However , in contrast with the constitutions of other Commonwealth Realms such as Canada which formally grant extensive reserve powers to the Monarch , even the formal powers of the Queen of Australia are extremely limited , and most powers can only be used by the Governor-General . However , in contrast with the constitutions of other Commonwealth Realms such as Canada which formally grant extensive reserve powers to the Monarch , even the formal powers of the Queen of Australia are extremely limited , and most powers are only exercisable by the Governor-General .