The Problem with Steel
Learn more at www.oerproject.comThe Problem With SteelBy Molly Sinnott, research by Graham GerrityExplore the promising innovations, obstacles we must overcome, and ways you can help make a difference to reduce emissions from the way we manufacture steel.
2The Problem With SteelBy Molly Sinnott, research by Graham GerrityThe state of steel todayEvery comic book fan has their own opinion about the greatest superhero of all time. But when we compare superpowers like strength, speed, and might, it’s easy to see how Superman gets to the top of many lists. After all, who could mess with the Man of Steel? To be clear, this is an article about steel, not superheroes. But don’t be disappointed: Steel itself is pretty amazing. It does everything from supporting the largest infrastructure projects ever built to making everyday consumer items like phones and laptops. People have used steel for more than 4,000 years to make things like buildings, machines, weapons, and vehicles. It’s stuck around for such a long time because it’s both strong and easy to shape while hot. Plus, the materials used to make steel are cheap and readily available.Because steel is strong, affordable, and durable, it’s an ideal building material. So we use a lot of it—about 1.9 billion tons annually. But producing all that steel has a cost: For every 1 ton of steel produced, about 2 tons of carbon dioxide are released. This means steel production alone is responsible for nearly 8% of annual greenhouse gas emission (almost the same as cement!).Steel is made of iron and carbon. Iron is a common element in the earth’s crust. It’s usually found in a mix of oxygen and other minerals called iron ore. To make steel, we need to separate the iron from the iron ore and then add a little bit of carbon. Traditionally, we do this by using coal to melt iron ore at super-hot temperatures. In burning furnaces, iron in the iron ore binds with a small amount of carbon in coal to form steel. The leftover carbon binds with oxygen in the kiln to create—you guessed it—carbon dioxide. Inside a steel factory, a worker prepares to pour molten steel. © Getty Images.
3The Problem With SteelBy Molly Sinnott, research by Graham GerrityWhy do we make steel this way? Largely because that’s how we’ve always done it. Until recent decades, there’s been no incentive to develop new methods because the current process is cheap and easy. But as the world continues to develop, demand for steel is increasing rapidly. And unless we find a better way to produce it, emissions will increase as well. Greening steelSo how can we continue to make steel, a material that quite literally supports much of human activity, without contributing to rising global temperatures? Let’s explore a few ways that scientists, innovators, and policymakers are working together to achieve net-zero emissions from steel production. The first promising pathway for reducing emissions is to optimize the efficiency of steel production. Current methods for making steel are very energy-intensive. In fact, steel production is responsible for 8% of total global energy demand. Much of that energy is consumed by the furnaces that require super-hot temperatures to get the iron and carbon to combine. Globally, most furnaces rely on coal to reach those extreme temperatures and provide the carbon needed to bind with iron. Increasingly, however, manufacturers are using natural gas to generate energy. This shift is a step in the right direction—natural gas produces less than half the emissions of coal. What’s more, natural gas furnaces use electricity for part of the steel production process, avoiding fossil fuels altogether. Some plants like this one use recycled scrap metal to create new steel in a process that is less energy-intensive than traditional steelmaking. © Getty Images.Scientists and engineers are also pursuing innovative technologies to make zero-carbon steel. Some companies are developing methods that avoid the emissions from combining iron ore and carbon. One technique uses a process called electrolysis, in which an electrical current separates chemical compounds into their component elements. When this technique is applied to iron ore, the primary raw material in steel, this process yields the pure liquid iron you need for steel. Oxygen—not carbon dioxide—is the byproduct.
4The Problem With SteelBy Molly Sinnott, research by Graham GerrityStill other manufacturers are piloting the use of carbon capture and sequestration(CCS). Carbon capture is the process of absorbing the unavoidable emissions from production before they enter they atmosphere. Once the carbon has been captured, it can be put through a process called sequestration,which is a way of safely storing the carbon. CCS can also help reduce the impact of high-emissions factories as we work to transition to more efficient processes.Another promising innovation uses hydrogen as a fuel source during production. In this case, scientists again apply electrolysis, but now it splits a water molecule into its component elements: hydrogen and oxygen. We can then burn pure hydrogen as a zero-carbon energy source, replacing both coal and natural gas.In addition to changing the way steel is produced, we can also better use the steel we already have. Steel can be recycled over and over again. In fact, it’s the most recycled material in the world. The reason is that making new steel products from old steel scrap is significantly more cost- and energy-efficient than making new steel from iron ore. Manufacturers and builders can also use less steel or other materials entirely whenever possible. Extending the lifespan of buildings, designing infrastructure and vehicles more efficiently, and using alternative materials like timber can also all help reduce demand for steel. Obstacles and costsWe can reduce emissions from steel production. A future with green steel is within reach. But to get there, we have some big obstacles to overcome. These steel plates were created using an innovative process that relies on renewable electricity to make carbon-free iron at low temperatures. © Getty Images.
5The Problem With SteelBy Molly Sinnott, research by Graham GerrityTo start, we’ll need to convince steel manufacturers to replace inefficient and coal-powered machinery with less harmful options. Furnaces are expensive, however, and last up to 40 years. Most manufacturers aren’t willing to replace functioning equipment with new, more-efficient models. Plus, while natural-gas furnaces are lower emitters than coal-powered ones, they still burn fossil fuels, meaning they’re still emitting a significant amount of carbon. And natural gas, while readily available in some parts of the world, is not as available in other regions. It may seem like steel recycling is a no-brainer when it comes to producing cheap and efficient steel. It is, and most of the world has already caught on to the idea. About 85% of steel gets recycled, compared to about 50% of glass and just 20% of plastic. So while there’s definitely room for improvement, there’s just not enough scrap steel available to meet the increasing demand. Innovative technologies like electrolysis, carbon capture, and hydrogen fuel will likely need to be a part of a zero-emissions steel industry. But these technologies aren’t quite ready to shoulder the burden of clean steel production. They still carry a hefty green premium and need more development before they can be widely implemented. Action opportunities and careersSteel is an amazing building material, but it’s got big problems. How can you help scientists and innovators reduce those impacts?To start, we need to get governments to adopt policies in support of the solutions that already exist. For example, government policies can subsidize the purchase of new, more efficient equipment and mandate efficiency standards at factories. Other policies could offer tax credits or subsidies for companies and businesses that choose to purchase low-carbon steel. Or cities and states could encourage companies to move toward more efficient practices by putting a tax on emissions. Policies like these all work to provide an economic signal that a transition to low-emission strategies is necessary. You might also want to get involved directly and pursue a career to help expand the impact of innovation technologies. Scientists like chemical engineers are making huge advances in electrolysis technology. Might you chose to help them? Or you may want to become a process engineer and help build and maintain efficient steel plants. We’ll also need architects and construction workers to design and build projects using clean steel. Carbon-free steel would make a huge impact in reducing emissions from the way we make things. How can you help build this future?
6The Problem With SteelBy Molly Sinnott, research by Graham GerrityMolly Sinnott and Graham GerrityMolly Sinnott is a member of the Climate Project editorial team. She was previously a classroom reading and writing teacher, specializing in supporting students in executive-function skills development. She focuses on building approachable and inclusive content for a diverse range of students. Graham Gerrity is a member of the Climate Project content team. He is a graduate of Occidental College where he studied cognitive science and was previously an emergency medical technician. He focuses on finding accessible and engaging ways to communicate technical information.Credit: “The Problem With Steel”, By Molly Sinnott, research by Graham Gerrity / OER Project, https://www.oerproject.com/Image credits This work is licensed under CC BY 4.0 except for the following: Cover image: Low angle color image depicting a construction site in London, UK. A housing development is in the process of being created, and multiple cranes are hoisting materials into place. Beyond the cranes and construction equipment is a dazzling sky and cloudscape. Lots of room for copy space. © coldsnowstorm / E+ / Getty Images.Inside a steel factory, a worker prepares to pour molten steel. © Monty Rakusen / DigitalVision / Getty Images.Some plants like this one use recycled scrap metal to create new steel in a process that is less energy-intensive than traditional steelmaking. © Monty Rakusen / DigitalVision / Getty Images.These steel plates were created using an innovative process that relies on renewable electricity to make carbon-free iron at low temperatures. © Bloomberg / Getty Images.OER Project aims to empower teachers by offering free and fully supported history courses for middle- and high-school students. Your account is the key to accessing our standards-aligned courses that are designed with built-in supports like leveled readings, audio recordings of texts, video transcripts, and more. Offerings include a variety of materials, from full-year, standards-based courses to shorter course extensions, all of which build upon foundational historical thinking skills in preparation for AP, college, and beyond. To learn more about The OER Project, visit www.oerproject.com