Scientists Turn Coffee Waste Into Valuable Clean Energy Source

Every day, millions of cups of coffee are brewed, enjoyed, and then forgotten. What remains is a pile of damp coffee grounds—waste that usually ends up in the trash. At Teuku Umar University (UTU) in Aceh, Indonesia, however, a team of researchers saw something different. They saw potential.

Driven by the idea that waste could become a valuable resource, three lecturers from UTU's Faculty of Agriculture—Utari Azrani, Muhammad Reza Aulia, and Fantashir Awwal Fuqara—developed an innovative method to transform spent coffee grounds into solid fuel briquettes. Their work has now been officially recognized with a Simple Patent Certificate issued by Indonesia's Ministry of Law, marking an important milestone in sustainable energy research.

The journey began with a common problem. Coffee-ground briquettes had been produced before, but their quality was often inconsistent because the manufacturing process lacked clear standards. Some burned too quickly, others produced too much smoke, and many failed to deliver reliable heat.

Rather than accepting these shortcomings, the research team designed a method that carefully controls every stage of production.

Fresh coffee grounds are first collected from coffee machines and dried until their moisture content reaches an ideal level. They are then blended with tapioca flour, which serves as a natural binder, along with fine sawdust and measured amounts of water to create a uniform mixture.

The mixture is compressed using a hydraulic press, producing briquettes with a carefully controlled density. Finally, the briquettes are dried in an oven at temperatures between 80 and 100 degrees Celsius for several hours until their moisture content falls below ten percent. This precise process ensures a cleaner, more efficient, and more stable fuel.

For Utari Azrani, the innovation is about far more than creating a better briquette.

"Our goal was to develop a method that communities could easily adopt," she explained. "It offers a double solution—reducing the growing volume of organic waste from coffee shops while creating an affordable alternative energy source. In Aceh, coffee is abundant, which means the raw material is readily available, especially for small and medium-sized businesses."

The patented method opens opportunities beyond household use. The briquettes could serve small industries and local energy needs while encouraging the adoption of a circular economy, where waste is transformed into products with real economic value instead of being discarded.

The achievement has also become a source of pride for Teuku Umar University.

Rector Prof. Dr. Nyak Amir described the patent as clear evidence that university research can provide practical solutions to real-world challenges.

"This patent demonstrates that academic research can address environmental issues while meeting society's growing demand for sustainable energy," he said. "We will continue supporting applied research that creates tangible benefits for communities and contributes to Indonesia's broader vision of impactful innovation."

What began as something as ordinary as leftover coffee grounds has become a symbol of how thoughtful research can turn everyday waste into a cleaner source of energy—and a reminder that sometimes, the next breakthrough is hidden in what most people throw away.