Energy security

UK generates usable electricity from americium

The UK's National Nuclear Laboratory (NNL) and University of Leicester have generated usable electricity from the chemical element americium in what it believes to be a global first. The achievement is seen as a step towards potential use of americium in so-called space batteries, which may mean future space missions can be powered for up to 400 years.

Americium is an element not found in nature, but which is produced by the radioactive decay of plutonium - which itself is produced during the operation of nuclear reactors. A team led by NNL has extracted americium from some of the UK's plutonium stocks, and used the heat generated from this highly radioactive material to generate electric current, which in turn lit up a small light bulb - all within a specially shielded area of NNL's Central Laboratory in Cumbria, England.

Space batteries are power sources for space probes which would use the heat from americium pellets to power sensors and transmitters as the probes head into deep space where other power sources such as solar panels will no longer function, NNL said. In this way, such probes can carry on sending back vital images and data to Earth for many decades - far longer than would otherwise be possible.

The breakthrough means potential use of americium in radioisotope power systems for missions which would use the heat from americium pellets to power spacecraft heading into deep space or to challenging environments on planet surfaces where other power sources, such as solar panels, no longer function. In this way, NNL said, such space missions can carry on sending back vital images and data to Earth for many decades, far longer than would otherwise be possible.