Power prices could continue to rise if Australia's renewable energy target isn't replaced, the Clean Energy Council fears.
In a briefing paper released on Wednesday, the group says investment in new renewable energy projects plunged this year, after reaching a high in late-2018.
Quarterly investments in new renewable energy projects reached a high of over 4500MW in late 2018, but slowed to 800MW in each quarter this year.
The Clean Energy Council is now renewing its call for a national policy to give investors confidence.
The briefing paper comes about a week after Australia met its 2020 renewable energy target, which the federal government doesn't plan to extend.
Under the target, 33,000 gigawatt-hours - or 23.5 per cent - of Australia's electricity will come from renewable sources by 2020.
Clean Energy Council chief executive Kane Thornton fears future investments will drop off without a new target, which could lead to higher power prices and risk the reliability of electricity.
"Investors have been forced to balance their record enthusiasm for Australian wind and solar projects with a lack of national policy, growing threats of government interference in the energy market and a range of out-of-date regulations," he said.
"With Australia's coal-fired power stations ageing rapidly, it is essential new clean energy projects are built now to ensure lower power prices and improved reliability when these old clunkers retire from service."
Although the bill hasn't returned to parliament, the coalition still plans to revive its so-called "big stick" legislation, threatening to break up energy companies if they are found to be jacking up prices.
The industry flatly opposes the proposal, and the Clean Energy Council fears it will keep investors at bay.
Energy Minister Angus Taylor is also yet to reveal how the government's plan to underwrite new power projects would work, or how much taxpayer money would be put towards the scheme.
Australian Associated Press