In an annual conference called Net Zero Economy Forum: Accelerating The Transition that took place in Sofia, Bulgaria on October 18th 2022, global construction companies discussed what are green buildings, green materials and the decarbonization technologies used by the industry.
Decarbonizing every step of the construction process is essential if the world wants to reach a true net zero economy. Buildings carry an enormous carbon footprint as 40% of global CO2 emissions are generated from the way they are built and operated.
Around 30% of those emissions are attributed to the building phase and 70% to the way they are used and operated afterwards.
Additionally, 50% of extraction of raw materials in the world is done to serve the construction industry.
One of the companies that took part in the panel “Green Buildings, Materials, and Technology” is Aurubis – an international leader in metals production and one of the largest recycling companies for metals in the world. It processes complex metal concentrates, scrap, and metal-bearing recycling materials into metals.
Aurubis also focuses on copper – production and recycling and its copper cathodes (a basic copper product) are known to contain around 50% of recycled material.
Iron silicate is another material that is also an area of focus for Aurubis thanks to its attribute to the circular economy. It is a by-product of copper smelting and can be utilized in the production of cement clinker – one of the main ingredients of cement. Cement, on the other hand, takes part in the concrete mix.
The material is currently used in many places around the world, mainly developed countries, as an ingredient in several areas in construction.
According to Emanuela Manolova, Iron Silicate Business Development Manager of Aurubis Bulgaria, “iron silicate is a low emissions product because the emissions from its production are significantly less than emissions from new substitute materials that need to be mined and produced. Therefore, it fulfills the criteria of a product that fits into the circular economy… It is not sustainable in any way for such materials to be discarded for waste.”
Therefore, an efficient way of minimizing the environmental footprint of the construction industry is for the companies to replace the main ingredients of cement and concrete with ingredients that are by-products of smelting and mining or any by-products left behind from the construction processes at different stages. These by-products can be utilized into the concrete mix and eliminate the need of extracting new raw materials which is a heavy-emissions step of the construction process.
At the Net Zero Economy Forum: Accelerating The Transition, the CEO of Holcim Bulgaria Rossen Papazov commented on why the net zero transition cannot happen unless the construction industry doesn’t find a way to eliminate its carbon footprint.
He explained that even though concrete and steel comprise under 5% each of the price of an average-sized building, the two materials are responsible for 50% of all emissions incurred from the construction processes. As it turns out, the importance of concrete is so big that it is also the most used material after water globally.
“Finding solutions for decarbonization of construction materials is critical and failure to do so threatens all the rest net zero efforts,” said Mr Papazov.
Since concrete exists from centuries, finding alternatives to replace it is challenging which is why most companies are trying to lower the emissions related to each step of the concrete production and utilization process.
What Holcim does to decrease the carbon footprint of its materials like concrete is to release a low emissions product range on the market. Some of those products are EcoPlanet cement and EcoPact concrete that come with reduced carbon footprint and represent a step close towards sustainable building solutions.
According to Holcim, ECOPlanet is the world’s broadest range of green cement and aims to tackle the challenge of sustainability by reducing emissions from cement by at least 30%. EcoPact concrete offers up to 90% lower CO2 emissions compared to standard (CEM I) concrete and is sold at a range of low-carbon levels from 30%-100% of lower embedded CO2.
One way that the company has lowered the carbon footprint of its materials and is able to offer them on the market as low-emissions products is utilizing waste or by-products from other industries that replace the extraction of new raw materials needed for the production of concrete. Other methods involve greening the operations with renewable energy and alternative fuels for transportation.