Concrete is a crucial substance for our humankind as you will see. However, concrete (or more exactly cement, one of its ingredients) is a major emitter of CO2, accounting for 8% of all CO2 emissions!
This week, we’ll start by exploring why concrete is such an important topic and how it is made in the first place.
Next week, we’ll continue by learning in more detail about cement production. Most excitingly, we’ll have an interview with a founder of a low-carbon cement startup!
I’ve again learnt a ton over the last weeks and am excited to share the learnings with you. Let’s go!
Humankind’s love - concrete
Concrete is a true wonder material. It is durable and can take practically any shape directly also at the construction site. Furthermore, concrete is relatively cheap and widely available around the world.
Our humankind has undoubtedly recognized the unique beneficial properties of concrete.
Already Romans loved concrete and built their constructs with it. (See the cover photo from Pantheon, Rome)
Aggregate like sand and gravel, contribute to the strength of the final concrete and add volume to the concrete mix. Aggregates also cost relatively little and so drive down the cost of concrete.
The downsides of our love for concrete
While concrete is an amazing material, we use it in such huge amounts that also its negative impacts are colossal.
1. CO2 emissions: 8% of the world’s total CO2 emissions
Cement production accounts for 8% of the world’s carbon dioxide emissions! To put this into context, if the cement industry was a country, it would rank as the third most CO2 emitting country after China and the USA.
Next week, we’ll go through in more detail how exactly cement production makes these emissions and how we can tackle them.
2. Freshwater usage
The sheer scale of concrete production also puts a strain on the freshwater supply.