After water, concrete is the most widely used material on the planet. Favoured by engineers since Roman times, today roughly 30bn tonnes of concrete are poured worldwide each year—around three times as much per capita compared to 1980.
We need concrete. It remains vital for building infrastructure that can raise global living standards, but is alone responsible for at least 8 per cent of global carbon emissions, roughly the same as the total emissions from Africa and South America combined.
The scale of the challenge means that a fast-paced, targeted innovation drive is needed to reduce demand for new concrete by reusing buildings and utilising more recycled materials. In situations where using new concrete is unavoidable, we need to reduce emissions across the supply chain from mining, transport and processing, as well as through efficient design and construction.
The innovation is out there. We are seeing more of it—for example the impressive Boston Barrier flood protection scheme here in the UK. And it has the potential to help concrete become carbon neutral or even carbon negative, by capturing industrial emissions as a feedstock for concrete production.
But this innovation needs a deadline.
A clear timetable for reducing emissions will galvanise new collaborative efforts
A clear timetable for reducing emissions will galvanise new collaborative efforts, especially if blended with incentives that encourage the construction industry to change practices and adopt new technologies across a wide range of projects, from affordable housing to major infrastructure.
By 2030, these should include incentives for recycling concrete materials and reusing buildings over demolition. This could be done by removing VAT from refurbishment, for example, so there is a level playing field between refurbs and new builds which at present are exempt from VAT. We could also establish intelligent infrastructure procurement, to drive either this reuse and recycling or otherwise the use of low-carbon concrete. Finally, we need to see a blend of government investment and commercial incentives to create carbon capture pilots at cement works.
These are the first steps. But the deadline gives us the destination. Similar time-bound approaches have been used successfully to phase out energy-intensive lightbulbs, and to set an endpoint on combustion engines. Yet so far, by comparison, concrete remains a missed opportunity. This is despite a recent report by the Institution of Civil Engineers projecting that the UK’s concrete-related carbon emissions have the potential to be halved by 2035.
By providing key deadlines along the pathway to decarbonised concrete, we can drive engineering-led innovation in the UK, with knock-on benefits for the built environment worldwide. At the same time, we could give the construction industry the right balance of time and impetus to drive the changes we need to see.
This article first appeared in Minister for the future, a special report produced in association with Nesta.
