Concrete is a big contributor to climate change. Penn researchers say they can shrink its footprint | Concrete reabsorbs some of its carbon emissions over time. Alternative ingredients and 3D printing could help supercharge that by making the finished concrete more porous.

For context, [concrete production is responsible for ~8% of global emissions](https://en.wikipedia.org/wiki/Environmental_impact_of_concrete)

In general, the big issues with modified recipes for it and alternate designs for structures have been that architects and contractors don’t like taking risk with new things. This has made adoption of improvements painfully slow.