Want Strong Concrete? Add Coffee



Ground coffee (photo by Kate St. John)

24 September 2023

A new study from Australia has found that adding used coffee grounds to concrete makes it 30% stronger!

Block of concrete (photo from Wikimedia Commons)

To prepare it for concrete, they collected already-used coffee grounds and turned them into biochar, using a low-energy process without oxygen at 350 degrees Celsius.

Use coffee grounds (photo by Kate St. John)

Not only did coffee make the concrete 30% stronger but this meant that the used grounds did not go to a landfill.

If the idea catches on, coffee will reduce the need for so much sand in concrete …

Portable concrete plant in Austin, TX (photo by Larry D. Moore via Wikimedia Commons)

… which will reduce the need to mine so much sand, a finite resource.

Sand mine (photo from Wikimedia Commons)

Will the piles of sand at concrete plants become piles of biochar coffee? Image it at Heidelburg Cement / Lindy Paving along the Parkway East near Uptown, satellite view below.

Google satellite view of Heidelburg Materials Concrete / Lindy Paving, 2nd Avenue, Pittsburgh

Read more about this innovation at Science Daily: Coffee Offers Performance Boost for Concrete.

I hope it catches on!

(credits in the captions)