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How to Escape From the Iron Age?

Mon, 18 Mar 2024 00:00:00 +0000

Image: Steel rebar construction for the concrete foundation of a wind turbine in Gilliam County, US. Image by Goose Chap, Wikimedia Commons (CC BY-SA 4.0)

Trapped in the Iron Age

In 1836, Danish antiquarian and curator Christian Jürgensen Thomsen distinguished three prehistorical eras based on the dominant materials used for weapons and cutting implements: the Stone Age, the Bronze Age, and the Iron Age.¹ Thomsen’s classification refers to the past, but according to his criteria, we have never evolved beyond the Iron Age. Even in the 21st century, iron remains the dominant material, not just for weapons and cutting implements but for about every modern technology.

We now use most iron in the form of steel. However, according to Thomsen’s criteria, we cannot speak of a “Steel Age.” First, steel is merely an alloy of iron (>98%) and carbon (<2%). Second, humans have been producing steel since the beginning of the Iron Age. That is a little-known fact in the Western world, where steel production only took off in the nineteenth century with fossil fuels. However, Asian and African metallurgists developed high-quality steels much earlier, and this knowledge eventually allowed Europeans to do the same – on a much larger scale.²

By 2021, the global iron and steel output reached 1,950 million tonnes (Mt). That is 22 times larger than the combined aluminum and copper output (88 Mt). The global iron and steel output corresponds to five times the global plastics output (391 Mt) and dwarfs the worldwide production of silicon (8.5 Mt) and lithium (0.1 Mt).³⁴ Steel is the fundamental material of industrial societies. Without plastics, lithium, or silicon, we would still be in an industrial society. Without iron and steel, we would be thrown back 3,000 years into the Bronze Age.

Where is all that steel?

The massive presence of steel in industrial society is not so obvious.⁵ At home, we find several steel appliances such as the refrigerator, washing machine, water boiler, bathtub, and cooking, heating, and cooling appliances. However, only 2-3% of total steel production ends up in domestic appliances.⁶⁷⁸ Outdoors, there’s a lot of steel in the form of vehicles. These are especially passenger cars that use around 10% of all steel globally (20% in rich countries). Busses, trucks, trains, and ships add another 4-5%. Altogether that is still less than 20% of the global steel output.

Most steel is embedded in other materials, located underground, or far away from residential areas.

Most steel is embedded in other materials, located underground, or far away from residential areas. More than half of global steel production goes into construction, which includes buildings (residential, commercial, industrial) and infrastructures (bridges, tunnels, harbors, canals, runways, oil rigs, refineries, pipelines, power plants, transmission lines, railways, subways, and so on). Much of that steel is embedded in concrete. Reinforced concrete is the world’s primary building material, and concrete is the only material that can match the output of steel (1,819 Mt in 2021).

Roughly 15% of global steel production serves to make machinery, including machine tools, industrial equipment, electrical hardware, and construction, mining, and farming machines. Even products made of other materials – such as other metals, plastics, and wood – are shaped by steel tools.⁵ The final 15% of steel production ends up in a variety of objects, from screws over food packaging to furniture and shipping containers.⁶⁷⁸

Image: Reinforced concrete is the world’s primary building material. Hole on Interstate 84, US. Image by Tony George, Oregon Department of Transportation, Wikimedia Commons (CC BY 2.0).

The environmental footprint of the steel industry

Steel is often presented as one of the most sustainable materials. Unlike plastics, steel can be recycled without any loss in quality. The steel industry has made great advances in energy efficiency, more so than many other industries. Making one ton of crude steel now requires roughly 20 gigajoules (GJ) of primary energy on average – three times less than in 1950.⁹ This compares very favorably to other materials such as aluminum (175 GJ/t), plastics (80-120 GJ/t), or copper (45 GJ/t).⁷ Unlike plastics, steel is a biodegradable material.¹⁰ Finally, iron ore is not in short supply. It makes up 5 percent of the Earth’s crust and is fourth in abundance among the elements.¹¹ For comparison, copper only makes up 0.01%.⁵

However, despite all these advantages, the global iron and steel industry consumes more energy and produces more carbon emissions than any other industry. The total primary energy use of crude steel production was 39 exajoules (EJ) in 2021, which corresponds to 7% of all energy used worldwide in that year (595 EJ). The greenhouse gas emissions are even higher because around 75% of energy use comes from coal – the fuel with the highest carbon emissions. In 2021, the iron and steel industry produced 3.3 Gt of carbon emissions, roughly 9% of global emissions (36.3 Gt).¹² The concrete industry follows closely with 8%.

The iron and steel industry consumes more energy and produces more carbon emissions than any other industry.

The estimates above come from the World Steel Association and the International Energy Agency. These data are available for all metals and have been documented over a long period, allowing for historical comparisons. However, they only refer to the smelting of the metal. They do not include the energy use and carbon emissions for mining and transporting iron ore, coal, limestone, scrap, and steel products. Nor do they include the energy and emissions for coke production and ore preparation – all essential to the steel production process.⁷

Scientific studies that have set wider boundaries for the iron and steel industry conclude that the energy cost of steel production increases by 50% to 100%.¹³ One report concludes that the methane emissions from metallurgical coal mining alone could increase emissions by 27%. Another study estimates that seaborne transport of iron ore and steel adds 10-15% extra emissions.¹⁴¹⁵ Iron and steel production also create other environmental problems, such as high water use, solid waste production, and significant air and water pollution.

The carbon footprint of the iron and steel industry is incompatible with current ambitions to eliminate net carbon emissions by 2050, even less so because steel production is very likely to expand further. Steel production grew tenfold since 1950 and doubled between 2000 and 2020, growing faster than many researchers had predicted.¹⁶ Furthermore, efficiency gains have decreased, and there is a scientific consensus that current technologies have reached their thermodynamic limits.⁷⁹¹⁷ During the last two decades, the average energy use for the production of 1 ton of steel has remained around 20 GJ/t.⁹¹⁸

How to make steel without fossil fuels?

There are two ways to make steel, and one is much more sustainable than the other.¹⁹ On the one hand, there is the blast furnace or basic oxygen furnace, in which steel is made from iron ore and coal. This technology is – in its essential form – 2000 years old. On the other hand, there is the electric arc furnace, in which steel is made from steel scrap and electricity. The electric arc furnace, which is a relatively new technology, consumes much less energy than the blast furnace, makes use of a recycled resource (no need to mine iron ore), and works without the direct use of coal or other fossil fuels (the electricity can be supplied by solar, wind, or atomic power).

The most energy-efficient electric arc furnaces now consume less than 300 kilowatt-hours of electricity per ton of steel produced.⁹²⁰ Hypothetically, if we had produced all steel in 2021 (1,950 Mt) in such furnaces, the total power consumption of the global iron and steel industry would have been only 585 terawatt-hours (Twh). That corresponds to just one-third of all electricity generated by wind turbines worldwide in the same year (1,848 Twh). Unfortunately, more than 70% of global steel output was made in blast furnaces fed by coal and iron ore.⁹²⁰ A blast furnace consumes twenty times more energy and cannot be operated by electricity because coal is both the fuel source and the chemical reductant. The combustion of coal produces carbon monoxide that reduces the iron from its ore.⁷

Not enough scrap available

The solution seems obvious: let’s produce all that steel in electric arc furnaces. However, this is impossible. There’s not enough scrap available: the continuous growth of the global steel output makes a circular flow of resources impossible.²¹ It takes decades before most steel becomes available for recycling. For example, there is 543 Mt of steel stocked in ships.²² The scrap available for recycling in 2021 corresponds to the production level of 1965 when global steel production was less than one-quarter of what it is today (450 Mt).⁹¹⁰¹⁵²³ Consequently, the other three quarters need to be produced in blast furnaces using coal and freshly mined iron ore.

Image: Cars for scrapping at the Port of Cardiff. Gareth James via Wikimedia Commons (CC BY-SA 2.0).

Nowadays, China produces roughly half of the steel in the world and does that almost exclusively (+90%) in blast furnaces using coal and iron ore. Many other steelmaking nations have a higher share of electric arc furnaces. However, it makes little sense to point the finger at China. First, the US and Europe have outsourced many of their industries to China since the 2000s, a trend that corresponds neatly with the growing steel output in that country. Furthermore, twenty to forty years ago, China hardly used any steel. Consequently, there is almost no scrap available. China has no other choice than to use blast furnaces.²⁴

Ever higher grades of steel

A second obstacle is the continuous development of higher grades of steel. There are now over 2,500 different types of steel with a variety of properties, such as increased strength, tolerance to high temperatures, or corrosion resistance.⁷⁹²³²⁵ Although these higher quality steels can be produced in electric arc furnaces, they are not made from scrap, and they have much higher energy use.

Steel available for recycling forms a mix of steel grades. That mix is suitable for making plain carbon steel but not highly alloyed steels, which require scrap with similar qualities. However, that scrap is not available. For example, stainless steel, the most produced special steel grade, has a recycling rate of only 15%. Almost 60 Mt of stainless steel was produced in 2021, compared to only 4 Mt in 1980.²⁶ The traditional use of stainless steel was in cutlery, surgical tools, and medical and food processing equipment. However, it is now also used in the construction of tunnels and outdoor furniture, wastewater treatment, seawater desalination, nuclear engineering, and the production of biofuels.⁷

The low recycling rate and the need for the extraction of additional elements such as chrome and nickel make higher grades of steel more energy-intensive to produce. For example, stainless steel production requires almost 80 GJ per ton, four times more than the production of plain carbon steel.⁷²³ The continuous development of higher-grade steels is stimulated by environmental legislation (such as the use of lighter steel in cars) and by competition from other materials, mainly aluminum and plastic composites.⁷⁹²³²⁵ Ironically, the competition with these materials, which consume even more energy, makes steel less and less sustainable.

Steel and renewable energy

The steel industry is heavily dependent on the energy supply, but the energy supply is also heavily dependent on the steel industry. Almost 10% of the global steel output goes into building and maintaining energy supply infrastructure. That amount corresponds to the entire steel output in 1950. A great share of that steel goes to gas and oil infrastructure.²⁷. Oil and gas mining, production, and transportation require steel for offshore drilling platforms, pipelines, refineries, tankers, and storage tanks. Coal mining depends on steel for cutters, loaders, conveyors, excavators, and trucks.⁷

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.

Image: Steel towers for wind turbines in the port of Rotterdam. Image: Melle Smets.

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.

Shorter life expectancy

The difference between renewable power sources and fossil fuels becomes even larger if the steel intensity is calculated per unit of energy rather than power (MWh instead of MW). In contrast to coal and gas power plants, the output of wind and solar power plants depends on the weather, and they do not always produce their maximum power capacity. Therefore, replacing 1 MW of fossil electricity generation capacity requires the installation of (on average) 4 MW of solar power or 2 MW of wind power.³⁹ A 14 MW offshore wind turbine thus has a steel intensity that is almost 50 times higher than a fossil fuel power plant for every kilowatt-hour of electricity produced.⁴⁰

A 14 MW offshore wind turbine has a steel intensity that is almost 50 times higher than a fossil fuel power plant for every kilowatt-hour of electricity produced.

Solar and wind power plants also have shorter lifetimes (20-30 years) compared to thermal power plants (30-60 years).³¹ While this does not affect the steel intensity per MW of power installed, it again increases the steel intensity per unit of energy produced over time. That does not always lead to a doubling of steel use because foundations for offshore wind turbines and structures for solar panels may have longer lifetimes than the power sources they support and could thus be reused.⁴¹

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.⁷⁴⁴

Low carbon grid cannot be made from recycled steel

The high steel intensity of low carbon power sources confronts us with a so-called “catch-22”, a situation in which there seems to be no escape from a problem no matter what we do. We need much more steel if we replace thermal power plants with renewable ones. Because there is not enough steel scrap available, we can only produce that extra steel from iron ore in blast furnaces burning fossil fuels. To address climate change, we need to build low-carbon sources quickly and in great numbers. However, to achieve circular material flows and build low-carbon power sources from scrap and renewable electricity, we would have to do the opposite: slow down the development of a low-carbon power grid.

Image: Steel foundations for off-shore wind turbines. Image by Glen Wallace, Wikimedia Commons (CC BY 2.0).

A well-cited study from 2013 concluded that if wind and solar power would supply 25,000 Twh of electricity – which corresponds to total global electricity demand in 2021 – we need about 3,200 Mt of steel to build the power plants alone.³³⁴⁵ Global electricity demand is projected to grow to between 52,000 and 71,000 terawatt-hours in 2050, which would increase the extra steel demand to between 6,400 and 8,960 Mt.⁴⁶ Spread out over the lifetime of solar panels and wind turbines (25 years), we would have to produce 256 to 358 Mt extra steel per year to make wind turbines and solar panel structures – comparable to the steel demand for passenger cars (195 Mt) and other transportation modes (98 Mt) combined.

That is still a very optimistic estimation. Electricity demand only makes up around 20% of total energy demand. If the total energy demand (177,000 Twh in 2021) would be supplied by wind and solar, we would need 22,400 Mt of steel. That’s an extra 896 Mt steel per year – as much as the global production in the early 2000s. You could argue that electricity can be used more efficiently than fossil fuels, for example, in cars and heating systems. However, at the same time, total energy demand is expected to rise further, countering the gains made by increased energy efficiency.

The high-tech solutions

The steel industry counts on technological solutions to make steel production carbon neutral. One option is to replace coal by gas, an approach that is already common in the Middle East and North America. Gas-based steelmaking results in somewhat lower carbon emissions, but they are still much higher than in the case of the electric arc furnace. Therefore, most attention goes to hydrogen, which can replace purified coal (coke) as a reducing agent in a direct reduction shaft furnace.⁴⁷ However, hydrogen-based steelmaking does not offer an escape from the catch-22 because it further increases the need for a steel-intensive infrastructure.

The production of hydrogen is energy-intensive. It takes 50-55 kilowatt-hour to make 1 kg of hydrogen and 60 kg of hydrogen to make 1 ton of steel.⁴⁷ The production of 1 ton of steel from hydrogen thus consumes 3,000 kWh of electricity, which is ten times higher than the electricity use of an electric arc furnace making steel from scrap. 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. On top of this comes the steel for building the pipelines and storage tanks that are part of the hydrogen infrastructure.

Image: Worker in a blast furnace. Bundesarchiv, B 145 Bild-F079044-0020 / CC-BY-SA 3.0.

Carbon capture and storage, in which the carbon emissions of steelmaking plants are captured and then stored underground, faces the same problems. It requires a steel infrastructure and extra energy, thus indirectly raising the use of fossil fuels. Reverting to older, preindustrial steelmaking processes is not the answer either. Today’s blast furnace is essentially still the blast furnace from earlier centuries, only much more energy efficient.⁷

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.⁴⁹

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Forthcoming article, Kris De Decker, Low-tech Magazine. Subscribe to Low-tech Magazine’s newsletter. ↩︎
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See, for example: Hatayama, Hiroki, et al. “Outlook of the world steel cycle based on the stock and flow dynamics.” Environmental science & technology 44.16 (2010): 6457-6463. This paper predicted steel demand to reach 1.8 billion tonnes only by around 2025. ↩︎
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About 5% of global steel is produced by a third method: gas-based direct iron reduction. These furnaces use gas instead of coal and have therefore lower carbon emissions. However, emissions are still much higher than in the case of the electric arc furnace. Gas-based steelmaking mainly happens in the Middle East and North America. ↩︎
He, Kun, and Li Wang. “A review of energy use and energy-efficient technologies for the iron and steel industry.” Renewable and Sustainable Energy Reviews 70 (2017): 1022-1039. This source gives a value of 1-1.5 GJ/ton of crude steel. ↩︎ ↩︎
This also holds true for many other materials. See: “How circular is the circular economy?”, Kris De Decker, Low-tech Magazine, November 2018. https://qelnixcor.cloud/2018/11/how-circular-is-the-circular-economy/ ↩︎
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In the West, the expansion of steel use happened over a period of 150 years, in tandem with technological evolution. In contrast, China compressed this technological evolution in just a few decades: shipping and railways, electrification, steel buildings, the car and the airplane, the internet, and renewable power technologies. There are still large parts of the world where the steel intensity of society is very low, such as India and Africa. There is thus still a lot of room for the growth of the steel output. Source: Smil, Vaclav. Still the iron age: iron and steel in the modern world. Butterworth-Heinemann, 2016. ↩︎
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Gervásio, Helena, et al. “Comparative life cycle assessment of tubular wind towers and foundations–Part 2: Life cycle analysis.” Engineering structures 74 (2014): 292-299. & Rebelo, Carlos, et al. “Comparative life cycle assessment of tubular wind towers and foundations–Part 1: Structural design.” Engineering structures 74 (2014): 283-291. ↩︎
Assessing the significance of steel to the global wind industry, S&P Global, Commodity Insights. December 2021. https://www.spglobal.com/commodityinsights/en/ci/research-analysis/assessing-the-significance-of-steel-to-the-global-wind-industry.html ↩︎
Bolson, Natanael, Pedro Prieto, and Tadeusz Patzek. “Capacity factors for electrical power generation from renewable and nonrenewable sources.” Proceedings of the National Academy of Sciences 119.52 (2022): e2205429119. https://www.pnas.org/doi/10.1073/pnas.2205429119 ↩︎
This result corresponds well with Vidal, Olivier, Bruno Goffé, and Nicholas Arndt. “Metals for a low-carbon society.” Nature Geoscience 6.11 (2013): 894-896. The data are in the supplementary info: https://www.nature.com/articles/ngeo1993#Sec5 ↩︎
For off-shore wind turbines, the lifetime of the foundations is estimated to be 100 years, so in principle they could serve for replacement wind turbines of the same size. On the other hand, it is not self-evident that these steel foundations will eventually be recycled. First, only around 10% of decommissioning costs can be recovered by recycling the metal, meaning that it is not economically and perhaps even energetically interesting to do it. Second, in some cass marine life has flourished around the foundations. The four offshore wind farms that had been decomissioned in 2019 lasted for 15, 18, 20 and 26 years. Source: Topham, Eva, et al. “Recycling offshore wind farms at decommissioning stage.” Energy policy 129 (2019): 698-709. ↩︎
See https://www.fedsteel.com/insights/steels-role-in-the-us-power-infrastructure/ ↩︎
See https://industry.arcelormittal.com/products-solutions/Products_in_the_spotlight/magnelis ↩︎
Maziasz, Philip J., and Jeremy T. Busby. Properties of austenitic stainless steels for nuclear reactor applications. Oak Ridge National Lab.(ORNL), Oak Ridge, TN (United States), 2012. ↩︎
Part of this has already been built. The researchers start from the solar and wind power production in 2013, which was 400 Twh, while both power sources produced 2,894 Twh in 2021. ↩︎
Electricity consumption worldwide from 2000 to 2022, with a forecast for 2030 and 2050, by scenario. Statista. https://www.statista.com/statistics/1426308/electricity-consumption-worldwide-forecast-by-scenario/#:~:text=According%20to%20a%20recent%20forecast,on%20the%20energy%20transition%20scenario ↩︎
Bhaskar, Abhinav, et al. “Decarbonizing primary steel production: Techno-economic assessment of a hydrogen based green steel production plant in Norway.” Journal of Cleaner Production 350 (2022): 131339. ↩︎ ↩︎
Scrap use in the steel industry, World Steel Association. May 2021. https://worldsteel.org/wp-content/uploads/Fact-sheet-on-scrap_2021.pdf ↩︎
Another motivation for reducing the steel intensity of modern society is to limit the consequences of geopolitical conflicts. The more steel we produce for peaceful purposes, the more steel becomes available for war and destruction. Remarkably, the production of military equipment is absent from modern steel statistics, and if mentioned, its share is very low. However, in times of war, steelmaking facilities switch to producing steel for military purposes. The steel industry can thus be converted into a weapons industry at any moment, and there is now a lot more steel production capacity available than there has ever been in history. ↩︎

How Circular is the Circular Economy?

Sat, 03 Nov 2018 00:00:00 +0000

Image: Illustration by [Diego Marmolejo](https://www.behance.net/diegomarmolejo).

The circular economy – the newest magical word in the sustainable development vocabulary – promises economic growth without destruction or waste. However, the concept only focuses on a small part of total resource use and does not take into account the laws of thermodynamics.

Introducing the Circular Economy

The circular economy has become, for many governments, institutions, companies, and environmental organisations, one of the main components of a plan to lower carbon emissions. In the circular economy, resources would be continually re-used, meaning that there would be no more mining activity or waste production. The stress is on recycling, made possible by designing products so that they can easily be taken apart.

Attention is also paid to developing an “alternative consumer culture”. In the circular economy, we would no longer own products, but would loan them. For example, a customer could pay not for lighting devices but for light, while the company remains the owner of the lighting devices and pays the electricity bill. A product thus becomes a service, which is believed to encourage businesses to improve the lifespan and recyclability of their products.

The circular economy is presented as an alternative to the “linear economy” – a term that was coined by the proponents of circularity, and which refers to the fact that industrial societies turn valuable resources into waste. However, while there’s no doubt that the current industrial model is unsustainable, the question is how different to so-called circular economy would be.

Several scientific studies (see references) describe the concept as an “idealised vision”, a “mix of various ideas from different domains”, or a “vague idea based on pseudo-scientific concepts”. There’s three main points of criticism, which we discuss below.

Too Complex to Recycle

The first dent in the credibility of the circular economy is the fact that the recycling process of modern products is far from 100% efficient. A circular economy is nothing new. In the middle ages, old clothes were turned into paper, food waste was fed to chickens or pigs, and new buildings were made from the remains of old buildings. The difference between then and now is the resources used.

Before industrialisation, almost everything was made from materials that were either decomposable – like wood, reeds, or hemp – or easy to recycle or re-use – like iron and bricks. Modern products are composed of a much wider diversity of (new) materials, which are mostly not decomposable and are also not easily recycled.

For example, a recent study of the modular Fairphone 2 – a smartphone designed to be recyclable and have a longer lifespan – shows that the use of synthetic materials, microchips, and batteries makes closing the circle impossible. Only 30% of the materials used in the Fairphone 2 can be recuperated. A study of LED lights had a similar result.

The large-scale use of synthetic materials, microchips, and batteries makes closing the circle impossible.

The more complex a product, the more steps and processes it takes to recycle. In each step of this process, resources and energy are lost. Furthermore, in the case of electronic products, the production process itself is much more resource-intensive than the extraction of the raw materials, meaning that recycling the end product can only recuperate a fraction of the input. And while some plastics are indeed being recycled, this process only produces inferior materials (“downcycling”) that enter the waste stream quickly afterwards.

The low efficiency of the recycling process is, on its own, enough to take the ground from under the concept of the circular economy: the loss of resources during the recycling process always needs to be compensated with more over-extraction of the planet’s resources. Recycling processes will improve, but recycling is always a trade-off between maximum material recovery and minimum energy use. And that brings us to the next point.

How to Recycle Energy Sources?

The second dent in the credibility of the circular economy is the fact that 20% of total resources used worldwide are fossil fuels. More than 98% of that is burnt as a source of energy and can’t be re-used or recycled. At best, the excess heat from, for example, the generation of electricity, can be used to replace other heat sources.

As energy is transferred or transformed, its quality diminishes (second law of thermodynamics). For example, it’s impossible to operate one car or one power plant with the excess heat from another. Consequently, there will always be a need to mine new fossil fuels. Besides, recycling materials also requires energy, both through the recycling process and the transportation of recycled and to-be-recycled materials.

To this, the supporters of the circular economy have a response: we will shift to 100% renewable energy. But this doesn’t make the circle round: to build and maintain renewable energy plants and accompanied infrastructures, we also need resources (both energy and materials). What’s more, technology to harvest and store renewable energy relies on difficult-to-recycle materials. That’s why solar panels, wind turbines and lithium-ion batteries are not recycled, but landfilled or incinerated.

Input Exceeds Output

The third dent in the credibility of the circular economy is the biggest: the global resource use – both energetic and material – keeps increasing year by year. The use of resources grew by 1400% in the last century: from 7 gigatonnes (Gt) in 1900 to 62 Gt in 2005 and 78 Gt in 2010. That’s an average growth of about 3% per year – more than double the rate of population growth.

Growth makes a circular economy impossible, even if all raw materials were recycled and all recycling was 100% efficient. The amount of used material that can be recycled will always be smaller than the material needed for growth. To compensate for that, we have to continuously extract more resources.

Growth makes a circular economy impossible, even if all raw materials were recycled and all recycling was 100% efficient.

The difference between demand and supply is bigger than you might think. If we look at the whole life cycle of resources, then it becomes clear that proponents for a circular economy only focus on a very small part of the whole system, and thereby misunderstand the way it operates.

Accumulation of Resources

A considerable segment of all resources – about a third of the total – are neither recycled, nor incinerated or dumped: they are accumulated in buildings, infrastructure, and consumer goods. In 2005, 62 Gt of resources were used globally. After subtracting energy sources (fossil fuels and biomass) and waste from the mining sector, the remaining 30 Gt were used to make material goods. Of these, 4 Gt was used to make products that last for less than one year (disposable products).

Image: Illustration by [Diego Marmolejo](https://www.behance.net/diegomarmolejo).

The other 26 Gt was accumulated in buildings, infrastructure, and consumer goods that last for more than a year. In the same year, 9 Gt of all surplus resources were disposed of, meaning that the “stocks” of material capital grew by 17 Gt in 2005. In comparison: the total waste that could be recycled in 2005 was only 13 Gt (4 Gt disposable products and 9 Gt surplus resources), of which only a third (4 Gt) can be effectively recycled.

About a third of all resources are neither recycled, nor incinerated or dumped: they are accumulated in buildings, infrastructure, and consumer goods.

Only 9 Gt is then put in a landfill, incinerated, or dumped – and it is this 9 Gt that the circular economy focuses on. But even if that was all recycled, and if the recycling processes were 100% efficient, the circle would still not be closed: 63 Gt in raw materials and 30 Gt in material products would still be needed.

As long as we keep accumulating raw materials, the closing of the material life cycle remains an illusion, even for materials that are, in principle, recyclable. For example, recycled metals can only supply 36% of the yearly demand for new metal, even if metal has relatively high recycling capacity, at about 70%. We still use more raw materials in the system than can be made available through recycling – and so there are simply not enough recyclable raw materials to put a stop to the continuously expanding extractive economy.

The True Face of the Circular Economy

A more responsible use of resources is of course an excellent idea. But to achieve that, recycling and re-use alone aren’t enough. Since 71% of all resources cannot be recycled or re-used (44% of which are energy sources and 27% of which are added to existing stocks), you can only really get better numbers by reducing total use.

A circular economy would therefore demand that we use less fossil fuels (which isn’t the same as using more renewable energy), and that we accumulate less raw materials in commodities. Most importantly, we need to make less stuff: fewer cars, fewer microchips, fewer buildings. This would result in a double profit: we would need less resources, while the supply of discarded materials available for re-use and recycling would keep growing for many years to come.

It seems unlikely that the proponents of the circular economy would accept these additional conditions. The concept of the circular economy is intended to align sustainability with economic growth – in other words, more cars, more microchips, more buildings. For example, the European Union states that the circular economy will “foster sustainable economic growth”.

Even the limited goals of the circular economy – total recycling of a fraction of resources – demands an extra condition that proponents probably won’t agree with: that everything is once again made with wood and simple metals, without using synthetic materials, semi-conductors, lithium-ion batteries or composite materials.

References:

Haas, Willi, et al. “How circular is the global economy?: An assessment of material flows, waste production, and recycling in the European Union and the world in 2005.” Journal of Industrial Ecology 19.5 (2015): 765-777.

Murray, Alan, Keith Skene, and Kathryn Haynes. “The circular economy: An interdisciplinary exploration of the concept and application in a global context.” Journal of Business Ethics 140.3 (2017): 369-380.

Gregson, Nicky, et al. “Interrogating the circular economy: the moral economy of resource recovery in the EU.” Economy and Society 44.2 (2015): 218-243.

Krausmann, Fridolin, et al. “Global socioeconomic material stocks rise 23-fold over the 20th century and require half of annual resource use.” Proceedings of the National Academy of Sciences (2017): 201613773.

Korhonen, Jouni, Antero Honkasalo, and Jyri Seppälä. “Circular economy: the concept and its limitations.” Ecological economics 143 (2018): 37-46.

Fellner, Johann, et al. “Present potentials and limitations of a circular economy with respect to primary raw material demand.” Journal of Industrial Ecology 21.3 (2017): 494-496.

Reuter, Markus A., Antoinette van Schaik, and Miquel Ballester. “Limits of the Circular Economy: Fairphone Modular Design Pushing the Limits.” 2018

Reuter, M. A., and A. Van Schaik. “Product-Centric Simulation-based design for recycling: case of LED lamp recycling.” Journal of Sustainable Metallurgy 1.1 (2015): 4-28.

Reuter, Markus A., Antoinette van Schaik, and Johannes Gediga. “Simulation-based design for resource efficiency of metal production and recycling systems: Cases-copper production and recycling, e-waste (LED lamps) and nickel pig iron.” The International Journal of Life Cycle Assessment 20.5 (2015): 671-693.

The Mechanical Transmission of Power (2): Jerker Line Systems

Sat, 02 Feb 2013 00:00:00 +0000

Field motor on steel frame with steel jerker rods on the James Field. Image: "[Conservation district study appendix](http://www.lambtononline.ca/home/residents/planninganddevelopment/Oil%20Heritage%20Conservation%20District%20Plan%20Documents/Forms/AllItems.aspx)", Oil Heritage Conservation District Plan, The Corporation of the County of Lambton.

From the 1860s to 1940s, many oil wells were pumped by a technology that originates in a sixteenth-century power transmission system used in the mining industry.

One engine operated up to 45 pumps in different locations, each up to a mile away. Power was transmitted by means of wooden rods or steel cables that moved back and forth, snaking through the landscape.

The system was so efficient that an engine used for pumping an oil well could operate a whole cluster of pump jacks. The technology, which still operates in a handful of small oil fields, could also work with renewable energy sources, and shows great potential for efficient small-scale energy use.

Jerker line systems can be used to operate water pumps or sawing machines, to forge iron, to process food or fibres, or to make paper.

From the 1500s onwards, engineers developed mechanical power transmission and distribution systems that became ever more sophisticated: Stangenkunsten. Networks of pivoted, wooden field-rods conveyed power from waterwheels in the valleys to mining machinery in the mountains over distances of up to 4 km, operating pumps and bellows, hoisting ores, and transporting miners up and down shafts.

Steam engines, which started replacing water wheels from the 1860s onwards, were not dependent on the proximity of a stream or river, and could thus be located close to the mine shaft. This eliminated the need for mechanical power transmission. However, the Stangenkunst did not disappear. On the contrary, the technology became even more popular after, rather than before, the invention of the steam engine.

For one, it found a new application in oil production, initially in the United States but later all over the world. It was in the oil industry that the Stangenkunst reached the pinnacle of its development, and became known as the “jerker line system”.

The Canadian Jerker Line System

Right from the start of modern oil production in the late 1850s, the Stangenkunst played an important role. It was first used for pumping oil in Oil Springs, Ontario, Canada. While the oil here was of very good quality, production was marginal. The high cost of operating a steam engine at each was not economically viable. In 1863, only four years after the industry came into production, a solution was found by John Henry Fairbank, who set up a system for the transfer of power from a steam engine to multiple oil pumps.

A Stangenkunst in Oil Springs, Ontario, Canada. Image: [Markus Wandel](http://wandel.ca/).

The method, which became known as the “Canadian Jerker Line System”, was remarkably similar to the Stangenkunsten. Fairbank used wooden rods, which swung back and forth from wooden hangers that were suspended from wooden poles, and connected to wooden pump jacks. He didn’t even bother to apply the more efficient pantograph system developed in the 1590s, but used the original single-rod system. This made sense: it was cheaper to build, and friction was less of a problem since the system aimed at distributing power rather than transferring it long-distance (most oil pumps were within one mile of the central power source).

Subdividing and Distributing Power

There were some differences between the Fairbank method and the pre-industrial Stangenkunsten. Two cranks converted the circular motion of the steam engine’s wheel to a reciprocating motion that moved two parallel wooden rods back and forth, just as in the older systems powered by water wheels. In Fairbank’s model, however, a mechanism was introduced to slow down the revolution speed of the steam engine. It consisted of a leather belt placed between the wheel of the steam engine and the cranks. Another addition was the bull wheel, a cast-iron wheel making back-and-forth quarter turns. It was housed in a timber frame just outside the engine shed.

A bull wheel in Oil Springs, Ontario. Source: \"[Conservation district study appendix](http://www.lambtononline.ca/home/residents/planninganddevelopment/Oil%20Heritage%20Conservation%20District%20Plan%20Documents/Forms/AllItems.aspx)", Oil Heritage Conservation District Plan, The Corporation of the County of Lambton.

The bull wheel allowed the reciprocating motion of the two cranks to be subdivided over a greater number of rod lines. In the picture above, for instance, power is distributed from the steam engine to the bull wheel via the two wooden rods on the lower left side. It is transferred to a double field line which runs diagonally from upper left to lower right (the main line) while a single rod line extends to the centre and back of the picture. Thus, in this case, five rod lines branch off from the central power instead of one or two.

A field wheel in Oil Springs, Ontario. Source: \"[Conservation district study appendix](http://www.lambtononline.ca/home/residents/planninganddevelopment/Oil%20Heritage%20Conservation%20District%20Plan%20Documents/Forms/AllItems.aspx)", Oil Heritage Conservation District Plan, The Corporation of the County of Lambton.

Additional subdivision of power to other field rods (branch lines) could happen further along the main line, by means of a “field wheel” — a similar cast-iron, oscillating wheel in a timber frame. The field wheel was also used for diverting a main rod line 90 degrees, as can be seen in the picture above. Field wheels replaced the “Kunst Kreuzen” or “Engine Crosses” used in pre-industrial Stangenkunsten.

V-shaped wooden assemblies, lying on their sides, were used to make less sharp turns. The point of the V was anchored, and acted as the pivot for the mechanism. When the jerker line pulled on one leg of the V, the lines comes from the other direction were pulled out, too. A similar V-rod placed upright was used to change direction in the vertical plane when the line crossed a hill or valley.

The Pennsylvania Jerker Line System

The Canadian jerker line system spread to other oilfields but was eventually superseded by a more sophisticated system in which steel cables and iron bars replaced wooden rods. The metal rods were usually called “shackle lines”. This method was developed in 1879 by Pennsylvania oilman Edward Yates and became known as the “Pennsylvania Jerker Line System”.

Pennsylvania jerker line system, Flat Rock, Illinois, US. Source: [Old Iron](http://www.herculesengines.com/FlatRock/).

The famous Pennsylvania oilfields (home to Rockerfeller’s Standard Oil Company) came into production around the same time as the Ontario oil fields. However, unlike in Canada, steam engines were used to power each well for the first two decades. Oil wells in the Allegheny Plateau had a high initial production, which was followed by a rapid drop off. The incentive for pumping these low production wells after their initial outflow was small, as new fields were continually being discovered and drillers would simply sink a new well.

In the late 1870s, following a decline in oil prices and production per well, economising the oil production process became key to profitability. This drive for efficiency resulted in the adoption of the jerker line system, which made using previously-abandoned wells economically viable again.

Pennsylvania jerker line system, Flat Rock, Illinois, US. Source: [Old Iron](http://www.herculesengines.com/FlatRock/).

By 1885, the jerker line system was used widely in Pennsylvania (then the largest oil producer in North America). Thereafter, it spread to other US oil fields. By the early twentieth century, the system was used in oil fields around the world. By then, the technology had improved and numerous oil-well supply companies had developed standardised systems that could be purchased in part or whole.

A schematic of a Pennsylvania jerker line system, showing both geared power and bandwheel power system. Drawing by Eric S. Elmer. Source: [Library of Congress](http://www.loc.gov/pictures/item/pa3551.sheet.00003a/resource/).

While the Canadian jerker line system was reminiscent of the Stangenkunsten operating in pre-industrial times, the Pennsylvania jerker line system looked radically different. The prime mover (mostly a gas engine supplied from a nearby well) operated a “central power” (either geared or bandwheel) which slowed down the engine speed, converted the engine’s rotary motion to reciprocating motion, and distributed power to all the rod lines.

One Engine Powers 45 pumps

A back-and-forth motion was imparted to the rod lines by an “eccentric”, placed either above or below the geared or bandwheel power, to which 8 to 15 rod lines were hooked that fanned out in all directions. The eccentric was mounted slightly off-center from the power’s central vertical shaft, with the rod lines attached to the outer slip ring. As the eccentric rotated within the slip ring, the slip ring oscillated, pulling the rod lines. For each rotation of the slip ring, the rod lines completed one full stroke (see the illustration below).

Eccentric motion jerker

Typically, the mechanism produced 12 to 20 oscillations per minute, pulling the attached shackle lines an equal number of times. Depending on the number of wells, up to three eccentrics could be mounted on the central shaft, so that a total of 45 oil wells in different locations could be pumped. (More commonly, however, 10 to 25 pumps were powered as they wanted to limit the amount of temporarily unproductive wells in case of an engine breakdown.)

Implications for Field Layout

These different approaches to subdividing and distributing power led to distinct field layouts. In the Pennsylvania system, all oil pumps in the cluster were directly connected to the central power via jerker lines, which radiated out of the engine shed in all directions:

An axonometric view of the Lockwood Poer (built in 1909), near Warren, pennsylvania, showing the spatial relationship of machinery to structure inside a typical octagonal power. Drawing by Eric S. Elmer. Source: [Library of Congress](http://www.loc.gov/pictures/item/pa3551.sheet.00003a/resource/).

In the Canadian jerker line system, none of the pump jacks were directly connected to the central power. Motion was transferred to the bull wheel and then further subdivided along the main lines using field wheels. As a result, the Pennsylvania jerker line system generally produced web-like patterns, while the Canadian jerker line system usually created linear patterns with dendritic lines.

This can be seen clearly in the James Field in Ontario, which still has both systems still operating. The spider-like systems use metal rods, while the linear systems use wooden rods.

Inventory map of the James field with its well numbers, central powers and additional features. The spider-like systems use metal rods, while the linear systems use wooden rods. Source: "[Conservation district study appendix](http://www.lambtononline.ca/home/residents/planninganddevelopment/Oil%20Heritage%20Conservation%20District%20Plan%20Documents/Forms/AllItems.aspx)", Oil Heritage Conservation District Plan, The Corporation of the County of Lambton.

A Balanced system

The web-like layout of the Pennsylvania system offered an important advantage. Because a Stangenkunst was always a combination of horizontal and vertical power transmission, gravity delivered part of the power. A water wheel or steam engine had to deliver all the power needed to make the horizontal stroke that pulled the vertical mechanism upwards, but gravity aided the return stroke. In the case of oil pumping, the weight of the grasshopper pump made the return stroke, saving energy.

Pennsylvania jerker line system, Flat Rock, Illinois, US. Source: [Old Iron](http://www.herculesengines.com/FlatRock/).

This effect was doubled when each well was matched with one in the opposite direction. When the sucker rods in one well raised (the upstroke), those in the opposite well lowered under their own weight (the downstroke), helping raise the rods in the well undergoing the upstroke. In other words, the pumps were powering each other with their own weight. This minimized the load on the engine: the only power required was for overcoming inertia and friction, plus the weight of the oil lifted at each stroke.

Pennsylvania jerker line system, Flat Rock, Illinois, US. Image: [Old Iron](http://www.herculesengines.com/FlatRock/).

The web-like layout of the Pennsylvania system made balancing loads much easier. At all times, half the dead load of rods and mechanisms in the field was being lifted while the other half descended. The steel rods attached to the eccentric could be hooked to, or unhooked from, shackle lines that were connected to the oil pumps. If one well was disconnected, the well in the opposite direction was removed to maintain balance. If this was not possible, the eccentric rod of the disconnected well was hooked to a counterbalance. Since all pumps were directly connected to the central power, one worker could balance the load of all the wells.

Balancing a jerker line system

This made it possible for a cluster of about 15 to 30 oil wells to be pumped with almost the same engine capacity required to pump one well. In Surface Machinery and Methods for Oil-Well Pumping (1925), H.C. George writes:

“In the early days of the oil industry, all nonflowing wells were pumped individually “on the beam” by steam engines. This system wasted both labor and power, as each well required a man and a steam power plant. At present a group of 15 to 30 similar wells is pumped with a central “power” or “jack” plant with practically the same labor and the same energy capacity as was then used at each well.”

“Many oil wells if pumped individually would show a loss, but operated as members of a group they show a profit. The older fields of Pennsylvania, Ohio, West Virginia, and Illinois exemplify efficiency in group operation. In Pennsylvania the 59,000 operating oil wells show an average of less than a quarter of a barrel production per well per day, yet are being operated at a profit by the group method.”

“Wells of like characteristics, such as pumping time, length of stroke, and size of tubing should be balanced for best results. Some oil companies pump wells of like characteristics at the same time, then take those wells off the power and put on other wells of like characteristics. This practice is common in some of the eastern oil fields, where many wells do not pump more than a few hours per week, and where powers handle 15 to 30 wells, each pumped only several hours at a time.”

Shacklework

The use of steel cables instead of wooden rods also made it easier to navigate difficult terrain. The Pennsylvania jerker line system made use of a variety of devices to support the lines and change their direction – these were generally called “shacklework”. The steel cables were hung from tripods or supported by “friction posts”, which were fixed in the ground, or “rocking posts”, which were mounted on a pivoting base to allow a rocking motion. “Hold-ups” and “hold-downs” guided the lines up or down, while “butterflies” and “ring swings” allowed them to change direction in order to carry the lines around obstacles.

Pennsylvania jerker line system, Flat Rock, Illinois, US. Source: [Old Iron](http://www.herculesengines.com/FlatRock/).

A “butterfly” was a triangular wooden or metal frame, which allowed up to 90 degree turns and was reminiscent of the V-rods used in the Canadian and pre-industrial system. A “ring swing” was used for lesser changes in direction and was even simpler. It consisted of three rings: one large ring, attached to a another suitable mounting spot, and two smaller rings attached to the large ring and the shackle line. Pendulums and rockers were sometimes used to make the length of the stroke at the well differ from that imparted to the jerker line at the central power.

Often, the shacklework was made from recycled parts, such as discarded rods or pipes. In 1925, H.C. George wrote that “the power or jack plant, and the machinery, shackle line, and jack are all usually standard and purchased from oil-well supply companies, but the shackle line structures are usually designed and built by the operating oil company. This results in a multiplicity of designs and a variety of material.”

Images: Jerker line system supports.

In some American towns, shacklework from neighbouring oil fields rocked back and forth over streets and alleys.

Jerker Line Systems Still in Operation

The Pennsylvania jerker line system became the dominant technology used to pump secondary oil wells up till the 1940s, pumping wells up to 3,500 feet deep, and remained in use until the 1960s and 70s. A few installations are stilll running today, or operated until recently. Some of the pictures above and below (there are many more if you follow this link), show the last two oil leases in Flat Rock, Illinois, which used a central power source and rod lines of the Pennsylvania type.

Pennsylvania jerker line system, Flat Rock, Illinois, US. Source: [Old Iron](http://www.herculesengines.com/FlatRock/).

Each is run with a 35 horse power oil-engine and pumps 10 or 11 wells. The rods rest on wood stakes 15 to 20 feet apart and the power moves the rods about 40 cm back and forth. In some places, the rods are rigged to cross a creek or make a turn and head in a different direction. The systems were photographed in 2003, when they were still operational.

Most remarkable, however, are the central power systems in Oil Springs, Ontario, which have been in operation for 150 years now. Some of these oil fields still make use of the Canadian jerker line system, which was the original technology used to pump oil in the mid-nineteenth century when the fields came into production. Most of the lines on the Fairbank field, and some of the lines on the James field, use wooden rods that operate wooden pump jacks, while some lines on the James field, and all lines on the neighbouring fields, use the original Pennsylvania jerker line system.

Canadian jerker line system, Ontario. Source: [Markus Wandel](http://wandel.ca/).

While there are obviously sentimental reasons for using nineteenth and early twentieth century technology — the owner of the fields is a great-grandson of John Henry Fairbank, designer of the Canadian jerker line system — the site is not a museum, but a working field that is economically viable. Instead of holding on to the past and trying to recreate a historic oil field, the technology has been continuously improved to maintain its profitability.

More Efficient

One major change in the technology is that steam engines have been replaced by small electric motors, which are cheaper, more efficient and easier to maintain. Most are equipped with reduction gearing, which has made the bulky powerhouse mechanism redundant. Individually-powered pump jacks have replaced the central power system in locations where running a jerker line has failed to be cost-effective, but where the central power system is still in use, it is so because it remains the most efficient and economical.

Stangenkunst in Ontario, Canada. Source: [Markus Wandel](http://wandel.ca/).

Even the remaining wooden field rods have been improved: metal hangers that once supported the wooden jerker lines have been replaced with nylon rope for ease of maintenance. The wood for jerker lines and pump jacks is not original, of course, since it is exposed to the elements: the rebuilding of wood equipment has been an on-going historic process.

Canadian jerker line system, Ontario. Source: [Markus Wandel](http://wandel.ca/).

Oil extraction is usually thought to be large in scale and finite in its lifecycle. However, in Oil Springs, it has been conducted on a continuous, small-scale basis since the late 1850s, while all other oil fields from those times have long been pumped dry using much more powerful technology. One cannot help but wonder how the world would have looked like if all oilmen had stuck with nineteenth century technology.

Future Applications

The jerker line system has value, and could be very helpful for those looking for ways to live comfortably life without excessive energy use. The system in the picture below — which still operates today in Oil Springs — is one that any maker could bolt together quickly in no time. With this set-up, one small electric motor could operate four machines in different locations.

Why do this instead of powering each device individually? One: you save three electric motors. Two: there is no need to provide batteries or electric outlets at any of the locations. Three: you can balance the system so that one device helps power the other, saving a considerable amount of energy. The electric motor shown above can also be replaced by a windmill, a water wheel, a solar thermal plant, or a stationary bicycle. In these cases, you can distribute mechanical energy without conversion losses.

Although a Stangenkunst or jerker line system can only transfer mechanical energy via reciprocating motion, it has seen a remarkable variety of applications throughout its 450 years of operation: pumping (either oil or water), ventilation (operating bellows), processing ores (operating trip-hammers), and even transporting people and goods up and down shafts (operating man engines and bucket hoists). Reciprocating motion could also be used to operate sawing machines or, using trip-hammers, to forge iron, process food or fibres, or make paper.

Sources:

“Surface Machinery and Methods for Oil-Well Pumping”, H.C. George, Bulletin 224, Bureau of Mines, Department of Interior, 1925.
“Oil Heritage Conservation District Plan Documents”, The Corporation of the County of Lambton, 2010.
“Historic American Engineering Record; Addendum to Allegheny National Forest Oil Heritage” (PDF), HAER No. PA-436, Michael W. Caplinger, 1997
“Allegheny Oil Powers: Documenting Endangered Cultural Resources in Allegheny National Forest”, Christopher Marston, 2000
“Technology on the Frontier - Mining in Old Ontario”, Dianne Newell, 1986
“Petroleum Mining and Oil-Field Development — a Guide to the Exploration of Petroleum Lands, and a Study of the Engineering Problems connected with the Winning of Petroleum.”, A. Beeby Thompson, 1910.
“Oil History in Ontario”, Markus Wandel - “Early development of oil technology”, Wanda Pratt and Phil Morningstar, 1987