NZ companies have been quietly abandoning their climate targets without mentioning that fact to the public, says an expert in sustainable business.

Air NZ made headlines last year when it announced it would not meet its much publicised 2030 target.

The airline had set its target under the Science Based Targets Initiative (SBTI), a global non-profit that independently verifies company targets as being in line with collective efforts to keep the planet under 1.5 degrees heating.

But Associate Professor Pii-Tuulia Nikula of the Eastern Institute of Technology said several New Zealand companies had dropped out quietly without any announcement, after publicising joining the scheme.

"There are currently business in the SBTI database from New Zealand that have expired commitments, so basically they have made a commitment but then failed to actually set a target within the deadline. At least one of them is still promoting their target without mentioning that it has actually expired," she said.

Other companies had set and even met their initial targets, when the scheme was easier to join, but quietly exited after finding progress too tough, she said.

Despite facing criticisms of being too lenient, SBTI is widely seen as the gold standard for certification, because of its global reach and independence.

The net-zero validator started removing companies who did not meet its requirements in 2023. Its new standard requires companies to tackle supply chains emissions as well as direct emissions.

Some companies dropped out after realising they had not thought through whether they could actually set and meet an ambitious target, said Nikula.

RNZ approached three companies who have been removed or withdrawn from the scheme.

None wanted to be interviewed, but they each sent emailed statements in reply.

Kiwi Property Group said the reason SBTI's database listed it as "commitment removed" was that it had considered setting targets, but never did.

A spokesperson said she could not find any information recorded as to why the company did not follow through.

Silver Fern Farms is also listed on the database as 'commitment removed'.

Its spokesperson said it was still committed to being in the group, but was waiting for the sheep and beef-farming part of its targets to be approved by SBTI.

The company's website says it will set a supply chain target in 2023 however its sheep and beef targets were only submitted last year.

A spokesperson said approval could take months because of the complexity of the standards for agricultural emissions. Silver Fern's targets for farmer-suppliers are cutting per-kilo emissions from beef by 24 percent by 2033 below 2023 levels, and reducing total emissions from sheep by 10 percent over the same period.

Auckland Airport has pulled out, after being the first airport in the world to set a target under the initiative.

It met its first target under SBTI ahead of schedule in 2020, but pulled out of further participation when the criteria were changed to cover supply chain emissions, it said.

For the airport, this covers the jet fuel burned by Air NZ and other airlines.

"Right now, more than 90 percent of Auckland Airport's emissions inventory is from aircraft emissions and with the lack of a clear decarbonisation pathway for the aviation industry we did not seek SBTI verification over our updated carbon reduction target," it said.

"That doesn't mean we aren't continuing to do our bit towards decarbonising aviation."

Nikula said the targets were a double-edged sword - if they were too tough, companies fail, if they were too easy they do not achieve the change the planet needs.

"If businesses are getting a little bit scared of potential backlash if they're not able to reach their targets it might mean more business withdraw, but we need to have some transparency and accountability as well, so you can't just make a light commitment and not do your best to reach those targets."

SBTI has weathered its share of criticism for being too lenient by allowing carbon offsets instead of only real emissions reductions.

And last week one of its main funders - billionaire Jeff Bezos - ended his funding amid a US pullback from climate action under President Donald Trump.

Nikula said while the scheme might be imperfect, it was still probably the best widely available option for companies globally - and many companies were still opting for that independent seal.

One of those is mobile company 2 Degrees, which will be putting its cellphone towers into microsleeps to save power and taking other steps to reduce its carbon emissions under its new SBTI target.

Combined with electrifying its car fleet and making use of more renewable power, it hoped to slash emissions 90 percent by 2030.

2 Degrees chief executive Mark Callander said his company was one of first telecommunications businesses to have its net zero targets verified by SBTI.

"If you think about it a large portion of our direct control will come through our energy consumption."

"There is technology which allows us to put out towers into what is known as a micro sleep, which reduces energy consumption."

He said the short sleeps kicked in at times of low use and the towers restarted instantly when they were needed so mobile services were unaffected.

By 2040, the mobile network wanted to have slashed emissions from its supply chain too, by building sustainability into its deals with suppliers.

Callander was confident his company can meet its goals, and said shareholders and employees were very supportive.

Eloise Gibson/RNZ