New Zealand's first Emissions Reduction Plan to drive the economy in a cleaner direction has been unveiled.

The scheme comes with nearly $3 billion for climate initiatives over four years - most of the money is going towards agriculture and transport.

While there are no moves to extend half-price public transport, $500 million will go towards helping low and middle income families make the switch to cleaner cars.

Professor Sally Brooker from the University of Otago, who co-leads the German-New Zealand Green Hydrogen networking alliance, spoke to Māni Dunlop.