While Australia is making some progress towards decarbonisation, it can make a huge impact in the construction industry – which, globally, is responsible for 40% of the world’s annual greenhouse gas emissions. The biggest contributor to the industry’s carbon footprint is concrete – the second most consumed material in the world after water, used so copiously that its emissions are greater than all countries except for China and the USA. Concrete contributes 8% of the world’s carbon emissions.
A new report by Hatch, an award-winning multidisciplinary leader in engineering, operational and development projects in the metals, energy, and infrastructure industries, has found that ‘green concrete’ has the eco credentials to be a key driver in reducing Australia’s emissions.
The author of the report, Dr Ezgi Kaya, is a structural engineer at Hatch Australasia, where she co-leads initiatives on low-carbon concrete and parametric design. She has almost a decade of research and engineering consultancy experience across multiple sectors, and a broad knowledge in advanced design and analysis of complex structures under static and dynamic loadings such as earthquakes, impacts and blasts.
Kaya says green concrete is a sustainable and environmentally friendly alternative to traditional concrete, and an excellent solution for reducing carbon emissions in the construction industry.
“Unlike conventional concrete, which requires a considerable amount of energy and resources to produce, green concrete often uses recycled materials and minimises the use of Portland cement, a major contributor to carbon emissions.
“To date, green concrete has been used in more than 60 projects across different sectors in Australia, including infrastructure, buildings, industrial, marine and geotechnical. Given that the carbon reduction achieved through its use can be as much as 80%, the potential for green concrete to positively impact our emissions targets is monumental.
Kaya says Australia is a country that has a vast potential for green concrete usage, thanks to its abundance of resources such as recycled aggregates, fly ash and slag. These materials can be used as a replacement for traditional aggregates and cement, making the production of green concrete more sustainable and eco-friendly.
She says: “Replacing just 50% of traditional concrete with green concrete could reduce Australia’s carbon emissions by approximately 17 million tonnes annually, which is equivalent to removing four million cars from the road.”
Green concrete offers numerous benefits beyond emissions reduction – it is more durable, more fire resistant, and has higher engineering properties including high early age strength, less shrinkage. Its use in construction can lead to more sustainable and resilient infrastructure that is better equipped to withstand the impacts of climate change.
Designed to be more sustainable and environmentally friendly than traditional concrete, the key benefits of green concrete include:
• Reduced carbon footprint. One of the most significant benefits of green concrete is that it has a lower carbon footprint than traditional concrete. This is because it typically contains recycled materials such as fly ash, slag, and silica fume, which reduces the amount of cement required to make the concrete. Cement production is a significant source of greenhouse gas emissions, so reducing the amount of cement needed is one of the most important steps towards reducing the carbon footprint of concrete.
• Improved durability. Green concrete often lasts longer than traditional concrete, due to its better resistance to cracking and shrinkage. This is because it typically contains additives that improve the concrete’s strength and reduce the amount of water needed for mixing, which delivers a more durable finished product.
• Energy efficiency. Green concrete may improve energy efficiency. It is designed to have better insulation properties, thus lowering the amount of energy needed to heat and cool buildings made from the material.
• Cost savings. While green concrete is slightly more expensive to produce than traditional concrete, it offers cost savings in the long term. This is because it typically requires less maintenance and repair over its lifetime, which means lower ongoing costs for building owners and operators.
• Reduced waste. Green concrete helps reduce waste by using recycled materials that might otherwise end up in landfills. This helps conserve natural resources and reduces the environmental impact of construction projects.
The use of green concrete is already gaining traction around the world. It has been used in the construction of high-profile buildings such as the Louvre Abu Dhabi and Amsterdam’s Schiphol Airport.
In Australia, the benefits of green concrete are being recognised by industry leaders, who are advocating for its widespread adoption. Hatch’s engineers are working with clients to identify projects in which green concrete can be used. The goal is to make this the new normal within the next few years.
“As Australia continues to push towards a sustainable future, the adoption of green concrete is a crucial step in achieving its decarbonisation goals. By embracing this innovative and environmentally friendly construction material, Australia can not only reduce its carbon footprint but also create a more sustainable and resilient built environment,” Kaya says.