Examining Plastic Alternatives
Shouldn’t We Make Everything out of Stainless Steel? Uh… No! Part 2, Challenging the All-Stainless Vision
Jun
In the interest of giving readers the value of understanding both sides of this discussion without having to search out the opposing point of view elsewhere, I want to start this installment by giving the best version I can of the “steel man” argument for stainless steel, pun not intended:
If you use the most efficient process, you can made stainless steel at a relatively low carbon footprint (based on the energy used), something around 0.4 tons of carbon per ton of steel produced. This process uses scrap steel as its primary input. You put in 105% stainless and get out pure stainless. If we carefully recycled 99% of the stainless in the world, we would not need to do much more mining, but could just put this amazing metal into a virtuous loop where it is used until end of life and then up-cycled into something that might be even more precise and valuable than the stock it came from. Estimates of plastic carbon footprint range from 1.7 to 3 tons of carbon per ton of virgin plastic. We would be able to produce this metal for a fraction of that carbon footprint with no further extraction.
Before we unpack all this, let’s make it clear that you’ll get no argument from the Buoy team that stainless steel should be recycled. If the Buoy team thinks that plastic is a resource to be carefully recycled and reused, you can be sure that we think the same of stainless steel, aluminum and glass.
The good news is that a process does exist that could recycle all steel. It’s called the Electric Arc Furnace. You put in steel and you get out steel, with minor losses. Problem is that almost all the EAF processing is done in Europe and almost all the containers people are sourcing for reusables are Alibaba purchases made in China. China does not use EAF but rather blast furnaces to make steel, which can only take around 20% scrap. While steel produced from the EAF method does have a relatively low carbon footprint, around 0.4 tons of carbon per ton of steel, blast furnace steel has a footprint around 3 tons of carbon per ton of steel. The McKinsey study uses an industry average of 1.85 tons of carbon per ton of steel. The number for virgin plastic is generally between 1.7 tons to 3 tons, with the higher number being associated with it being burned at the end of its life. (My references for this information are here and here, if you want to take a deep dive. If in this case, or ever in these articles, you think I’m misinterpreting something, comment or message me and I’ll amend the article transparently if I agree with the correction.)
So to pay off the stainless steel vision, we either need China to scrap all their blast furnaces and replace them with EAF capacity or we need to start sourcing all of our stainless steel containers from Europe. Once the stainless container reaches its end of life, we would have to send it back to China or Europe to make more containers for us and the vision is complete. And here’s where your problems start…
The idea of China, or any industrial country, abandoning productive factories and reinvesting in new ones even for reasons of greater profit, much less for reasons of carbon reduction, is something of a fantasy. The transformation would cost billions. Who would pay for that? (Spoiler alert: no one.) Britain, which more or less invented industrialism, didn’t update their equipment, even though British engineers were inventing many of the updates, so was overtaken by later industrializers, like the US. After WWII, the US helped Japan build up its industrial capacity, without simultaneously updating its own. The result was Japan surpassed the US in industrial excellence. The point of those examples, is that even with clear incentives, established industrial environments are very slow to update to the latest technology.
The idea of getting containers from Europe is something of a non-starter due to cost. We might get high value steel from Europe, say for construction, automotive or medical devices, but the idea of getting a race-to-the-bottom commodity like a stainless steel food container is economically unfeasible.
Even if China did change and we got the low-carbon steel capacity we needed, we would not have enough scrap steel in existence to substitute out all the plastic containers to steel using our new EAF manufacturing capacity. To quote a World Stainless Organization report:
There is currently insufficient available end-of-life stainless steel scrap in all regions of the world to permit only scrap-based production to exist. This situation is likely to remain true for several decades to come.
In those intervening decades, people trying to buy low-carbon containers are competing with industries like construction and automotive, who are under hyperbaric pressure to reduce their carbon impact and are, therefore, willing and able to pay a premium price to do so. The folks buying stainless steel containers for circular economies are not going to be able to afford the low carbon stuff for many many years if ever. To see when that may happen, you can look at this article, which exhaustively projects how stainless steel production will play out through the year 2250 in a series of graphs and flowcharts of near-comedic complexity. (If you are a fan of the graphical presentation of information, give yourself a joyride and follow the link.) My interpretation of the graphs in figures 17 and 18 is that around 2050, we’d reach a steady state where about half the steel production is new and half is from recycled stainless. Realistically, the cheap end of the stainless steel market would not be getting the desirable recycled stuff, but at the very best, it would only be 50% recycled content, falling far short of the Stainless-Steel Optimist’s vision.
Let me cut this at a different angle, because I hear someone saying, “Hang on, I heard that 95% of stainless steel is recycled, so we can get containers that are 95% recycled stainless steel.” Yes, the industry claimsthat 95% of end-of-life stainless steel is recycled right now, which I will accept uncritically for the sake of this steel-man argument. But this 95% end-of-life statistic does not mean that the industry is producing stainless made of 95% recycled steel. Why? Because demand is going up at the same time. If we are recycling 1 ton of stainless steel every year, but the demand is 2 tons, the steel being sold cannot be more than 50% recycled on average. And we only get to that steady state point in 2050.
This got long and I’m sorry about that, but this stuff is legitimately complicated. The takeaway from this is that the steel-man version of a low-carbon forever loop of 95% to 99% recycled stainless steel would compete in carbon impact with plastic. The problem is that there is simply not a reasonable version of the world where you will be able to scale a supply of stainless steel containers made from 95% recycled content.
Thanks for reading. References below. Would love to hear your thoughts.
References:
McKinsey and Company, Climate Impact of Plastic
https://www.mckinsey.com/industries/chemicals/our-insights/climate-impact-of-plastics#/
Assessing the Long-Term Global Sustainability of the Production and Supply for Stainless Steel
https://link.springer.com/article/10.1007/s41247-019-0056-9
Stainless Steels and CO2: Industry Emissions and Related Data
What is the carbon footprint of steel?
https://www.sustainable-ships.org/stories/2022/carbon-footprint-steel
The Carbon Footprint of Steel
https://www.newsteelconstruction.com/wp/the-carbon-footprint-of-steel/
Electric Arc Furnace vs. Blast Furnace
https://www.steelsupplylp.com/blog/electric-arc-furnace-vs-blast-furnace