Researchers have harnessed deep-sea hydrothermal vents to produce electricity.

Masahiro Yamamoto of the Japan Agency for Marine-Earth Science and Technology in Yokosuka and Ryuhei Nakamura of the RIKEN Center for Sustainable Resource Science in Wako and their team exploited the differences in chemistry between sea water and fluids that leak from hydrothermal vents. Steep concentration gradients of chemicals such as hydrogen sulphide allowed the researchers to generate more than 21 milliwatts of power from a fuel cell based on a platinum cathode and an iridium anode.

This successfully powered three light-emitting diodes 1,000 metres below the surface, both at an artificial vent created by deep-sea drilling and a natural vent.

Angew. Chem. http://doi.org/f2dtrm (2013)