Let's assume that at some point in the near future our society makes the smart choice of turning toward degrowth. Yay!
That still would mean, however, that a certain level of heavy industry will be required. We can't feed and house and clothe and provide health care for eight billion people without producing at least some steel and some plastics. That's just reality.
So, what are the best alternatives for rapidly reducing carbon emissions while also managing to keep everyone alive?
@breadandcircuses Stop using heavy fuel oil for cargo ships (the largest source of emissions - every single individual ship has the annual emissions of 50 million cars or more).
Build more freight rail links where possible, and use nuclear+wind where a ship is required (we don't have the tech to get a train across the pacific yet).
Also, ban cruise ships, which are polluting enough that they make cargo ships look clean.
The article's conclusion - sounds like degrowth to me.
"The low-tech solutions
The picture painted above seems to offer little hope for carbon-neutral steelmaking and power production. However, there is a low-tech solution that could achieve it. We could adjust steel production to the available scrap supply both in quantity and quality. That would allow us to produce all steel from scrap in electric arc furnaces, dramatically reducing energy consumption and eliminating almost all carbon emissions. Of course, the intent should not be to replace steel with plastic composites and aluminum because they are even more energy-intensive to produce. The only solution is to reduce material use overall.
We could adjust steel production to the available scrap supply both in quantity and quality.
Reducing the steel output and using more common steel grades would not bring us back to the Bronze Age. As noted, global end-of-life ferrous scrap availability was approximately 450 Mt in 2021, which would allow us to produce roughly one-quarter of the current steel output. Furthermore, the scrap supply will continue to rise for the next 40 years, enabling us to produce more and more low-emission steel each year. By 2050, scrap availability is expected to rise to about 900 Mt, almost half of today’s global steel production.48 All that extra steel could be invested in expanding the low-carbon power grid without raising emissions first.
There is a lot of room to reduce the steel intensity of modern society. All our basic needs – and more – could be supplied with much less steel involved. For example, we could make cars lighter by making them smaller. That would bring energy savings without the need for energy-intensive high-grade steel. We could replace cars with bicycles and public transportation so that more people share less steel. Such changes would also reduce the need for steel in the road network, the energy infrastructure, and the manufacturing industry. We would need fewer machine tools, shipping containers, and reinforced concrete buildings. Whenever steel intensity is reduced, the advantages cascade throughout the whole system. Preventing corrosion and producing steel more locally from local resources would also reduce energy use and emissions.1014
The continuous growth of the steel output – the increasing steel intensity of human society – makes sustainable steel production impossible. No technology can change that because it’s not a technological problem. Like forestry can only be sustainable if the wood demand does not exceed the wood supply, steel is sustainable or not depending on the balance between (scrap) supply and (steel) demand. We may not be able to escape the Iron Age, but we have an option to escape the catch-22 that inextricably links steel production with fossil fuels."
That's the goal, or the requirement, or the necessity, however you want to look at it. It's not possible to know how everything is going to work after that before that; any quick perusal of how things changed in terms of domestic economy as the result of either world war will make that obvious.
No one will do that while military power rests on being able to burn oil.
@breadandcircuses
Surprisingly the article makes no mention of Iceland and Norway.
Between them they are the largest producers of aluminium in Europe and as close to carbon neutral as possible.
Both use renewable energy sources for the smelting process.
Steel production with renewable energy for arc furnaces (perfect for recycled steel) is a possibility.
The only reason Wales was a steel making centre was its proximity to coal mines. Same with Sheffield.
@breadandcircuses Molten Oxide Electrolysis can be used to produce virgin steel electrolytically from iron in a process similar to how aluminum is produced from bauxite.
Unfortunately, the planned switch to low-carbon energy sources and the electrification of heating and transport technologies will not decrease our dependency on the steel industry – on the contrary. A low-carbon power grid requires much more steel (and other materials) than an infrastructure based on fossil fuels. Wind and solar power are very diffuse power sources compared to fossil fuels. Therefore, it takes much more materials (and land) to produce the same energy. In jargon, wind and solar have low “power density” or high “material intensity.”2829303132
A low-carbon power grid requires much more steel than an infrastructure based on fossil fuels.
The “steel intensity” of thermal gas and coal power plants is between 50 and 60 tonnes of steel per megawatt of installed power.33 Hydroelectric power plants have a lower steel intensity, with 20-30 tonnes of steel per MW.733 Atomic power’s steel intensity is also lower at between 20 and 40 tonnes of steel per installed MW.3334 On the other hand, solar PV requires between 40 and 170 tonnes of steel per installed MW.3335 Although there is little or no steel in the solar panels themselves, it’s the material of choice for the structures that support them.
Steel and wind power
The most steel-intensive power source – by far – is the modern wind turbine. The steel intensity of a wind turbine depends on its size. A single, large wind turbine requires significantly more steel per megawatt of installed power than two smaller wind turbines.36 For example, a 3.6 MW wind turbine with a 100-meter tall tower requires 335 tons of steel (83 tons/MW), while a 5 MW wind turbine with a 150-meter tall tower needs 875 tons of steel (175 tons/MW).37 The trend is towards taller wind turbines and a higher steel intensity.
Steel consumption further increases for offshore wind turbines. Onshore wind power plants rely on reinforced concrete for their foundations, but offshore wind turbines need massive steel structures such as monopiles and jackets.38 The steel intensity for offshore wind turbines is calculated to be around 450 tonnes per MW for a 5 MW turbine – eight times higher than the steel intensity of a thermal power plant.36. As these wind turbines get taller and move into deeper waters, their steel use further increases.
The most popular offshore wind turbine nowadays has a capacity of 7 MW, while the largest ones have a capacity of 14 MW.36 If we make a conservative estimate based on the data above (the steel intensity doubles for every doubling of the power capacity), a 14 MW offshore wind turbine would require 1,300 tons of steel per MW or 18,200 tonnes in total. Such a wind turbine thus consumes 24 times more steel than a coal or gas power plant of the same power capacity.
Power transmission infrastructure
The data above only include the steel used in the power plants themselves. For fossil fuel power plants, they do not include the steel used in the pipelines, oil rigs, coal excavators, and the like. However, the same goes for the low-carbon power sources. Because they need much more resources than thermal power plants (steel but also other metals and materials), they depend on a global mining and transport infrastructure that is just as steel-intensive as the supply chain for fossil fuels.
Furthermore, because they are more diffuse power sources with intermittent and unpredictable power production, often located far away from energy consumption centers, renewable power plants drive the expansion of transmission infrastructure. That infrastructure is also based on steel – from switchyard equipment over towers to conduction cables.282930313242
Finally, low-carbon power sources also have a high need for special grades of steel, which are more energy-intensive to produce. Steel for off-shore wind turbines should resist corrosion, and stainless steel is increasingly used for solar panel support structures.43 Electrical lamination steel (iron-silicon) is indispensable for transformers in the power network.7 Nuclear power plants may have a relatively low steel intensity but are completely built up of energy-intensive specialty steels. For example, cladding the fuel elements containing fissionable uranium requires zirconium steel, while all structural elements contain austenitic stainless steel.
"The continuous growth of the steel output – the increasing steel intensity of human society – makes sustainable steel production impossible. No technology can change that because it’s not a technological problem. Like forestry can only be sustainable if the wood demand does not exceed the wood supply, steel is sustainable or not depending on the balance between (scrap) supply and (steel) demand."
@breadandcircuses 1st off, how to I see, the other replies to your post? As for the article itself, I think he is missing some technical points. His mention of arc furnaces, he mentioned the electricity coming from solar, wind or atomic power. Aluminium production uses electricity, and the plants are sited close to either large hydro-plants or nuclear plants. Such as the Wylfa nuclear power station in Anglesey. Which had problems, even before commissioning. The electric arc furnaces, are usually for smaller batches of specialist steels. Of the type needed in nuclear and thermal power stations, as well as CCS and hydrogen plants. He determines that solar and wind have a larger steel intensity, than nuclear and thermal. When nuclear, especially requires tonnes of reinforced concrete and specialist steels in their construction, plus all the infrastructure, to transmit electricity, the large cooling water system, refuelling and nuclear waste handling. Then there is the fact, large thermal plants, cannot be suddenly started or shut-down, so continue to burn fossil-fuels, even when there is low demand. With nuclear, even when shut-down, the cooling systems have to remain running to stop a melt-down. As for wind, such as the blades, a UK was developing blades constructed from bamboo. But, because of a lack of commitment by Blair/Brown's Labour Government, the company was taken over by foreign company.
@breadandcircuses seems like a good article, though I’m a bit surprised that in the conclusion, the proposed reductions in steel usage are all from usages that were deemed to be, if not negligible, very much the minority in the beginning of the article. There is also quite a bit of hand-waving about the dependency chains in the later parts of the article, when dismissing possible solutions, though it could be correct, it makes it easier to ignore by people invested in them.
@breadandcircuses 1/ I'm not an expert, but it seems that the author arily dismisses low-carbon steel making:
"Consequently, hydrogen-based steelmaking requires roughly ten times more wind turbines and solar panels than scrap-based steel production – and thus ten times more steel."
True, but so what? That's not 10x more energy than now, it's 10x more energy than a small slice of a hypothetical ideal economy where all steel is recycled from scrap.