Mud Battery Stops Marine Rust

Electricity from microbes could shield ships and rigs.

Ships, buoys, oil rigs and other ocean-bound steel objects can be protected from rust by plugging them into the seabed, says a team of Argentinian researchers.

The scientists have turned marine mud into a battery that can suppress corrosion by charging up stainless steel. The energy is free, clean and everlasting.

Stainless steel, which contains chromium, is much more resistant to corrosion than is ordinary steel. But in seawater it quickly acquires a layer of microbes and algae. These microbes' electrochemical reactions slowly erode the metal.