OUR INDUSTRY

 AN EXAMPLE OF STEEL AND SUSTAINABILITY

After the 1931 Napier earthquake, a ship loaded with steel for the Sydney harbour bridge construction, was diverted to Napier to redirect its steel shipment to the rebuild of wool sheds to support the local post earthquake economy.

Those wool sheds were eventually deconstructed and eighty three years after that first deployment, those same steel beams were incorporated into the construction of new buildings in Napier.

If the embodied carbon in that steel had been fully factored into the original use buildings – as per today’s environmental impact measuring practices – then that same steel contributed less CO2 to the construction project than the contractors did in flipping the tops off the beer bottles for the roof shout!

This is what it looks like when you consider the life of a product in environmental assessments rather than just considering the life of the first, and often the only, building the product is embedded in.

There are many stories like this one and I wonder what buildings the woolshed steel will be redeployed into as another 80 years roll by.

HISTORY OF STEEL IN NEW ZEALAND

Steelmaking in New Zealand

New Zealand’s steel industry dates back to the 1800s, when European settlers first recognised the potential of the magnetic black iron sands found along the west coast of the North Island.

Over the next century, attempts to smelt iron from these sands faced challenges—traditional blast furnaces would clog due to the sand’s unique composition. By the early 20th century, attention shifted to limonite, a rich iron ore found in the Golden Bay area. This material could be smelted more easily, and in 1920, the Onekakā Iron and Steel Company was established. From 1924 to 1935, it led New Zealand’s iron smelting efforts, but economic and market conditions eventually made the operation unsustainable.

Despite setbacks, the potential of iron sand remained compelling. It wasn’t until the 1960s, with the development of direct reduction techniques and Electric Arc Furnaces (EAFs), that engineers successfully pioneered a process to unlock the value of New Zealand’s iron sand deposits—laying the foundation for a modern, sustainable steel industry.

New Zealand Steel is the only manufacturer of Steel in New Zealand which operates at Glenbrook in Auckland. The Glenbrook plant is the only steel making plant in the world that produces steel from iron sand. NZ Steel will shortly be commissioning its new state of the art EAF which will draw raw product from the metal recycling operators and reduce CO₂ emissions from the Glenbrook site by up to 1,000,000 tons per year.

The Rise of Electric Arc Furnaces

While traditional blast furnaces rely on carbon from coal to produce virgin steel. In contrast, EAFs use electrical induction to melt recycled steel, eliminating the need for additional carbon. The primary source of emissions in EAFs comes from the electricity used—meaning that when powered by renewable energy, such as the NZ Steel EAF at Glenbrook Auckland, emissions drop even further.

Today, about 30% of global steel production comes from EAFs, and research continues into technologies that could produce zero-carbon steel.

Why Steel Endures

Throughout history, steel has remained vital to human progress thanks to its:

• Strength
• Workability
• Durability
• Magnetic properties
• Weldability

From ancient tools to modern skyscrapers, steel continues to shape our world—and its future looks even more sustainable.

Steel and the Circular Economy

Steel is the only building material that can be recycled infinitely without losing quality. That’s why it’s often called the “rockstar” of the circular economy. In contrast, many materials labelled as recyclable are actually “downcyclable”— each time those products are ‘recycled’ the quality and useability is downgraded and eventually they end up in landfills.

Recycling steel offers a wide range of environmental, economic, and practical advantages that make it a cornerstone of sustainable development:

1. Energy Savings

Recycling steel uses significantly less energy than producing steel from raw iron ore. In fact, it can save up to 75% of the energy required for traditional steelmaking. This efficiency helps reduce greenhouse gas emissions and conserves valuable resources.

2. Reduced Carbon Emissions

Electric Arc Furnaces (EAFs), which are now commonly used in steel recycling, emit far less CO₂ than blast furnaces. When powered by renewable energy, EAFs can reduce carbon emissions to near zero—making recycled steel a key player in climate-conscious manufacturing.

3. Conservation of Natural Resources

Recycling steel reduces the need for mining iron ore and coal, preserving natural landscapes and ecosystems. It also minimizes the environmental impact of extraction and transportation.

4. Infinite Recyclability

Unlike many materials that degrade with each recycling cycle, steel can be recycled indefinitely without losing its strength or quality. This makes it ideal for a truly circular economy.

5. Economic Efficiency

Steel recycling supports a robust industry that creates jobs in collection, processing, and manufacturing. It also lowers production costs for manufacturers by reducing the need for raw materials and energy.

6. Waste Reduction

Recycling steel helps divert millions of tons of waste from landfills each year. This not only reduces environmental pollution but also extends the lifespan of landfill sites. Approximately 90% of steel from building demolition is reused or recycled.