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Grand Challenge 2 How We Make Things
Grand Challenge 2 How We Make Things
How does the way we make things affect climate change? Why does cement production emit so much carbon? Discover how we can reduce CO2 emissions when we make things.
As this video progresses, key ideas will be introduced to invoke discussion.
Think about the following questions as you watch the video
What are the three primary ways greenhouse gases are produced in manufacturing?
Why can’t we just stop making stuff, or make less stuff?
What are the Solutions in the How We Make Things Grand Challenge?
What’s the simple fact about concrete production that makes this challenge so daunting?
To what extent will clean energy help reduce emissions from concrete production?
What are possible ways to produce cement that release less carbon?
Why is policy essential to support the spread of low-carbon cement?
: Humans are making a lot of stuff, and I don't just mean plastic straws and plush Pokemon toys—I mean
: big stuff. The global population is growing (I mean you probably knew that). But did you know that by
: 2060 we'll have doubled the number of buildings on Earth? Here's what that means: on a global scale,
: we're going to be building the equivalent of New York City every month for the next 40 years. That's
: 480 additional New York's! Most of that growth will be concentrated in places like China, India,
: and Nigeria, where millions of people are pulling themselves out of poverty and migrating to cities.
: That's not a problem, it's a good thing. But you know what is a big problem? Almost all the stuff
: we humans make produces some greenhouse gas. But concrete and steel produce a lot of it.
: Cement, the main ingredient in concrete, is probably the biggest offender.
: Cement production alone accounts for 8 percent of the carbon we put into the atmosphere
: each year. Building 480 new New York cities in the next 40 years is going to require
: a lot of concrete. Finding carbon-free methods to make the cement needed for all that concrete
: is going to be very important. And that effort is a big part of Grand Challenge #2: How We Make
: Things. Altogether, making things is responsible for 31 percent of greenhouse gas emissions—almost a
: third of all global emissions. That's the largest percentage of any of the Five Grand Challenges.
: How does making things generate greenhouse gases? There are three main ways: first, it
: takes a lot of electricity to make stuff. Using electrical power in and of itself isn't a problem.
: But how that power is generated matters a great deal. If electricity used to make materials comes
: from renewable sources, that's fine. But today, most of it comes from burning fossil fuels, which
: produces lots of greenhouse gas. Second, we need extreme heat to make cement and steel: for example,
: steel production requires melting iron at 3,000 degrees Fahrenheit. That produces a lot of carbon.
: Finally, the chemical reactions that turn raw ingredients into steel or glass or cement,
: also directly produce carbon dioxide.
: So if making stuff emits so much greenhouse gas, why don't we just stop making stuff?
: Sure, we can make less stuff, but even that drastic step wouldn't be enough. Remember, we're not just
: talking about consumer goods like single-use plastic bags or plastic straws. The big emitters,
: especially concrete and steel, are used for things people need; that includes buildings to live and
: work in, bridges and roads to get to places, and internet cables to connect us to each other.
: So making less stuff isn't really the solution. We also need innovations that
: let us make the big stuff without putting as much greenhouse gas into the atmosphere.
: Most of this video is going to focus on low carbon concrete. But that's just one of the pathways
: you can explore as you seek solutions to the Grand Challenge of how we make things.
: We'll also need solutions for other materials, like steel.
: Super tall resilient buildings and infrastructure are possible thanks to the combination of concrete
: and steel, and we're going to need a lot more steel. By 2050, our steel production will be emitting 2.8
: billion tons of CO2 each year. Another set of solutions is to find alternative building
: materials to replace cement and steel. For example, some companies are developing
: technologies to make a cement-like material from naturally growing substances like mushrooms.
: Our fourth innovation is all about finding something to do with the carbon that's being
: produced by the chemical reactions that happen when we make cement and steel. Maybe, for example,
: we can find ways to capture, store, and reuse all the carbon produced through manufacturing.
: But, let's get back to cement for a moment. We use a lot of cement: in the United States we
: make more than 96 million tons of cement a year. That's 600 pounds for every person.
: In the 20th century, the United States built a lot of new stuff as its population grew,
: constructing new cities and massive infrastructure projects. Concrete was
: a big part of that expansion: from 1901 to 2000, the United States made 4.3 billion tons of cement.
: That sounds like a lot, right? Well, now in the 21st century, China is undertaking its own expansion,
: building new power plants and urban infrastructure. In the 15 years from 2001 to 2016, China made 25.8
: billion tons of cement—six times more than the United States made in the entire 20th century.
: We need to find concrete solutions, but that will be hard. The challenge starts
: with a simple equation: limestone plus heat equals calcium oxide plus carbon dioxide.
: The calcium oxide in this equation is the cement we need. The carbon dioxide is a byproduct that's
: released into the atmosphere when you make that cement. If you make one ton of cement, you produce
: one ton of carbon dioxide. This simple fact is what makes this innovation pathway so daunting. Right
: now, there's not much we can do to change this chemical reaction. If we want to make cement, we're
: going to get carbon dioxide as a byproduct. So, if we're going to get to zero in how we make things,
: we'll need to make our cement production as efficient as possible. And, we'll need to
: find ways to stop the carbon produced in that chemical reaction from entering the atmosphere.
: One way to do this is to use cleaner energy. The chemical reaction that produces cement takes a lot
: of power. So, using renewables to power factories and to produce the heat needed for manufacturing
: would help. But adopting renewable energy costs more than burning fossil fuels for now.
: Cement manufacturers will need incentives to make these changes
: and we'll need to produce renewable energy at much larger scales. And that will only help a little bit.
: There are also some possible ways we could make cement that would release less carbon.
: For example, some researchers are trying to find methods to inject carbon back into the
: cement while it's being made. But they need to do more research to make this technology work,
: and to make it cheap enough for people to use. Other researchers are looking for ways to
: make cement using waste materials, like ash from coal plants, byproducts from steel manufacturing,
: or even corn husks. This might also reduce the carbon footprint of the final product.
: And of course, it's possible for governments to require cement manufacturers to capture some of
: the carbon they produce, using carbon capture and sequestration. But these
: technologies are still expensive: for cement, clean manufacturing would cost up to 140 percent more.
: And since we're manufacturing these materials on such large scales, those premiums make it
: unlikely that manufacturers will adopt low-carbon methods without government policies and subsidies.
: You might have noticed that we didn't suggest just making less cement;
: it's a nice idea, but the truth is that global populations are growing, and as countries like
: Nigeria, Vietnam, and Indonesia grow wealthier and larger, they will need to build a lot more. In other
: words, there's no single solution to the problem of concrete-related greenhouse gas emissions.
: But, maybe a million little changes can all work together.
: Now, making a million little changes is really complicated stuff,
: and you may be asking yourself, "What can I do to help?" And again, there are a lot of possible answers.
: Obviously, we desperately need more innovations that will help us produce cleaner cement
: or replace it with low carbon alternatives. Maybe you could study to become a chemical engineer,
: joining the search for alternative materials and new processes for making cement; you could
: also advocate for replacing fossil fuels with renewable energy sources and cement manufacture;
: and of course, you can lobby your local state or federal government to incentivize and fund
: innovations in making cleaner cement and mandating carbon capture. In each case, you'll have to
: consider what innovations might be most suitable to your community. Are there any large factories
: in your town? Does your town depend on tax revenue from a manufacturer? Do you live in a place that's
: expanding and will be using a lot of concrete and steel? Your activism might convince people in your
: town to support better policies that will prevent more carbon emissions from how we make things. But