The Challenge

Treating wastewater is energy-intensive — and staggeringly expensive. In the United States, water and wastewater systems account for about 3% of the nation’s electricity use, rising to more than 5% when infrastructure and transport are included.

Much of that energy powers massive fans that pump air into treatment tanks so oxygen-breathing microbes can break down waste — an effective but costly process.

The Plan

Physicist Moh El-Naggar is pioneering research on electric bacteria, microbes such as Shewanella oneidensis that survive by moving electrons outside their cells to external surfaces, creating tiny electrical circuits.

In devices called microbial fuel cells, electrodes capture those electrons as the bacteria consume organic matter in wastewater. The electricity produced is modest, but the real advantage is that these microbes don’t require oxygen to function, making it possible to treat wastewater without today’s energy-hungry aeration systems.

The Impact

If widely deployed, electric-bacteria systems could dramatically reduce the energy required for wastewater treatment while lowering costs.

They could also shrink the sector’s environmental footprint by reducing reliance on fossil fuels.

Smaller microbial systems would also enable more affordable, localized wastewater treatment in regions lacking major infrastructure, expanding access to clean water while turning waste into a resource.