Short video spoiler history: The beginning of modern warfare

Chapter 99 Hydrogen Energy

[Mankind’s several industrial revolutions were actually built on energy revolutions. For example, the first industrial revolution was based on the invention of the steam engine, and the second industrial revolution was based on the widespread use of electricity and internal combustion engines.]

[Hydrogen is one of the energy sources that humans are betting on in this energy revolution. Compared with wind and solar energy, its acquisition method is more stable, and its technology is simpler than controlled nuclear fusion.]

[Because it has a wide range of raw materials and a high combustion calorific value, which is three times that of gasoline of the same quality, and after it is burned, hydrogen and oxygen combine to form water, which does not pollute the environment. It is the most ideal energy source for mankind in the 21st century.]

[For example, the liquid fuel in the propellant of the Shenzhou 17 spacecraft uses a fuel combination of liquid oxygen and liquid hydrogen]

[There are many ways to prepare hydrogen, which can be roughly divided into hydrogen production from chemical fuels and hydrogen production from water electrolysis. Hydrogen production from chemical fuels is divided into gray hydrogen and blue hydrogen according to the degree of carbon emissions. Hydrogen production from water electrolysis is also called green hydrogen because it does not produce pollution.]

[We know that the chemical expression of water is H2O. After electrolysis of water, water molecules will decompose into hydrogen and oxygen. The chemical reaction equation is as follows: 2H20 = 2H2↑+ O2↑, provided that electricity is turned on. ]

[Prepare a sealed container such as a storage box, connect two metal rods to the bottom, then cover the metal rods with two bottles, and connect them through conduits to collect the hydrogen and oxygen produced by electrolysis. After injecting water to cover the metal rods, cover the lid of the storage box. A simple water electrolysis hydrogen production device is ready.]

[Here, the metal rod connected to the positive electrode produces oxygen after electrolyzing water, and the metal rod connected to the negative electrode of the power supply produces hydrogen. The reason for this separation is to extract as pure hydrogen as possible. In industry, direct current is generally used to electrolyze water to produce hydrogen. Because of the conversion of positive and negative electrodes, alternating current causes the gas obtained by electrolysis to be a mixture of hydrogen and oxygen.]

Ming, Jinling City.

Although we know that hydrogen energy is still a long way off, its research can be put on the agenda as a reserve technology.

Therefore, everyone in the Science Department carefully recorded the knowledge mentioned by Tianmu. There were not many pure knowledge points involved, and the principle could be summed up in one sentence.

Sun Chuanshi murmured to himself that the principles of many later studies were actually not complicated, and could even be said to be very simple. However, if the principles were not known, they would not be created for thousands of years.

The difficulty of many technologies lies not in the principles, but in the techniques and means of implementation. Everyone in the Science Department is well aware of this.

"Fortunately, we have prepared a DC generator in advance." Sun Chuanshi muttered to himself. When mentioning generators before, Tianmu had mentioned that the manufacture of DC is similar to that of AC generators, so the Ministry of Industry has them. Normally, since no difference can be seen, in order to avoid trouble, AC generators are used, and the electricity used is naturally AC.

"I remember that hot air balloon video mentioned that when a hot air balloon and a hydrogen balloon are used as a hybrid, the hydrogen balloon will explode." Zhu Biao was a little unsure. This happened a long time ago, and the information he came across later was also complicated and diverse.

"That's true." Many people recalled that the development of hot air balloons stagnated for a time because of this incident.

The clerk in charge of this part of the information quickly began to search through the pile of old papers. Because there was a catalog and it was regularly organized, it was very quick to find the information.

"That's true!" Zhu Yuanzhang circled it and passed it around among the crowd.

"I didn't expect this hydrogen to be so dangerous."

Everyone noticed that the word used was "explosion". As they are all combustible energy sources, the word "combustion" is used to describe petroleum and coal, while the word "explosion" is used to describe hydrogen balloons. It can be seen that hydrogen is a very dangerous energy source.

Zhu Yuanzhang didn't care much about it. He noticed the time point, "According to the later calculation of the year, this hydrogen balloon should be a product of the 19th century. Why is it considered the most ideal energy in the 21st century?"

As soon as I said this, I had a rough answer in my mind: the cost is high.

"Because of the high cost?" Many people also speculated, and their guess was similar to Zhu Yuanzhang's. Compared with oil that gushed out of the ground as soon as it was dug, the electrolysis of water to produce hydrogen was too difficult.

Although the principle is not complicated, how much hydrogen can be electrolyzed per kilowatt-hour of electricity?

These are still unknown.

"In addition to this, there may be other problems. Let's wait and see." Zhu Yuanzhang knew that people in later generations were definitely not fools. Hydrogen energy is so good. If it could be used on a large scale, it would have been promoted long ago. Why is it only now being called the energy of the 21st century?

Everyone nodded. They knew that aerospace was a technology that would require very high technical content in later generations. At that time, the International Space Station had to involve sixteen countries in its construction. One could imagine how difficult it was.

All of them use liquid hydrogen as fuel, which means that hydrogen is definitely the best fuel. Once a series of problems such as high cost are overcome, it will surely be quickly popularized and applied, and may then bring human society to a new level.

When I think of the enthusiasm in everyone's hearts, no one has ever said that we can't skip the first and second industrial revolutions and go directly to the fourth industrial revolution.

Just like today, if large-scale power generation and transmission had not been realized, the steam engine might have been eliminated before it was widely promoted.

[At the same time, in order to increase the conductivity of water and enhance the efficiency of electrolysis, we generally add sodium hydroxide (the product obtained by electrolyzing saturated salt water). If there is no sodium hydroxide, saturated salt water can be used instead, but after electrolysis, hydrogen H2 and chlorine Cl2 are produced.]

[Take a direct current of about 12 volts, and test it with an ammeter to see that the current is about 3A. Then power on the simple device, and you can see that dense bubbles instantly emerge on both sides. These bubbles are formed by the emergence of hydrogen and oxygen.]

[At the same time, you can see that the bubbles at the positive electrode are denser than those at the negative electrode. This is because the hydrogen obtained by electrolyzing water is twice as much as oxygen. Use a plastic bag to collect the gas from the catheter at the positive electrode, which is hydrogen. ]

[As hydrogen is very light, you can see the plastic bag rise up when you let go. Doesn't this look like a hydrogen balloon? Actually, not really. Hydrogen is dangerous, so although the balloons sold on the market are called hydrogen balloons, they are filled with helium. Hydrogen, helium, aluminum, beryllium and boron are not much different in quality, but helium is less reactive, non-combustible and safer, so helium is used instead of hydrogen.]

[Replace the conduit with a thinner metal conduit, bring an open flame close, and you can see a light blue flame coming out]

[Because our simple device above is not completely physically isolated, the collected hydrogen is not very pure. It contains a certain amount of oxygen. Large-scale industrial production of hydrogen generally adds a layer of proton exchange membrane to allow only hydrogen ions to pass through.] [If you want to make a device with a larger gas production capacity, the recommended way is to increase the electrolyte concentration or increase the current, and be sure not to increase the voltage.]

"Saturated salt water solution is written as NaCl." Zhu Biao muttered and wrote it down, "Then the saturated salt water is electrolyzed to produce hydrogen and chlorine. The solution at the bottom is sodium hydroxide."

“Will the sodium hydroxide added when electrolyzing water to produce hydrogen be consumed?”

"We need to do experiments to find out." People from the Science Department responded, but they were confused about how to calculate it and had no idea.

Zhu Biao nodded. He knew that these problems would take time to verify one by one, and self-reliance was the truth.

Hexing Tea and Snack Shop.

Manager Wan was only thinking about business. When he saw Tianmu mention the hydrogen balloon, he started to think. This would be a good toy. A balloon that would run by itself when you let go of it would be so novel.

But thinking about the risks, I decided to give up. It would be easy for the folks to tear it into pieces, and then eat with their chopsticks in one place and one place at a time.

"This is the universal periodic table!" The diners' eyes lit up. The hydrogen mentioned here is the first element in the periodic table.

The naughty kid from the Fang family, who had previously been laughed at by his father, tilted his head and recited "Hydrogen Helium Aluminum Beryllium Boron".

The naughty kid didn't understand the meaning of each word. His father asked him to remember it well, saying that he would need to learn it in the future at the academy. Only then did he figured it out a little bit when he was reciting it. It turns out that this is what hydrogen looks like.

Shopkeeper Wan looked at it with a smile. This thing is called the periodic table. The people of Jinling City think it is magical and call it the universal periodic table.

For example, the technique of turning mercury into gold was talked about by many people. Some people also collected a lot of mercury in the hope of learning how to make gold with rays in later generations. However, they were poisoned for unknown reasons and many people died. This trend was suppressed a little.
Later on, everyone watched with a smile as the naughty kid from the Fang family recited the universal periodic table. Anyway, the proton exchange membrane that came after it was just for fun. It was undoubtedly an unknown material that the imperial court could not produce, let alone an individual.

[Does hydrogen have any disadvantages? Yes, it does. The technology is immature and it is expensive! ]

[Hydrogen can now be sold for about 35 yuan per kilogram, and the cost of gray hydrogen is generally less than 25 yuan, with a gross profit margin of about 40%]

[The cost of gray hydrogen is positively correlated with the price of its raw materials, namely coal and natural gas. When the prices of coal and natural gas fall, the cost of gray hydrogen can even be as low as 7 yuan. If carbon capture technology is added to make blue hydrogen, the cost per square meter will only increase by about one yuan.]

[For hydrogen production by water electrolysis, at an electricity price of 4 yuan per kilowatt-hour, the cost of hydrogen production by alkaline water electrolysis can be reduced to 25 yuan per kilogram, which is similar to the upper limit of the cost of gray hydrogen. In Xinjiang and Gansu, my country, the electricity that has been generated but not connected to the grid is produced by water electrolysis to avoid waste.]

[Proton exchange membrane electrolysis hydrogen production, the cost is still about 33 yuan, basically no profit]

[Therefore, the market share of green hydrogen is currently less than 1%, about 80% is still gray hydrogen, and blue hydrogen barely accounts for 20%]

[If green hydrogen wants to be on par with grey hydrogen, the electricity price must drop to less than 0.2 yuan, and if it wants to have a competitive advantage, it must drop to less than 0.1 yuan]

[This in turn requires the development of new energy technologies such as photovoltaics and wind power. Therefore, although hydrogen fuel cell vehicles have many advantages such as long driving range, fast energy replenishment, and low temperature resistance, they cannot be vigorously developed because the cost of green hydrogen is too high.]

[In addition, because hydrogen molecules are too small, the storage and transportation of hydrogen will be very troublesome. Currently, it is proposed to convert hydrogen into liquid fuels such as methane for transmission.]

Tang Dynasty, Chang'an City.

Li Shimin listened to the entire video carefully and gained a general understanding of the entire hydrogen production process, as well as a certain understanding of the difficulty of energy reform.

It can be said that there are still many difficulties, such as cost, storage and transportation, safety, etc., but it is also a very excellent fuel.

"Any energy revolution cannot be achieved overnight." Li Shimin thought of electricity. From its discovery to its popularization, it must have involved the hard work of countless workers and researchers, but Tianmu did not mention it so he did not realize it.

"Record it first!" Li Shimin knew that he did not have the strength to research the new generation of energy. The most important thing at present was to lay railways, power lines, etc., and popularize coal mines, oil, electricity, etc.

With these infrastructures, subsequent application development will be a natural thing.

This step may take hundreds of years.

"Not only is hydrogen difficult to store and transport, it is also difficult to use. I have never seen a hydrogen gas stove. It is too unsafe. It is better to convert it into methane with carbon dioxide."

"Under current circumstances, it is acceptable to use hydrogen directly as a fuel in industry, but this is unlikely in real life. It is more likely to be converted into large molecular hydrogen compound fuels before use for safety, storage and transportation purposes."

Ming, Jinling City.

A group of clerks recorded some of the discussions in the comment section, but sometimes they still couldn't keep up with the pace.

(End of this chapter)