 In 1955 , Oliphant initiated the design and construction of a 500 megajoule homopolar generator ( HPG ) , the world 's largest . This massive machine contained three discs 3 @.@ 5 metres ( 11 ft ) in diameter and weighing 38 tonnes ( 37 long tons ) . He obtained £ 40 @,@ 000 ( equivalent to A $ 1 @,@ 000 @,@ 000 in 2010 ) initial funding from the Australian Atomic Energy Commission . Completed in 1963 , the HPG was intended to be the power source for a synchrotron , but this was not built . Instead , it was used to power the LT @-@ 4 Tokamak and a large @-@ scale railgun that was used as a scientific instrument for experiments with plasma physics . It was decommissioned in 1985 . 
