based on the numbers already being used by the Gillard government, the chances are excellent that their eventual carbon price is going to be around $83 a tonne.
This is the "high end" number assigned to what is called the "Social Cost" of carbon. Cut free from all the socialistic verbiage what it comes down to is that at $83 a tonne the price of emissions is high enough to permanently alter human behaviour- stop people driving, starting businesses, buying shares, basically shut down the freedom of Western civilisation.
This high price also makes renewable energy viable as an alternative to efficient sources of energy such as coal, nuclear and oil. Below this high price renewables are not going to be viable unless agricultural based renewables such as burning weeds and waste in cogen plants is considered or unless the addiction to windmill boondoggles is replaced by algae farming and wave power.
But $83 / tonne is there in black and white, and it is a figure that the Gillard-Greens alliance will be forced to use. If they don't hike the price to that level, none of their schemes will work. Of course the net effect will almost certainly be the mass closure or relocation of business and the reduction of Australia to a true banana republic. Except that bananas won't be viable to cultivate either - carbon tax on fertiliser and diesel will see to that.
Social cost of carbon: