I recently spent some time digging into cement & concrete emissions, and they are FASCINATING
(apologies to all my friends who’ve had to hear about this at length)
#climatetwitter #energytwitter
(apologies to all my friends who’ve had to hear about this at length)
#climatetwitter #energytwitter
I should mention that I used to be a little obsessed with cement and concrete — I grew up next to a cement plant and won my school’s science fair with a project on strengths of different types of concrete — but I didn’t realize just how big their impact is
The current form of cement, Portland Cement, is the most common man-made material on the planet and it basically hasn’t changed at all in 200+ years
Cement has a carbon footprint THREE TIMES BIGGER THAN AVIATION. And if cement were its own country (Cementistan?) it would be the THIRD LARGEST EMITTER, behind only the US and China (!!!)
About half of these emissions come from chemical processes inherent to how we make cement, and the other half comes from the fossil fuels we use to MELT ROCK to 1,500 Fahrenheit to make cement
On the other end of the cement equation is concrete, which actually absorbs CO2 as part of its natural hardening process — and it absorbs a lot, around 50% of the CO2 that making cement emits. This lets us picture concrete as a potential carbon sink!
And all of this really matters because construction is booming—some estimates say that we’ll double the square footage of buildings in the next 40 years.
That means DOUBLING everything we’ve built over centuries over the next 4 decades—and we’ll need a lot more cement for that
That means DOUBLING everything we’ve built over centuries over the next 4 decades—and we’ll need a lot more cement for that
Fortunately, there are a lot of really smart people and awesome companies working in this space to decarbonize cement: @CSHub_MIT, @CarbonCure, @SolidiaCO2, CO2Concrete among them.
Lots of cool solutions, the challenge is deploying them within a slow-moving industry
Lots of cool solutions, the challenge is deploying them within a slow-moving industry
Anyways, thanks for coming to my TED talk!
