Making concrete blocks carbon zero

A lightweight aggregate made from unrecyclable plastic makes traditional concrete blocks net carbon neutral

Spotted: Concrete is the second most-used material on earth – only water is used by humanity more. Why does this matter? The cement industry that produces concrete is responsible for eight per cent of global carbon dioxide emissions. In fact, if concrete were a country, it would rank behind only China and the US in terms of carbon footprint.

What are our options for reducing the impact of concrete? Many solutions are focused on alternative materials or ways to strengthen concrete so that less is needed. But UK-based Low Carbon Materials is taking a different approach. Its solution is to make concrete blocks net carbon neutral by adding a carbon negative lightweight aggregate.

Sand and gravel are common aggregate materials, but Low Carbon Materials has developed its own aggregate called OSTO. This is made from otherwise unrecyclable plastic waste and is considered carbon negative because it ‘sucks in carbon from the atmosphere during the curing process.’

As OSTO makes up 10 per cent of a concrete block, the carbon it removes from the atmosphere offsets the carbon released during the production process, making the block as a whole carbon neutral.

OSTO is designed for use in medium-dense concrete blockwork, and the material is currently being trialled for imminent release into the UK market.

Other recent concrete innovations spotted by Springwise include a platform for digitising the concrete industry and concrete strengthened with used PPE and shrimp shells.

Written By: Matthew Hempstead