Newsroom
What if your daily cup of coffee did more than fuel your morning? What if it also helped build stronger, greener cities? Australian researchers have uncovered a groundbreaking way to transform coffee grounds into a material that makes concrete up to 30% stronger, offering a clever solution to two global problems: coffee waste and the construction industry’s demand for resources.
Every year, around 22 billion pounds of coffee waste ends up in landfills, emitting harmful greenhouse gases like methane and carbon dioxide that contribute to climate change. At the same time, the booming construction industry’s hunger for concrete is driving the unsustainable mining of sand, damaging ecosystems and depleting a finite resource.
Imagine sipping your morning coffee, knowing its leftover grounds could one day help construct homes, schools, and cities.
"Disposing of organic waste is a major environmental challenge," said Rajeev Roychand, an engineer at RMIT University. "But with a circular-economy approach, we can keep waste out of landfills and better preserve natural resources like sand."
Raw coffee grounds can’t be added directly to concrete because they release chemicals that weaken the material. The researchers overcame this by using a process called pyrolyzing—heating the coffee grounds to 350°C (about 660°F) in an oxygen-free environment. This creates biochar, a carbon-rich, porous material that bonds well with cement, enhancing its strength.
The researchers found that heating coffee grounds to higher temperatures, like 500°C, produced weaker biochar, proving that the right balance is crucial.
While this coffee-infused concrete shows great promise, further testing is needed to ensure it stands up to challenges like harsh weather, water absorption, and wear and tear. The team is also exploring biochar from other organic waste, such as food scraps and agricultural residues, to expand the concept’s potential.
"This research is about creating sustainable cycles for materials and minimizing waste," said researcher Shannon Kilmartin-Lynch, who emphasized the importance of balancing innovation with environmental care.
Imagine sipping your morning coffee, knowing its leftover grounds could one day help construct homes, schools, and cities. This innovation redefines waste as a valuable resource, turning one of the world’s most discarded materials into a cornerstone of sustainable construction.
The findings, published in the Journal of Cleaner Production, hint at a future where our smallest habits—like making coffee—could have a big impact on building a better world.
