In the third chapter of Climate Economy and the Future of Humanity, Bill Gates says that in the era of carbon neutrality, we need to find solutions for five greenhouse gas-producing activities: electricity production and storage, production and manufacturing, cultivation and farming, transportation, heating and cooling.
In chapter 4, we discuss the greenhouse gas-related issues involved in the production and storage of electricity and explore possible solutions. And Bill also stressed that we can't just wait for some future technology to save us, we have to act to save humanity itself.
Chapter Five, which is an important aspect that we are going to explore today: production and manufacturing.
Because production and manufacturing are actually not particularly easy to distinguish from many specific use links. So here is a specific division, all emissions generated by the production and manufacturing sectors are counted in production and manufacturing, and emissions generated in the process of use are counted in their respective categories.
For example, the extraction, production and refining of gasoline is included in production and manufacturing, while cars on the road, airplanes in the sky, ships in the water, and their burning of gasoline are counted in transportation. Similarly, emissions from manufacturing steel and engines are counted as "production and manufacturing", and the process of engine combustion (fuel) is counted as "transportation".
In production and manufacturing, to achieve the purpose of carbon neutrality, it is also necessary to innovate, innovate production materials and production processes, as can be seen from here, this chapter summarizes (to achieve) zero carbon manufacturing four paths.
Bill begins with the use of concrete in the world and describes the contribution of this great invention to our modern life, the skeleton of our city, which requires a lot of cement production every year to meet our urban development. At the same time, steel and concrete also constitute a perfect pair, that is, we call reinforced concrete, which can not only bear great weight, but also is not easy to twist and break.
In addition to steel and concrete, there is also plastic, which is a material that penetrates more deeply into all aspects of our lives, and as we mentioned earlier, our world cannot leave plastic at all.
There's also glass, our windows, all kinds of bottles and cans, car windshields, and light guide fibers, and so on. It's hard to imagine that without glass, we wouldn't have the cars, trains, planes, and computer screens we have now. The optical fibers just mentioned, that is, because of their existence, provide us with a high-speed Internet connection.
So now, steel, cement, plastic, glass, these are not the products of nature, they are completely human materials, these materials are the symbol of our modern civilization, there is no sign that we will abandon these materials. Whether there will be updated material in the future is unknown to us. Some materials we predict may disappear or be used less, but they don't.
For example, paper, which is considered to be the early invention and manufacture of human beings, we originally thought that with the growth of digital technology, the use of paper will decrease, but do you think that the amount of paper used now is less than before? Therefore, as the world's population grows and people's living standards improve, the consumption of various materials may increase.
Bill then gives the example of Shanghai's urban development. Compare photos of Shanghai in 1987 to 2013.
I think this example is a bit extreme, because in today's society, China's speed and Shanghai's speed are the ceiling of development, and other countries are not particularly likely to be able to catch up with this speed. So he added himself: Although the development in most places is not as remarkable as in Shanghai.
Behind the development, of course, is the mass production of steel, cement, plastics, glass, and of course, greenhouse gas emissions. So far, we haven't found a practical way to make these materials "zero carbon" produced.
Go back in history, the use of steel, dating back to about four thousand years ago. Of course, the production process at that time could only produce iron, and for thousands of years, our production process has been continuously improved, resulting in a variety of cheap and varied steel products that we can use now. We know that steel is very hard and can be molded at high temperatures. But in fact, pure iron is not particularly hard, only the right amount of carbon is added, and the carbon atom will be squeezed between the iron atoms, so that steel has its most important properties.
On Earth, the abundance of both elements, carbon and iron, is very high and not difficult to obtain. Carbon, we needless to say, the greenhouse gas we are talking about now is the compound of carbon, iron, is the most metallic element on the earth's crust, it should be said that it is one of the most metallic elements, because the most is actually aluminum.
We see that there is no shortage of these two elements on the earth, so we don't have to worry about whether this material is not enough. However, although the abundance of iron in the earth's crust is very high, pure iron is almost impossible, and in the earth's highly oxidized star, iron is generally oxidized by other elements, and finally a mixture of iron ore is formed. Then, if we want to produce steel now, we have to separate the oxygen element from the iron and add carbon to the trend, which is the process of steelmaking. With the support of modern blast furnaces, these two points are not difficult to achieve, using a kind of coal called "coke" for combustion, at high temperatures, iron ore releases oxygen, combined with coke, forming carbon dioxide, coke itself burns, will also release carbon dioxide. Of course, in this process, coke will have a small amount of carbon combined with iron to form the steel we want.
The whole reaction process is not complicated and easy to count. It has now been calculated that producing 1 ton of steel produces about 1.8 tons of carbon dioxide.
As you can see, the traditional steelmaking process is very simple and inexpensive, but the amount of carbon dioxide produced is too large.
We expect that by 2050, the world will demand about 2.8 billion tons of crude steel per year. If this smelting method is still the same, then the process of steelmaking alone will release 5 billion tons of carbon dioxide per year. You can compare this with the current global greenhouse emissions of 51 billion tons.
Next, let's look at cement. As I said, cement is an important material for making concrete.
We know that the main chemical components of cement are calcium oxide, alumina, silicon oxide, iron oxide and other oxides. Among them, calcium oxide accounts for about two-thirds, silicon oxide accounts for about one-fifth, and alumina and iron oxide are less than ten percent. So where does calcium oxide come from? Of course, it is calcium carbonate, which is obtained in limestone. When limestone is heated to 1,000 degrees Celsius, it breaks down into quicklime and carbon dioxide, a chemical equation I'm sure you'll write.
As you can see here, the first thing to heat to 1000 degrees Celsius requires the consumption of a lot of fossil fuels, there are carbon dioxide emissions, and limestone in the decomposition process, will also produce a lot of carbon dioxide.
Producing one ton of cement produces about 900 kg to one ton of carbon dioxide.
Of course, there is a preparation scheme called "ecological cement" or "green cement", that is, the raw material is mixed with magnesium oxide, so that it can be produced at a low temperature of 750 degrees Celsius, and the fuel consumption is relatively low. And there is also an advantage, saying that this cement will absorb the surrounding carbon dioxide in the process of carbonization hardening, that is, absorbing some of the carbon dioxide previously emitted.
The absorption of cement in this carbonization process should be regarded as a good thing, including of course the IPCC, which does not seem to consider this issue in its national greenhouse gas inventory. In the future, if you want to carry out more detailed statistics, I think this should not be ignored.
Let's talk about plastics, the main component of plastics is synthetic resin, rubber that can be traced back to thousands of years ago, and various substances secreted by animals and plants, such as rosin, shellac, etc. But it wasn't until the 1950s that synthetic plastics began to make their way into our lives, and there are about three hundred kinds of plastics in production in the world so far.
Whatever plastic it is, they all have one thing in common, carbon. Most of the raw materials used to make plastics are also derived from oil.
But plastics have an important difference compared to cement and steel. Carbon dioxide is released as an unavoidable by-product when producing cement or steel, and about 50 percent of the carbon remains in plastic when plastic is produced.
The oil that makes plastics is not released into the atmosphere as quickly as it is burned, on the contrary, the carbon made into plastic is difficult to release
But this leads to another major environmental problem, as plastics remain in place for a century or more after they are landfilled or enter the ocean. It's also a real problem to be solved: Plastics floating in the ocean can cause all sorts of problems, such as poisoning marine life. However, plastic does not cause the climate to deteriorate. In terms of emissions alone, the carbon in plastics is not particularly bad news. Because plastic takes a long time to degrade, the carbon atoms inside it don't leak into the atmosphere and don't cause temperatures to rise — at least not for a long period of time.
Next, Bill Gates is going to give us an estimate of the green premium. After all, only when the green premium comes down will people have the willingness to take a "zero carbon" approach. The manufacture of a product leads to greenhouse gas emissions in three aspects: (1) the production of electricity required in manufacturing; (2) the heating of fossil fuels for the manufacturing process, such as the melting of iron ore in steel production, and the high temperature in cement production; (3) the release of raw materials themselves, such as cement production, and the decomposition of limestone inevitably produces carbon dioxide.
Break down from these aspects to see how they raise the green premium.
With regard to electricity production, most of the key challenges we have already mentioned in Chapter IV will not be repeated here.
In the second aspect, many production processes require ultra-high temperatures, such as one thousand or even several thousand. Judging from the current level of technology, it is not economical to let electricity produce such a high temperature. The current approach is either to use nuclear energy or to burn fossil fuels. To burn fossil fuels at zero carbon, carbon capture devices must be installed, but carbon capture devices and operations are certainly not free, which in turn increases the cost of manufacturing.
The third aspect is how to deal with production that in itself causes greenhouse gas emissions. Similarly, to achieve zero-carbon production, fossil fuels and carbon capture devices must be used, which also increase costs.
Understanding these three aspects makes it possible to estimate the green premium range for plastic, steel and cement production.
From this table, we can see that the green premium for plastics and steel is not very high. For the lives of ordinary people, it is true that the pressure of price increases may not be felt. Up one or twenty percent, isn't that a small case? But engineering is different, if you want to repair a bridge now, which includes cement and steel, and even plastic, the price difference is very large. If you're a builder, you probably care a lot about the double cost. If there are no other incentives or legal requirements, no one will choose at all. Specific incentives, Bill said, will be covered in Chapters 10 and 11. When we get to that point, when we read this, we'll read it again, and here's just a brief mention.
So, can we achieve "zero carbon" manufacturing through innovative production processes? Of the materials we are talking about today, the challenge of making cement is the greatest. This simple fact is difficult to get around: limestone is heated, pyrolyzed into calcium oxide and carbon dioxide, which is a chemical reaction that cannot be deciphered. For the foreseeable future, we may all have to rely on carbon capture devices to capture the carbon dioxide produced during cement production.
The change in the steelmaking process mentioned by Bill is very much worth looking forward to, that is, replacing coal with electricity.
This process is called "molten oxide electrolysis": instead of using coke and furnaces to smelt iron, electricity is passed through an electrolytic cell containing liquid iron oxide and other components, from which iron oxides can be separated by electricity, resulting in pure iron used to produce steel and pure oxygen as a by-product. During the whole process, no carbon dioxide is produced. This is a promising technology, similar to the aluminum purification process we have been using for more than a century. However, as with other ideas for the production of clean steel, whether the technology can achieve industrial-grade applications has yet to be further confirmed.
Plastic production, in fact, is also very promising, and even if we combine enough steps, plastic production may become a "carbon sink", because the composition of plastic contains carbon, but it is not easy to decompose, so the production of plastic is carbon consumption, not carbon emissions. Do you think this is the truth?
Bill concludes by summarizing the path to zero emissions in the manufacturing sector as follows:
1. Electrification of all processes as much as possible, which requires a lot of innovation;
2. Get the electricity you need from the grid that has been "decarbonized", which also requires a lot of innovation;
3. The use of carbon capture devices to absorb the remaining emissions, which also requires a lot of innovation;
4. The more efficient use of materials is also inseparable from a lot of innovation.
Well, this chapter is relatively simple, and we take the production of steel, cement, and plastics as an example to illustrate the pressure on carbon emissions in the production and manufacturing process, and the possibility of achieving carbon neutrality in the production process.