The Climate Change Commission expects it will be able to release the detailed models behind its draft emissions budget in June or July - after the public has a chance to provide feedback on this draft, and after the final version is presented to the Government in May.
Right-wing think tank, The NZ Initiative, and the Major Electricity Users’ industry group, are among the critics of the Commission for not releasing all its modelling when it released its draft report on January 31.
Their argument is they need to understand the inputs and assumptions underpinning the Commission’s recommendations to provide well-informed feedback.
This is especially so, as the Commission itself has said the changes proposed are more significant than the economic reforms of the 1980s.
However, Commission CEO Jo Hendy told interest.co.nz it was “not critical" for stakeholders submitting on the advice to access its “modelling code and formulas”. The Commission has already published much of the data and assumptions it used.
The Commission declined a request made under the Official Information Act for it to release all its detailed modelling, saying it was still working on making it “open-source”.
It said in its current form, the models include information that is “commercially sensitive, proprietary, and/or provided to the Commission in confidence”.
Hendy told interest.co.nz, “Part of preparing the open-source models for release will involve ensuring any commercially sensitive material cannot be identified. This process takes time.”
The Major Electricity Users’ Group, whose members include the likes of Fonterra, Lion, New Zealand Steel, Norske Skog Tasman and BusinessNZ, said this was unsatisfactory for such a major piece of work.
The report, for example, suggests cutting livestock numbers by 15% by 2030, phasing out importing light internal combustion engine vehicles by 2035, and eliminating the use of coal to generate energy by 2035.
The Commission puts the upfront cost of the recommended changes (without factoring in the benefits) at $34 billion over the next 14 years.
Much of this cost will of course fall on the Major Electricity Users’ Group’s members.
Yet its chairperson John Harbord told interest.co.nz, “Simply understanding the calculations - I don’t think there’s any self-interest in that. That’s just wanting to be informed…
“It’s very hard to form an opinion on a recommendation if you don’t know how they got there.”
If the modelling is robust enough for the Commission to use to make far-reaching recommendations, it should be robust enough for scrutiny, he said, noting the Commission had otherwise been very good to engage with.
Harbord hoped the Group would still be able to provide feedback to the Government between the modelling being released mid-year and the Government making its decision on whether to accept or reject the advice by the end of the year.
The Government has already signalled it will accept the Commission’s recommendations at a high-level. Under the Climate Change Response (Zero Carbon) Amendment Act it would need to publish an alternative plan to reach the emissions reduction targets in the legislation, should it decide to reject the advice.
Finance Minister Grant Robertson said his “expectation” was for the Commission to unveil more details around its modelling once the report is finalised.
He didn’t provide interest.co.nz with a clear answer when asked whether he had formally made that expectation clear to the Commission.
“I know there’s a lot of people interested in interrogating the model - not just inside government, but outside as well,” Robertson said.
“But ultimately, they are questions for the independent Climate Commission.”
Hendy said when the Commission contracted the development of the C-PLAN, DIM-E and ENZ models, “we specified a requirement for them to be open-source with supporting documentation on how the models work”.
“We are confident that our economic and technical models are robust and fit for purpose,” she said.
“They have been developed by modelling experts, have been independently reviewed by internationally renowned experts, and our C-PLAN model described as “best in class”. Our results line up with international studies.
“We have released a broad range of information as part of our consultation, including the modelling assumptions, inputs and outputs, so people can make submissions on the draft advice.
“We are prepared to reconsider our assumptions based on evidence provided through the consultation process, and we will be re-running models and doing additional sensitivity analysis based on what we have heard from consultation.”