The Green Party plans to replace the Emissions Trading Scheme with a Kiwi Climate Fund to drastically reduce emissions.

The party, led by James Shaw, has laid out its plan this afternoon to see New Zealand carbon-free by 2050.

"The current ETS is worse than useless," former leader and party stalwart Jeanette Fitzsimons said. "Even the government admits it hasn't reduced emissions, but some big polluters have made a lot of money out of it."

The party in government would put a simple, transparent charge on all climate pollution and use the revenue to fund tree planting around New Zealand.

Remaining surplus would be returned to every New Zealander over 18 each year as a dividend - estimated to be $250 in the pocket per person in 2020.

Farmers would no longer be exempt, as all agriculture emissions would be charged for.

Leader James Shaw revealed the plan to a crowd of more than 200 in central Auckland.