This Is CDR is an ongoing series of online events to explore the range of carbon dioxide removal solutions that are currently in development. This week, we get a lesson from Chris Magwood about carbon sequestration in the build environment, which is to say, making our houses, stores, and other buildings not just lower in emissions but possibly even carbon negative.
In the vast sea of emissions reduction targets, we usually picture transportation emissions as the white whale, while buildings might sound like small fry. But in fact, as Chris points out, the production of building materials produces around 20 percent of all emissions. So even modern buildings that are more energy efficient once they’re built are likely to have produced a lot of carbon in the construction phase. The materials for building new American single-family homes alone produce 60 million tons of CO2 per year – the same as half a million cars or around 30 to 40 coal plants. (Which tells you a lot about coal plants, incidentally, but that’s another story.)
At the same time, there are a lot of potential building materials that right now are just getting thrown out (and then rotting and releasing their stored carbon back into the atmosphere). Agricultural residues like straw and barley are usually just left to decay in fields after we’ve taken the resources we need from them. As Chris notes, global grain production draws down four billion tons of CO2 every year – and most of it ends up right back into the atmosphere. Using that discarded straw as an insulation material, we could replace all new insulation on the planet and still have straw to spare.
Meanwhile, as you may be aware if you’re following OpenAir, concrete production is a huge source of carbon emissions. We’ve worked to address this with LECCLA in New York, but according to Chris, low-emission concrete is just getting started. Researchers are experimenting with using microbes or algae to generate carbon-negative biocement, and even making synthetic limestone by capturing CO2 from smokestacks and remineralizing it into rock. Chris’s talk is full of fascinating possibilities like these – many of which are very close to or even already in production – so we really encourage you to check it out. Thanks for watching – be sure to check back next week for more This Is CDR, and check out the whole series on our resources page.