@mls14 once you're on the electoral roll in Australia, you'll potentially be fined if you don't show up and vote in an election. But there's no penalties if you never enroll to vote in the first place...
One thing that's often missed in discussions of compulsory voting is that if the state requires everyone to vote then the state must also make it _possible_ and _easy_ for _everyone_ to vote. It's the ultimate in enfranchisement if you look at it from that perspective.
If you're on the electoral roll and you really can't find anyone you're prepared to vote for, for whatever reason, and you don't want to pay the fine, you can always submit a blank ballot.