionally a lot more.

Oh yeah, I remeber also driving once next to a large farm with cows, it's crazy how much of the gas they produce.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#64

Post by dsirola »

throwaway698 wrote: post #52
manfredo wrote: post #26

Earlier quoted context omitted.

Statistics on how much CO2 something emits can vary wildly. For instance, meat consumption has high CO2 emissions when you include the CO2 emitted by transporting grain to feed animals. But most typical studies would include that under emissions due to transportation. Hence why you can have some studies claiming meat accounts for a double-digit percentage of emissions while others claim that all agriculture contribut…

About meat specifically -- one has to be careful when counting all greenhouse gases versus just CO2, and pure quantity of gas vs. effect on global warming. Cattle produces a lot of methane, which has a very powerful greenhouse effect, a lot more powerful than CO2. So while it does not contribute to CO2 emissions that much, it contributes to the greenhouse effect proportionally a lot more.

The methane has lower cumulative impact and is a closed loop where it gets recycled over time. [1]

[1] https://onezero.medium.com/cow-farts-are-not-the-problem-f57...

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#65

Post by teruakohatu »

BossingAround wrote: post #29
Pfhreak wrote: post #15

Earlier quoted context omitted.

Garments that are high quality are designed to last and be worn for a long time. High end selvedge jeans might run a couple hundred bucks, but they will last a decade. I suspect cheap, disposable clothing is driving much more emissions.

> High end selvedge jeans might run a couple hundred bucks, but they will last a decade. Is there any data supporting this? Because while I think this is our intuition, i.e. "it's expensive therefore it's better quality," I wonder if there's any way we could verify this other than anecdotal evidence.

You see the British aristocracy wearing 30+ year old shoes that look as good or better than they did when they were new.

I think it is common sense that emissions are far lower for extreme-luxury clothing that can be repaired and is timeless verses disposable clothing that last one or two years.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#66

Post by jillesvangurp »

ehou wrote: post #23

The article doesn't mention one alternative: CLT (cross laminated timber) as a building material for houses and flats. See https://www.bbc.com/future/article/20190717-climate-change-w... for example. Using CLT (and passive house principles) can reduce the total CO2 emmissions of a house by 90% in its total life span. The wood in CLT stores carbon and the passive house principles reduces energy needs.

Yes. And better than that using this at scale is going to require massively scaling up wood production (i.e. forestry). This too will help with capturing a lot of co2 in the soil. A lot of countries would end up restoring farm land to production forests and probably end up using sustainable practices for this.

For those unfamiliar with CLT, this is a high tech building material suitable for making e.g. sky scrapers or other types of buildings. It's much lighter and stronger than concrete. Because it is lighter, you save a lot of fuel transporting it. It's fire resistant and rot resistant because it is chemically treated. It's also much easier to work with as you can drill, glue, saw, etc. it. Additionally, you can do this off site meaning actual onsite construction activities are a lot more straight forward, less noisy, and much less wasteful. Think Ikea for buildings.

To sketch you a picture of how awesome this stuff is, the Japanese are planning to build a 1100 feet skyscraper made of wood, steel, and clt in Tokyo, which is of course a city that regularly sees earthquakes and tropical storms. https://www.archdaily.com/889142/japan-plans-for-supertall-w....

The biggest challenge is going to be simply scaling the production of this material and transitioning the construction industry to mostly using this instead of concrete. Right now it's kind of a novelty / niche thing and it is going to take a while to reach efficiencies and economies of scale we have with concrete today. It's not exactly cheap (yet) but it could become cheaper long term; especially if you consider all the benefits (technical and environmental).

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#67

Post by teruakohatu »

hinkley wrote: post #32

I was looking for brick pavers recently and was having quite a time locating actual bricks instead of cement pavers colored badly and textured worse to look vaguely like bricks to nobody sober during daylight hours. I can only assume their target audience is a drunken man, at night, in a rainstorm. I have to wonder why we are still looking for new ways to employ Portland cement at this point, over alternatives. You c…

> I was looking for brick pavers recently and was having quite a time locating actual bricks

I am not an American but I am not sure I have even seen a paver made from brick now that I think about it. I suspect the larger a brick is, the more chance of cracking.

So if it makes you feel any better, you probably would not find one in New Zealand either.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#68

Post by shortercode »

The largest issue with concrete is that we misuse it. As a building material it has great thermal mass ( aiding temperature stability ) and longevity. But all too often buildings are poorly designed for renovation, and hence end up being torn down after a couple of decades. A small fraction of the useful lifetime of the structure. Any building using concrete for a structure should be aiming to last at least 100 years.

For those who didn't read the article: the chemistry of Portland cement works against it. Production requires heating the calcium carbonate to a high temperature to extract carbon dioxide from it. Which obviously produces large amounts of CO2 proportional to concrete production. However, concrete also absorbs carbon dioxide from the air over its lifetime. So the measured emissions aren't the entire story.

Perhaps in future we will consider this an excellent source of carbon dioxide for the production of various hydrocarbons. I've heard of several efforts to create octane using carbon dioxide from the air, but you need a large amount of energy to extract a useful amount of CO2. Well this would be a good source of high concentration CO2. Perhaps not for octane ( we should really be moving away from combustion engines ) but perhaps plastics and other products that are currently derived from crude oil.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#69

Post by anonymfus »

stanmancan wrote: post #21
treve wrote: post #14

Earlier quoted context omitted.

I don't have the answer, but I can imagine this is hard to compile because so many things emit CO2 all over their supply chain. So the question becomes, when do you consider something the 'final' product in the line. If it's cement, you presumably can't count 'construction' as it would be double-counted. Do you count an iPhone just during production? Or do you include shipping? If you include shipping, you can't have…

I would argue cargo ships don’t need their own category in that case since they don’t exist for any other reason than to be part of the supply chain or other goods. All cargo ship pollution can be attributed to the cargo they’re transporting.

But ultimately the main purpose of such stat is to make policy decisions to reduce amount of greenhouse emissions, and so it should show effects of the both making cargo ships more emmision efficient and reducing amount of things people buy. So it's better to let it overlap.

Re: Cement is the source of 8% of the world's CO2 emissions (2018)

#70

Post by jmiskovic »

shortercode wrote: post #68

The largest issue with concrete is that we misuse it. As a building material it has great thermal mass ( aiding temperature stability ) and longevity. But all too often buildings are poorly designed for renovation, and hence end up being torn down after a couple of decades. A small fraction of the useful lifetime of the structure. Any building using concrete for a structure should be aiming to last at least 100 years…

Do we want 100 year old buildings? I don't think we can predict the needs of building even 20 years into the future. City layout could change drastically. Monumental buildings should last a long time, but not every structure.

The alternative is to build from wood whenever possible, and capture extra cabon in building material. This increases market need for wood and therefore forestation.

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