The Greens would be open to forming a coalition with the Labor party to get over the line at the federal election, MP Adam Bandt has said.

On ABC's Q&A on Monday night, the Greens MP, who was formerly the party's deputy leader, said the parties' previous co-operation in 2010 was "one of the most productive periods" in Australian politics.

"You look at Germany, they're on the way to generating 30 per cent of electricity from renewables, that's because back in the '90s they had Labor and the Greens co-operating together. That's what I would like to see happen," Mr Bandt said.