Power Supply showcases a more straight forward blues-influenced raw heavy metal sound that dispenses entirely with the experimental approach of the previous two albums, an approach that matched the zeitgeist of the time, reflecting the renewed and revitalised surge of interest in classic heavy metal brought about by the younger NWOBHM bands.

[3] New guitarist, John Thomas from the Southern rock outfit, The George Hatcher Band ventured away from the sometime progressive rock, psychedelic minor chord focused inclinations of the previous guitarist, Tony Bourge, to replace it with a more direct heavy metal blues rock Rhythm and blues sound that took the band in new directions with this and subsequent albums, which appealed to the older fans of the band as well as attracting new audiences.

[4] Dave Charles, who had previously worked with Dr. Feelgood (Down by the Jetty), Dave Edmunds and Brinsley Schwarz Hype, was the sound engineer on the album, recording the band at Rockfield Studios.

Science fiction fantasy artist and book-cover illustrator Adrian Chesterman provided the futuristic artwork for the sleeve design.

[5] All tracks are written by Burke Shelley and John Thomas, except where noted