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Zero carbon is within our grasp

Ten years ago, any conversation might have been about whether a zero carbon steel industry was even possible.

Now we have proved it is, with the launch of Hōtaka Whakakore Puhanga Waro marking a global first for the construction sector, which can now offer a zero carbon steel option for most steel products used in New Zealand.

The offsetting programme includes a robust set of programme rules to determine the underlying requirements for calculating the emissions for offsetting to ensure integrity of the programme.

Emissions are offset via Ekos, a leader in carbon management and environmental financing, through the calculator; the offsets are sourced from native forest projects.

These projects deliver multiple biological, ecological and social co-benefits beyond simply carbon sequestration. This programme can be expected to change the conversation around the carbon performance of steel, with the sector knowing that a reliable option for net zero carbon steel now exists.

In general the construction industry is having a lot of conversations around

carbon in steel, with MBIE having developed two emissions mitigation frameworks under the Building for Climate Change.

Hōtaka Whakakore Puhanga Waro, the zero carbon steel programme, is a game changer for steel, a known hard-to-abate product. It provides a carbon neutral steel option now, to build upon all of the circular economy benefits that steel offers through its reuse and recycling, noting that 85 percent of all steel waste from construction in New Zealand is recycled.

But the reduction of the steel industry's emission to meet the 2050 net zero carbon target is only part of the challenge.

Steel and iron produc-

tion is the single largest industrial source of CO2 emissions in New Zealand, representing 55 percent of industrial emissions and around five percent of total gross emissions. Carbon is primarily used in the steel-making process as a reductant, rather than an energy source.

There are many research projects looking at green steel options using alternative reductants, including work supported by New Zealand Steel, at Victoria University of Wellington, looking at hydrogen as an alternative reductant.

While that technology is not yet available, it is important for the industry to utilise carbon offsetting as a mechanism to reduce net emissions.

The novelty of the zero carbon programme is that it covers a number of different steel products. It includes painted steel used in roofing and cladding, rebar used in concrete, light-gauge steel framing, heavy structural steel and stainless steel.

We are not aware that a programme of this type, at this level of detail, exists anywhere else in the world at this time.

The main users of the programme will be either the building product suppliers or fabricators, who may decide to bring it into their front end to offer