The big problem with cement, and how to fix it

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I have worked a lot in this industry and can say that this video is very correct, they included pretty much everything in modern cement industry carbon reduction. However it should be mentioned that there is also a large natural difference in cement produced in different countries due to different properties in local materials. Also the "just use wood" is mostly marketing/lobbying from the wood industry. If we used as much wood as we did cement there would be no forests in just a few decades.

I finally know why cement trucks are not called concrete trucks!

I believe all these companies and countries that are saying net zero by 2030 are going to keep pushing that date further and further into the future

Another issue with cement/concrete is that it tends to trap heat and slowly release it back to the surroundings even at night, which contributes to higher ambient temperatures in urban environments. This contributes to what is known as the "Urban Heat Island" effect.

Thank you for pointing out the importance of correct cement use in earthquakes, we suffered from that a lot in Turkey

One big thing that wasn't mentioned is using concrete with high-tech additives like a small fraction of chopped glass or plastic fibers and even graphene to make it much stronger so you need less concrete and steel to make the same structure. There are other advanced techniques like foamed concrete that can reduce the weight, especially for floors where bending strength is the most important factor. As for fueling the cement-making process, I feel like there are a few net-zero options that should have been mentioned. The obvious one is green hydrogen, which can clearly reach the required temperatures without carbon emissions. As for electrification, electric arc furnaces like the ones used in steelmaking can easily reach the required temperatures, so it's not necessarily easy, but it's a solved problem. The other thing I wonder is why they wouldn't mention biomass to heat the kiln, since fly ash can replace some of the cement and you can get usable fly ash on site from biomass once everyone stops burning coal, which is the current source.

This video seems to be released in tandem with Veritasium's video about cement. I'd like to think that these two videos explain two sides of the same story. Veritasium explaining the amazingness of concrete and how good it is, and this video explaining the side effects that we are experiencing due to our reliance on it. Overall, both are a good watch. Never just trust one source after all.

Thanks for using the metric system and Celsius. So all the world can understand it.

Another thing we have to be weary of when making concrete is sand. The world is starting to run out of the type of sand used in concrete and we should probably start looking for alternatives.

Despite the carbon emissions of concrete, would high-density housing in concrete skyscrapers be better than low-density urban sprawl? Considering the costs of building and maintaining roads and utilities, and the costs of transportation (public/private), maybe a single concrete apartment is better than an equivalent number of wooden houses just by the fact that everything is much closer together.

I’m a civil engineer and living in the Caribbean is very difficult to build without concrete with the amount of hurricanes We receive and with time those forces are getting stronger. Steel construction here could be done but it’s maintenance is expensive do to all the exposure to the sea. There are lots of places you can build without concrete but not the caribbean for now

Recycled concrete could also be added to the equation.

This video is why I love Vox. You guys make great videos and articles by asking questions we probably would never ask ourselves. Then you introduce the topic well and build on it perfectly. I always learn something new here.

As a final year Civil Engineering student I loved this episode😌

Συγχαρητήρια Χριστίνα χάρηκα που είδα Ελληνίδα στο vox και για αυτό προφανώς ευθύνεται η ποιοτητα της δουλειάς σου. Για άτομα σαν εσενα θα έπρεπε να υπερηφανευόμαστε 👌

Thank you for discussing this very important topic but I wish you mentioned the devastating local environmental effects of sand mines and how our world (believe it or not) is quickly running out of viable sand

Hi there! I am a graduate architecture student and we are currently studying Hempcrete. I think it would be wonderful for you guys to cover this topic on a sustainable substitute! Our class would gladly share all of our research and experiments with you all at Vox!

Thank you for this kind of videos. We know that there are a lot more things wasn't discussed here due to time constraint, but the idea was captured, to introduce the possibility that it can be lessen. Good video overall. 👌

Carbon capture is such a weird technology. It barely seems to work in real life, but on paper is a good idea. As well it seems a like a bandaid solution for a mass trauma situation, more can be done by just planting trees to recapture carbon( u could also technically do this with cement although I wouldn’t rlly know how to). Overall tho cool to say our people(humans) innovate and find different ways to make our plant a better world.