Business groups are warning the Abbott Government against any broadening of the carbon tax repeal Bills, fearing big and small companies could find themselves under investigation if they fail to pass on savings from axing the levy.
Peak business lobby the Australian Industry Group said the carbon tax would eventually go but cautioned that any further changes to the repeal legislation needed to be examined properly so as not to cause more pain to companies.
"Any further amendments intended to ensure that carbon savings are passed on should be carefully scrutinised," group chief executive Innes Willox said.
"Amendments that drag in the broader business community would be unworkable and cause regulatory mayhem, particularly as so many businesses have absorbed the carbon price and not passed it on to their customers."
Clive Palmer last night denied that his demanded changes to the carbon tax repeal Bills could hit companies other than power generators with penalties should they fail to pass on savings.
But business groups fear the Palmer changes are so broadly drafted it could catch other industries such as airlines, supermarkets and small businesses.
The Government says it has agreed to the Palmer United Party's amendments, but has refused to give a clear explanation as to who will be penalised under new laws.
The WA Chamber of Commerce and Industry said Perth businesses were looking for certainty and the longer the tax was in place the bigger the headache for companies.
"The carbon tax increases costs for business, impacts on our global competitiveness and the clear expectation of business after the Federal election was that it would be repealed," CCI chief Deidre Willmott said.
The Business Council of Australia said it was essential that changes to climate change legislation were negotiated in a transparent fashion so the effects on business were clear.
"Anything short of this will fail the national interest and adversely affect both business and the community," president Catherine Livingstone said.
Releasing its own analysis that claimed the carbon tax was now up to 20 per cent of the total electricity bill for some large businesses, Ms Livingstone said all "green energy policies" were punishing the corporate sector.
But green lobby group Climate Institute said the Senate had done the right thing by rejecting the repeal Bills.
Institute chief executive John Connor said it was clear new crossbench senators were struggling with the implications of repealing laws that were "working as intended".