The new rules for sustainable stainless steel selection
08 June 2021
Sustainability has become a determining factor for buyers of stainless steel. However, variations in production, recording and reporting of data can make it challenging to compare different suppliers on the same basis. Camilla Kaplin, Senior Manager, Environment for Outokumpu, offers some guidance.
In today’s climate-conscious market, the environmental and sustainability performance of any company is only as good as its supply chain. In addition, data on carbon footprint is essential for original equipment manufacturers (OEMs) to calculate their own carbon footprint.
The people responsible for specifying and purchasing materials like stainless steel need to know the right questions to ask when choosing a supplier of stainless steel.
Do they publish environmental performance data according to the ISO 14040 standard?
The most reliable sources for data on carbon footprint are Environmental Product Declarations (EPDs). By insisting that these follow the ISO 14040 standard, a buyer can assess a product’s entire life cycle across three scopes:
• Scope 1 covers direct emissions from a supplier’s operations which, for stainless steel, could include burning fuel to heat furnaces.
• Scope 2 accounts for indirect emissions, such as electricity generation for powering equipment such as electric arc furnaces.
• Scope 3 emissions are generated during production of raw material. They cover the energy used in mining, ore processing and scrap recycling. These are often the largest source of emissions for materials such as stainless steel.
The combined figure of all three scopes is the most important as individual scopes can vary widely between suppliers. The other benefit of following the standard is that EPDs need to be verified by an independent third party such as the Institut Bauen und Umwelt (IBU). This ensures the data is reliable and can be compared between suppliers on equal terms.
How much production is based on recycled content?
As an additional measure, the level of recycled content in stainless steel products can be used as a guide to how their carbon footprints compare.
That’s because recycling stainless steel consumes less energy (and creates fewer emissions) than processing virgin ore. According to Germany’s Fraunhofer Institute, each tonne of austenitic scrap used in making stainless steel saves 4.3 tonnes of CO2 emissions.
Recycled content varies widely, depending on the steel mill’s procurement strategy. Yale University has found the global average of recycled content in stainless steel to be 44 percent.
Outokumpu base its production on almost 90 percent recycled material, the highest level in the industry. That shows up in the carbon footprint in its EPDs, which show that its CO2 emissions are around five times lower than some other stainless steel producers.
What is their local environmental impact?
The local environmental performance of suppliers at their own plants is another important performance measure. The steel production process generates dust and wastewater that, if not treated, could impact nearby communities and wildlife by affecting air, watercourses and land.
So, if you are using sustainability as a selling point, it’s important to ask for data on how your stainless steel supplier treats process water, captures and recycles dust, etc. This protects the environment and enables recovery and reuse of valuable raw materials.
Look for long term performance
While initial purchase cost is important, it’s only a small part of the picture when it comes to specifying materials. Many of today’s operators now use life cycle costing instead. This covers initial cost, as well as the direct and indirect costs that mount up during operation, maintenance, and end-of-life disposal.
The right grade of stainless steel can extend an installation’s useful life by decades. One example is the Tokyo Waterboard, which adopted stainless steel pipes for its water network. These are designed to last 100 years instead of the 20-year lifespan of some other modern materials. They have drastically reduced water leakage, as well as disruptive road works – a valuable but intangible benefit in one of the world’s most densely populated cities.
It can make a lot of financial sense to ask for an expert opinion before specifying a material that is already familiar.
Find out what third parties are saying
The final area of focus to help you compare sustainability performance is by taking a look at industry bodies, sustainability indexes and ratings. Signing up for international programs and initiatives will show how seriously a supplier takes sustainability.
Examples include the UN Global Compact and Sustainable Development Goals. Other programmes specially developed for the steel industry are the ResponsibleSteel initiative and Worldsteel’s sustainability development charter.
Choosing a supplier that has made these commitments will only strengthen your own commitment to environmental sustainability.
It is also worth looking ahead at the plans and goals your suppliers have set for the future. For example, like many industrial operators, we have signed up for long-term climate targets in line with the Science Based Targets initiative. This independent body has the goal of helping to set realistic goals to limit global temperatures rise to well below 2°C compared to pre-industrial levels.