Australia’s only nuclear reactor – the Opal multi-purpose research reactor at the Australian Nuclear Science and Technology Organisation’s (Ansto) Sydney campus – has returned to power following an extensive months-long planned shutdown period to undergo essential maintenance and upgrades.

The first-of-a-kind project for Ansto was the most significant engineering maintenance and upgrade programme in Opal’s 17-year history.

Central to the upgrades was the replacement of Opal’s cold neutron source. This device slows down neutrons as they travel from the Opal reactor through to the large scientific neutron beam instruments at Ansto’s Australian Centre for Neutron Scattering, increasing the performance for researchers looking at the structure of materials in atomic detail.