Uber director Lindsay Maxsted, once thought to have been past the prime of his career, has resurrected himself as Australia's most powerful director as measured by the size of the company boards on which he sits.

Exclusive research undertaken for The Power Index by leading ASX number crunchers Optimice reveals Maxsted's three board spots at global miner BHP Billiton, toll roads operator Transurban and Westpac (as chairman) total a hulking $191 billion, nearly $77 billion clear of second place-getter and fellow BHP director Carolyn Hewson.