Submitters on the Government's Carbon Zero Bill favour an all-gases target but many were split on what that should look like.

About 58 per cent of the roughly 3000 unique submitters - excluding templates from groups including Greenpeace, Generation Zero and Forest & Bird - backed a target that would potentially include all greenhouse gases, including methane and nitrous oxide.

About 22 per cent favoured a target that was net-zero by 2050 for long-lived gases - such as carbon dioxide - but aimed to stabilise shorter-lived gases such as methane.

But about 8 per cent of submitters suggested alternative options. And some firms, including Z Energy and Air New Zealand, backed an all-gases target but suggested a more granular approach within that.

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The fuel retailer said it recognised the complexity of including short-lived gases in the target straight away.

"We would suggest a cap on short-lived gases with a re-concerted effort on innovative solutions - such as biological methane inhibitors - that would not only address these highly destructive gases, but offer an innovative commercial opportunity for the New Zealand agricultural sector," the firm said in its submission.

Air New Zealand said the all-gases target was needed to ensure fairness and meaningful reductions. It cited modelling by the New Zealand Institute of Economic Research suggesting the cost to the economy was little different from a target that also aimed to stabilise short-lived gases by 2050.

"A target that includes all greenhouse gases still enables short and long-lived gases and specific sector challenges - including relative cost abatement and technology considerations - to be considered when emissions budgets are set."

The treatment of methane is critical for the effectiveness of the country's emissions trading scheme, given that agriculture accounts for about half our emissions. Heavy industry players - generally large carbon emitters - also want to ensure the burden is carried across the economy, but there are doubts on how effectively methane and nitrous oxide can be mitigated.

While the Ministry for the Environment's consultation process in June and July was exhaustive, the 36-page summary shows the limits of "tick-box" surveys when it comes to more complex issues. The ministry also convened public meetings, workshops and hui.

The results will be combined with advice the Government has already received from the Parliamentary Commissioner for the Environment and the Productivity Commission. There would be further talks with other political parties before the Bill was introduced next year, Climate Change Minister James Shaw said.

"The vast majority of respondents want New Zealand to do everything we can to reduce our greenhouse gas emissions as much as possible, and offset the remainder, to reach 'net-zero' emissions by 2050.

"At the same time, there was a strong representation from people and businesses who, while supporting the overall direction, expressed caution about the speed and scale of the transition and the pressure it will put their sectors under," he said.

"We have to ensure that those concerns are heard and included as we put together the final shape of the Zero Carbon Bill. We need to take everyone with us and leave no-one behind."

More than 15,000 submissions were received in total, including templates and three-question forms filled in online and at public meetings.

Among the other survey results, there was strong backing for an independent Climate Change Commission.

Most unique submitters - 67 per cent - also favoured a legislated target now. More than half of businesses and research institutes also preferred that over the flexibility of leaving the target to the yet-to-be appointed Climate Change Commission.

About 60 per cent also said emitters should not have the option of using recognised emission credits from overseas. That was further split, 60 per cent of the councils submitting wanting the international option. Businesses were more evenly split, and more than 30 per cent of research bodies also said there should be access to international credits.

Fonterra was among firms favouring access to international credits. It also backed a target that set a firm ceiling on carbon but aimed to stabilise methane emissions by 2050.

It said a net-zero target for all gases was likely to have "significant negative impacts" on the livestock sector and rural communities.

Trustpower, which operates 19 hydro schemes and buys the output from Tilt Renewables' New Zealand wind farms, supported the call for long-term climate goals.

But it said it was important the core elements of such a scheme had bipartisan support, that it was internationally linked, and that the Government recognised the potential risk of carbon leakage if emissions were effectively "exported" abroad to less efficient producers and countries.