14 Comments

We can't eliminate all concrete use in construction, but we can replace part of it with mass timber, which has a much lighter carbon footprint. (See https://www.mdpi.com/2071-1050/14/1/144 )

Mass timber is rapidly growing in popularity in Europe, North America and Japan, and is now being explored in China as well.

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"We need innovations to eliminate CO2 production from the direct process itself."

Yes! Thankfully there are a host of great companies innovation on cement and concrete production. We need a wartime-level effort to scale these ASAP. But hope is on the horizon.

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Cement is needed for concrete which is needed for construction and at a cost of 4% of CO2 emissions seems like a reasonable price for civilization. As Vaclav Simil writes in his books, cement, fertilizer and other non-energy emissions are the hardest to reduce

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This article explores the environmental impact of China's cement production compared to the United States', highlighting the importance of sustainable practices in the cement industry for global climate efforts. See - https://augustagaconcretecontractor.com/

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Why compare 2020 to the 90s ? could easily use 2010-2020. May not get as many clicks though..

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Great post, but I'm struggling with the last figure. Are these just fuel-based emissions, rather than total emissions? The original data says fuel and process emissions for cement, but 1.6 billion tonnes of CO2 for 4.1 billion tonnes of cement is ~400kgCO2/tonne, which is about right for fuel use.

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I'm not sure what point you are making. "China makes a LOT of cement and that's bad for global warming" seems to be all I see. Am I missing something?

I write on the 'Climate Crisis" that's currently happening. I understand the importance of the point you are making because I think about infrastructure/CO2 levels/warming and how they intersect and affect each other. Cement and concrete are a "wicked problem" because our Anthroposphere (constructed world) is built on them.

Like oil, gas, coal, and steel they are the 19th century underpinnings to our 21st century world.

Consider “green concrete.”

As promising as a company like CarbiCrete may be, the niche it fills is a narrow one. Since it has to be cured in chambers filled with concentrated CO2, CarbiCrete can’t be poured at a work site. It can be used only for pre-cast products, such as cinder blocks or patio tiles.

Although the blocks and tiles absorb CO2 as they harden, a great deal of CO2 is released in the process of producing the slag that went into making them. The company uses the slag produced by the steel industry.

Globally, the steel industry is responsible for roughly the same number of tons of CO2 emissions as the concrete industry, roughly three billion.

Cleaning up one industry by using the waste products of another sounds good. But, if “carbicrete” became the new cement that leaves us still producing three billion tons of CO2 in order to make the slag we need for the carbicrete.

Which really means carbicrete is a "nonstarter". Because we also have to decarbonize the steel industry AT THE SAME TIME and the production of slag should fall to zero.

You also miss the geopolitical history behind China's massive surge in cement production, the Belt and Road project. China wants a secure supply line to Europe, the Middle East, and Africa. One that the US cannot interdict with our Navy. Building out the Belt and Road project is a matter of National Security for them. As well as a way of generating future economic growth the way the Interstate Highway Project (of similar carbon footprint BTW) did in the US.

We cannot demand the rest of the world not build highways and bridges until the steel and concrete problem is resolved. Not when we have "used up" the global "CARBON BUDGET". Not when the Average American is so "energy rich" and most of the world is "energy starved".

If you add up all the energy America uses in a year and you divide that by the total number of Americans, the result is per-capita consumption. The figure comes to about eighty thousand kilowatt hours.

Toss in the energy used to manufacture the goods imported into the U.S., and the Per Capita energy consumption for Americans rises to almost a hundred thousand kilowatt hours each.

To put this in terms of power, Americans EACH consume roughly eleven thousand watts every moment of every day. A string of incandescent Christmas lights uses about forty watts. It’s as if each of us had two hundred and seventy-five of these strings wrapped around our bodies, like the chains around Scrooge, burning 24/7.

This every-day-is-Christmas level of consumption,means that annual emissions in the U.S. run to sixteen metric tons of CO2 per person.

Americans don’t have the world’s highest per-capita emissions — that dubious honor goes to Kuwaitis and Qataris — but we’re up there.

Per-capita consumption in Thailand and Argentina runs to around two and a half thousand watts and emissions to around four tons.

Ugandans and Ethiopians use a hundred watts and emit a tenth of a ton.

Somalis consume a mere thirty watts and emit just ninety pounds.

This means that an American household of four is responsible for the same emissions as sixteen Argentinians, six hundred Ugandans, or a Somali village of sixteen hundred.

Now here’s the essential question. Are we going to build enough renewables in the next 20 years for everyone in the world to live like Americans currently do, or are American’s going to have to use less?

We waited until the very last minute to start and now we have to do “everything, everywhere, all at once”.

Because, if WE don’t do this All Together. We will ALL burn, Together.

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