How would a 25% gas export tax work?

As the name suggests, a gas export tax is only applied to gas exported overseas.
Any Australian gas exported overseas would attract a 25% gas export tax.
Gas companies could avoid the export tax by selling the gas to the Australian domestic market, increasing domestic supply and lowering domestic gas and electricity prices.
A gas export tax would not affect the price of Australian gas exports for Australia’s trade partners because commodities like gas, oil and coal are not like manufactured products. Gas is sold into a world market at the world price. No one in the world pays a ‘premium’ for Norwegian gas because the Norwegians impose a 78% tax and Australian gas does not currently sell at a discount on world markets because we have been giving our gas away for free.
The gas export tax will be absorbed by the gas companies such as through lower profits and dividends for their owners.
A gas export tax would not stop gas export companies from meeting their existing contractual obligations. Australian gas exports already far exceed the volume of ‘contracted’ gas supplies. In fact, last year Australia sold more ‘uncontracted’ or ‘spare’ gas on what is called the ‘spot market’ than all of the gas used in Australia by all households, all industries and all electricity generators.