The Greens have released a policy to introduce a $5 billion loan guarantee scheme that would complement their target of a zero carbon economy.

They released the policy at the launch of their Tasmanian federal election campaign in Hobart.

Businesses willing to develop large-scale renewable energy projects would be eligible to apply for 100 per cent loan guarantees, similar to a scheme in the United States.

Greens Senator Christine Milne says the scheme would create jobs and give banks the confidence to lend money to renewable ventures in the future.

"Of course it is some risk for government to take on with loan guarantees but the benefits are so much greater because it means we will see the rollout of renewables as quickly as possible across Australia," she said.

"People trying to seek finance for large-scale renewable energy investments are having difficulties, and this is for solar thermal with storage, for geothermal, for wave power.

"In the United States, having recognised that, they moved to loan guarantees and that has been the basis on which they have managed to get the investment and the shift to renewables."