“The road to success is always under construction.”
Lily Tomlin
This week I learned that the number two most-used substance in the world (after water) is cement. That was not on my bingo card. And this is problematic for our climate, because the process of making cement uses a lot of energy, and also emits carbon dioxide into the atmosphere. So to solve climate change, we need a concrete plan for lowering emissions.
During my research, I also learned that cement and concrete are not the same thing. Bob Vila gives a great analogy to explain the difference. Cement is to concrete as milk is to ice cream. In other words, cement is an ingredient of concrete, but concrete is better. Concrete is stronger and more durable, and for that reason, it is used on most construction projects – from commercial buildings to bridges, roads, and tunnels. So we need them both.
A few facts about cement
- Cement is needed to make concrete
- The process of making cement uses lots of energy and water
- The production process creates CO2 emissions as a byproduct
- 8% of the world’s CO2 emissions come from the cement industry
- As an industry, cement is the second-largest emitter of CO2
A concrete plan
It’s fair to say concrete has built our modern society, and is vital to our economy. So it’s not going away. But what if there was a way to make cement with fewer harmful emissions?
It turns out there are several ways. Although not widely commercialized yet, alternative materials like industrial waste and natural materials can be used to make cement without all the CO2 emissions. These materials are readily available and cost-effective. Also, an international research group has found a way to make cement by combining geopolymers with natural fibers and waste products. Reusing waste products also keeps them out of landfills. Win-win.
Another strategy for reducing emissions is to capture the CO2 during the production process, and inject it back into the concrete. It will then stay embedded in the finished product rather than going into the atmosphere.
What can we do?
If you are planning a construction project, ask your contractor about low-carbon concrete. Innovation and change are driven by demand, so the more people are asking for more lower-emission products, the faster they will become available.
Let’s do something about climate change. Learn about it. Think about it. Talk about it.