Buildings could store half of humanity’s carbon dioxide emissions, says a new study

If in construction, we would switch to using carbon-storing materials, we would take a big leap towards carbon neutrality.

As much as half of the amount of carbon dioxide that humanity releases into the air in the same period of time could be packed into houses, roads and other structures.

This is what an American article published in the journal Science on Thursday evening says research.

In buildings, carbon dioxide remains stored for a long time and does not escape to warm the climate.

It is possible to add carbon to at least concrete, asphalt and brick. Wood and bioplastic contain a lot of carbon anyway.

Researchers at the University of California calculated that with these materials it would be possible to capture a total of about 16 gigatons of carbon per year in new buildings – half the amount of carbon dioxide that humanity released into the air in 2021.

Building materials efficiency as a carbon storage is due to the huge amount of construction in the world, according to the research report.

It is also intuitively clear, says the former specialist researcher at VTT Tapio Vehmaswho has studied the binding of carbon dioxide in concrete for a long time.

“It’s nice that the huge potential has been calculated,” he says.

Until now, more thought has been given to the geological storage of carbon dioxide in, for example, depleted natural gas and oil fields.

“The built environment is a good alternative to geological storage, because humanity is building all the time anyway,” says Vehmas.

Vehmas now works as the CEO of Carbonaide, a company born on the basis of VTT’s research, which has started manufacturing carbon-storing concrete products in Hollola.

the material According to the study, the potential for coal storage depends most on the amount of material produced.

By far the greatest possibilities are offered by concrete. According to the study, it could store the vast majority of all the carbon that can fit in buildings, because concrete is used so much.

The coal to be packaged can be biochar or carbon dioxide captured from the ends of chimneys and from the air.

Biochar can be used to replace fine aggregate in concrete.

In the Finnish Carbonaide method, the cement contained in concrete is replaced with carbon dioxide.

Cement has a tendency to bind carbon dioxide, but the binding stops when the concrete has hardened. More carbon is added to the concrete by treating the concrete with carbon dioxide in the hardening state.

In the manufacture of cement, we would also have to switch to low-emission methods, because a very large amount of carbon dioxide is released in the traditional production method.

Practically the greatest impact on the climate is achieved by those materials that are in the best position to take over the market and whose production can be quickly increased, the research report states. Many companies are only in the pilot phase.

According to Vehmaa, the production of carbon-storing concrete is also undeveloped.

“We know 10–15 start-up companies that operate in the field. The expectations are huge, but the investments are small so far.”

Carbon binding raw materials are not necessarily easily available either.

Wooden construction is a big thing in Finland, but globally its potential is small, according to the researchers’ calculations.

Competition can arise from biomass when it is wanted to be used for more and more purposes. The arable land required for biomass production is also needed for growing food.