‘Living cement’ uses bacteria to store and release electricity

Safety, comfort and warmth are just some of the things that homes provide their inhabitants. But in future, according to researchers at Aarhus University in Denmark, houses could take on another role: storing and providing electricity in their walls.

The world’s most widely used building material could soon be turned into “living energy devices”, according to the team, which embedded electricity-generating bacteria into cement to create a ‘biohybrid supercapacitor’.

“We’ve combined structure with function,” said lead researcher Qi Luo. “The result is a new kind of material that can both bear loads and store energy – and which is capable of regaining its performance when supplied with nutrients.”

The team added Shewanella oneidensis, a bacterium known for its ability to transfer electrons to external surfaces via extracellular electron transfer, into cement. Once embedded in the cement matrix, the bacteria created a network of ‘charge carriers’ capable of storing and releasing electrical energy.

“The material already shows performance well beyond what traditional cement-based energy storage systems have achieved, suggesting promising potential for future development,” a research announcement said.

Because microbial activity gradually fades due to nutrient depletion or environmental stress, the researchers designed an integrated microfluidic network within the cement that can deliver a nutrient solution containing proteins, vitamins and salts to keep the bacteria alive or ‘reawaken’ the system. With this method, up to 80% of the original energy capacity can be recovered.

“In practical terms, this opens the door to recoverable energy materials that maintain their function over time, without the need to replace batteries or perform costly repairs,” the announcement said.

The researchers also stress-tested the material under challenging conditions, finding it retained its ability to store and discharge electricity in freezing and hot temperatures.

The team connected six cement blocks together in series, providing enough energy to power an LED light. While that might not sound like much, they claimed the new material could provide a sustainable alternative to lithium and cobalt batteries for renewable energy storage.

“This isn’t just a lab experiment,” Luo said. “We envision this technology being integrated into real buildings, in walls, foundations, or bridges, where it can support renewable energy sources like solar panels by providing local energy storage. Imagine a regular room built with bacteria-infused cement: even at a modest energy density of 5 Wh/kg, the walls alone could store about 10 kWh – enough to keep a standard enterprise server running for a whole day.”

The work was published in the scientific journal Cell Press.

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