any experience?

O&G, HV- if you have technical skills in that; possible to path yourself in but paper wise position is pretty hard, cos they need peeps that know how right now; old days of paper can get in is not anymore

Petronas involvement is power generation might just be in Gas field site or power generation.. other than that; unless you have the guts to go offshore- which require your technical to work on.

Shell; now more focus on the upstream offshore work; not very sure if they going to expand n have the DS E&P type yet.

You might want to try power generation company - since you are in aus; why not work there? 

Company in Aus power generation seems like they need alot; compare malaysia; which actually have it; but plan to develop further.

Advice: try to get instrumentation stuffs in you really want to go into O&G; really helpful ... um; ask empire23 abt why instrumentation; one of the forumer in /k/' he`s also same field as you but not power generation.