"Within our lifetimes, a smart, green economy will be the only economy still working."
He contrasted the Government's "risky" investments in fossil fuels and intensive farming with Greens' proposals - investment in clean technology and energy.
Dr Norman admitted that, if elected, the party would have to "pick winners" to achieve a green economy. A Green government would develop clean energy as an export industry by forming partnerships with power companies. It would also export expertise in geothermal and possibly marine energy.
Asked whether there was a risk in backing developing technologies, he said clean energy was a safe bet because there was huge growth in that area.
The party would encourage clean technology by providing around $330 million a year in research and development tax credits which would favour sustainable projects.
The party was reviewing its policy and expected to re-cost these measures before the 2014 general election.
Dr Norman said its spending programme would be partly financed by redirecting the billions spent on roads and tax cuts for the wealthy.
The Green vision involved several forms of taxation - a capital gains tax, a price for carbon and an earthquake levy.
The introduction of these measures would be "courageous", as opposed to National's tax cuts - $14 billion in four years - which had favoured high-income earners.
Dr Norman argued that an earthquake levy was a popular measure, and would have raised $1 billion by now. A 3 per cent levy on incomes above $70,000 and a corporate tax rate of 30 per cent would have raised a fifth of the $5.5 billion rebuilding cost.
The Green Party confirmed it would allow some new mining ventures and that it did not oppose oil drilling in shallow waters.
Dr Norman said mining was an "inescapable part" of the New Zealand economy. Greens would ban new coalmines but allow mining which had a low cost to the environment.
Labour Party environment spokesman Grant Robertson said he believed it did not signal a change in mining policy for the Greens, but the fact that the party would allow some mining "had not been highlighted before".
He said Labour's policy did not go as far as banning coalmines, but these differences could be discussed if a Labour-Greens coalition was on the cards in 2014.
NATIONAL BELOW 50 PER CENT IN POLL
The National Party has lost popularity in the wake of the Budget, with Labour and the Greens both making gains.
A TVNZ-Colmar Brunton poll showed National dropping four points to 47 per cent, the first time it has fallen below 50 per cent in two years.
Labour gained four points in thepoll, rising to 33 per cent, and the Greens jumped two points to 13 per cent.
The Act, Conservative, Maori and Mana parties all remained steady on 1 per cent.
The new figures showed National would have 58 seats in Parliament, or 61 when its coalition partners were included - enough to claim a majority.
Labour, the Greens and Mana fell one short of a majority with 59 seats.
The poll of 1005 voters, taken in the week after the Budget, had a margin of error of 3.1 per cent.