The government says its $10 billion clean-energy fund, which the Coalition has vowed to scrap, will be volatile but "financially self-sufficient" over the long term.
The Clean Energy Finance Corporation, established to invest in clean-energy projects and technology, is expected to match the government's five-year bond rate, now 2.8 per cent, its investment mandate has revealed.
"By adopting a commercial approach, it is expected that the corporation will invest responsibly and manage risk so it is financially self-sufficient and achieves a benchmark rate of return," according to an explanatory memorandum issued on Wednesday.
Loans at cheaper rates would not exceed $300 million each year, it said.
The corporation has flagged plans to sign contracts with financiers and clean-energy projects, such as wind and solar energy, in coming months.
The corporation is able to deliver funds from July.
But the Coalition has vowed to scrap the CEFC if it wins the federal election and not honour any of its commitments.
It also says it will save $20 billion through scrapping Australia's carbon price and associated industry and household assistance.