Morning coffees make greener concrete in Australia

STORY: Your morning cup of coffee could help the planet.

:: Melbourne, Australia

That's the promise of one Australian university that's transforming used coffee grounds into more sustainable concrete.

They say the process could potentially lower greenhouse gas emissions.

:: Sustainable Business

The researchers at RMIT University are heating the coffee grounds to over 650 degrees Fahrenheit in an oxygen-free chamber to create a substance called biochar.

They claim biochar can replace up to 15% of the sand used in concrete and make it 30% stronger.

:: Rajeev Roychand, Lead researcher

"And we can leverage that to even reduce the cement content which is a highly carbon-intensive material."

Rajeev Roychand is the lead researcher.

"We anticipate that the whole 100 percent of coffee waste in Australia can be recycled into concrete applications."

Concrete production is responsible for around 7% of the world's CO2 emissions, according to the United Nations.

Over 55 billion tons of sand and gravel are dug up each year, mostly for use in concrete.

Its extraction is often environmentally destructive and the UN says it's in increasingly short supply.

This footpath was successfully made with coffee concrete.

The researchers here are working with several construction and concrete companies - and forming their own biochar company.

They're also in talks with Starbucks to take its coffee grounds.

Local coffee shop owner Tony Roussos says he would get in on the action too.

:: Tony Roussos, Owner, Degraves Espresso Melbourne

"Fantastic, it's a very innovative idea. Bring the cost of concrete down and the materials, obviously there's a benefit to the environment for not using harsh chemicals and replacing it with coffee grounds which is a natural product, easy to access, a lot of cafes could sell their coffee grounds so end to end it's a great solution."

Roychand says that eventually the technology could be used for more than just coffee.

"In terms of real-world our focus is that we try to transform all of the organic waste that is ending up in landfills for this positive application in concrete so we anticipate that 60 to 70 percent we can divert from landfills in concrete applications."