MMass production of many manmade materials would make it impossible to create orn societies. Affluent societies could provide plenty of food and comforts. They also have access to health care and education. We would not be able to enjoy the many benefits of the inventions we have made.
The four most essential materials are cement, steel and plastics. They are more important than other inputs. Globally, there are approximately 4.5 million tonnes of cement annually. Nearly 400 million tonnes of steel is produced each year. 180 million tons per year of ammonia are also produced. But it is ammonia that deserves the top position as our most important material: its synthesis is the basis of all nitrogen fertilizers, and without their applications it would be impossible to feed, at current levels, nearly half of today’s nearly 8 billion people.
The dependence is even higher in the world’s most populous country: feeding three out of five Chinese depends on the synthesis of this compound. This dependence easily justifies calling ammonia synthesis the most momentous technical advance in history: other inventions provide our comforts, convenience or wealth or prolong our lives—but without the synthesis of ammonia, we could not ensure the very survival of billions of people alive today and yet to be born.
Plastics are a large group of synthetic organic materials whose common quality is that they can be molded into desired shapes—and they are now everywhere. While I write, my Dell laptop keys and the wireless mouse beneath my right hand are made of acrylonitrile-butadiene styrene. As I type, I’m sitting in a swivel chair that is upholstered in polyester fabric. The nylon wheels of the chair rest on a protection mat of polycarbonate which covers a polyester carpet. Plastics have become indispensable for hospitals and health care generally. The plastics that surround life now include maternity wards as well as intensive care units are indispensable. These items include flexible tubes for feeding and delivering oxygen and other medical equipment.
Steel’s strength, durability, and versatility determines the look of modern civilization and enables its most fundamental functions. This metal is widely used and forms numerous visible and invisible critical components for modern civilization. Moreover, nearly all other metallic and non-metallic products we use have been extracted, processed, shaped, finished, and distributed with tools and machines made of steel, and no mode of today’s mass transportation could function without steel. A car averages around 900 kg of steel. Before Covid-19, the world produced nearly 100 million cars a year.
Concrete’s key ingredient is cement. It can be combined with water, sand and gravel to make the most widely used material. Concrete is everywhere in modern cities, including bridges, tunnels roads dams runways and airports. China now produces more than half of the world’s cement and in recent years it makes in just two years as much of it as did the United States during the entire 20th century. A further astonishing statistic is that the world consumes one-year more cement per year than during the whole of the first half 20th century.
Although these materials have very different properties and characteristics, they all share the following three traits. They are difficult to replace (certainly not in a short time or on a worldwide scale), and we will require more of them. Their mass-production is heavily dependent on the burning of fossil fuels. This makes them major contributors of greenhouse gas emissions. The low amount of nitrogen in organic fertilizers and the large mass they have worldwide cannot replace synthetic ammonia. Even if every crop residue and manure was recycled, this is not sufficient. There are few other materials that offer so many light-weight, yet long-lasting uses like plastics. Steel is the strongest metal. Concrete (often reinforced by steel) is the best mass-produced metal for building infrastructure.
The future requirements could be met by high-income countries (eating less meat and wasting less), while China and India could decrease their excess fertilizer application. However, Africa, which has the fastest growing population, is still deprived of fertilizers, even though it is a significant food importer. Any hope for its greater food self-sufficiency rests on the increased use of nitrogen: after all, the continent’s recent usage of ammonia has been less than a third of the European mean. For medical purposes (aging population), infrastructural (pipes), and transportation, more plastics are needed (see interiors of high-speed trains and airplanes). Like ammonia in the United States, steel demand must rise in low-income countries that have poor infrastructures. More cement is required to produce concrete. Affluent countries will need to repair decaying infrastructures. In the US, every sector where concrete dominates, such as roads, dams, and aviation, receive a D grade. Low-income countries can expand their cities, sewers, and transport systems.
The transition to renewable energy will require huge quantities of concrete, steel and plastics. No structures are more obvious symbols of “green” electricity generation than large wind turbines—but their foundations are reinforced concrete, their towers, nacelles, and rotors are steel, and their massive blades are energy-intensive—and difficult to recycle—plastic resins, and all of these giant parts must be brought to the installation sites by outsized trucks (or ships) and erected by large steel cranes, and turbine gearboxes must be repeatedly lubricated with oil. If all these components were manufactured without fossil fuels, the turbines could generate true green electricity.
All of these materials are produced using fossil fuels.
Natural gas is used in ammonia synthesis as both the hydrogen source and the energy source to produce high pressure and temperature. Most plastics contain simple molecules made of natural gas or crude oil. Some 85 percent of the world’s total production is based on these basic molecules. Additionally, hydrocarbons can provide energy for the syntheses. Primary steel production begins with the blast furnace smelting the iron ore. Coke is made from coal, with natural gas added. The resulting cast iron can then be made into steel using large basic oxygen furnaces. Cement is made by heating limestone, clay and shale in large, inclined metal cylinders and using low-quality fossil fuels like coal dust and petroleum coke.
As a result, global production of these four indispensable materials claims about 17 percent of the world’s annual total energy supply, and it generates about 25 percent of all CO2 emissions originating in the combustion of fossil fuels. This dependence is so widespread and large that it makes decarbonizing the four main pillars modern civilisation extremely challenging. Replacing fossil fuels in their production will make electricity generation more expensive and difficult than renewables (mainly, wind and solar). Eventually, new processes will take over— but currently there are no alternatives that could be deployed immediately to displace large shares of existing global capacities: their development will take time.
The hydrogen could also be used to synthesize ammonia, and for smelting iron. We know how to do that—but it will take some time before we could produce hundreds of million tons of green hydrogen derived from the electrolysis of water by using wind or solar electricity (virtually all of today’s hydrogen is derived from natural gas and coal). The best forecast is that green hydrogen would supply 2% of the world’s energy consumption by 2030, far below the hundreds of million tons that will eventually be needed to decarbonize ammonia and steel production. Decarbonization of cement production cannot be accomplished by using only waste materials or biomass. Therefore, new methods must be created and commercialized in order to reduce cement’s CO2 emissions. It is also not possible to completely decarbonize the plastic industry. There are many options available, from plant feedstocks, more recycling, to substituting other materials, to carbonize it.
And beyond these four material pillars new and highly energy-intensive material dependencies are emerging and electric cars are their best example A typical lithium car battery weighing about 450 kilograms contains about 11 kilograms of lithium, nearly 14 kilograms of cobalt, 27 kilograms of nickel, more than 40 kilograms of copper, and 50 kilograms of graphite—as well as about 181 kilograms of steel, aluminum, and plastics. These materials are required to process approximately 40 tons of ore. Due to the low content of elements in many ores it requires extracting and processing around 225 tons. This would mean that road transport electrification will be required to increase the number of vehicles by millions every year.
Massive material flows will be a constant part of modern economies, including ammonia-based fertilizers that feed the growing global population, plastics, steel and cement required for making new machines and structures; and new inputs to make solar cells, wind turbines and electric cars. Modern civilization will continue to be dependent upon the fossil fuels that were used for the extraction and processing of these essential materials until renewable energy is available. No artificial intelligence designs, no apps, no claims of coming “dematerialization” will change that.
The following is an adaptation of HOW THE WORLD REALLY MAKES by Vaclav. Published by Viking, an imprint under Penguin Publishing Group, LLC. Copyright © 2022 by Vaclav Smil.
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