BIG business is demanding that a Coalition government redesign elements of the renewable energy target.

The Climate Change Authority yesterday confirmed renewables would represent 26 per cent of energy demand by 2020, overshooting the original target of 20 per cent because of falling demand for electricity and a surge in installations of rooftop solar panels, The Australian reports.

In its final report after a year-long review the authority rejected demands by companies including mining giant Rio Tinto to change the target for large-scale clean energy projects, concluding this would undermine investor confidence and exacerbate uncertainty surrounding climate change policy.

Business Council of Australia chief executive Jennifer Westacott signalled a renewed push for changes to the RET policy, so that it delivered a floating 20 per cent contribution to energy supplies by 2020 rather than being based on a fixed target of 41,000 gigawatt hours that represented a greater share of supply.

"At a time when households and businesses are under serious cost pressures, we should not be pursuing policies which add unnecessarily to electricity costs."

While industry sources said they were talking to both sides of politics to push for more radical reform of the RET, which has had bipartisan support, one senior executive said "the fight is about what the Coalition is going to do".

Climate Change Minister Greg Combet said the RET played an "essential role" and was an "important complement to the carbon price in delivering a clean energy future and making the most of Australia's significant renewable energy resources".

He said the government would respond to the authority's recommendations early next year.

The office of opposition climate change spokesman Greg Hunt declined to comment on the BCA calls for restoration of the original 20 per cent target.

"We will consider the RET review over the coming weeks and will consult on its recommendations," Mr Hunt said.

Tony Abbott has been under pressure to reverse his support for the RET, with Nationals senator Ron Boswell calling for its abolition. Labor chief whip Joel Fitzgibbon has said the target should be cut to a true 20 per cent.

Full report, The Australian.