Black technology starts from the steel suit

Chapter 173 Chapter 173
But the team has not abandoned research on these materials.In an unrelated study, Skinner observed a strange effect in semiconductors exposed to strong magnetic fields.The trajectory of electrons is bent under the influence of a magnetic field.Skinner and Liang Fu thought: What kind of influence does the magnetic field have on topological semimetals?
They checked the literature and found that in 2013, a research team at Princeton University measured its thermoelectric properties under a magnetic field in order to fully characterize a topological material called lead-tin-tin-selenide.The researchers report that, in their many observations of the material, the material's thermoelectric generation increased at a high magnetic field of 35 tesla (for comparison, most MRI machines operate at about 2 to 3 tesla ).

Skinner and Liang Fu used the material properties studied by Princeton to theoretically simulate the thermoelectric properties of materials under certain temperature and magnetic field conditions.

Skinner said: "We ultimately discovered that an interesting thing happens to materials under a strong magnetic field: it can cause electrons and holes to move in opposite directions. The electrons can move to the cold side and the holes can move to the hot side. The material Both phenomena are present at the same time. As long as the magnetic field is stronger, you can in principle get larger and larger voltages from the same material."

Guided by the team's theoretical model, they calculated the ZT value of lead-tin-selenide, a value that characterizes how close the material is to the theoretical limit for generating electricity from heat.The most efficient materials reported so far have a ZT value of about 2.Skinner and Liang Fu found that under a strong magnetic field of about 30 Tesla, the ZT value of lead tin selenide can be about 5 times higher than that of the most efficient thermoelectric materials, reaching 10.

Lead tin selenide, heated to about 30k, or 500 degrees Fahrenheit, in a 440 Tesla magnetic field, has a ZT value of 10 and should be able to convert 18% of the thermal energy into electricity; Can convert 2% of heat energy into electricity.

That is to say, as long as the magnetic field is strong enough, they can control negatively charged electrons and positively charged particles to move in different directions. Does this sound dry?
The 30t ultra-strong magnetic field is absolutely beyond the reach of ordinary equipment.It even requires superconducting materials, otherwise, the heat generation will be soaring to the sky, and only a few laboratories in this world can achieve it.

So although there is a lot of noise, in fact, this material is still very far away from the actual application, at least before it has practical application significance, there is still a very, very long way to go.

Even though they recently received theoretical inspiration from Wang Feng himself and reduced the magnetic field strength to 22t, the results still remained unchanged.

At present, the sbk topological material in the Beijing Lithium Battery Research Institute has reached the temperature of 600K, the zt value has reached the level of 12, the thermoelectric conversion rate has reached 21%, and there is no special requirement for the magnetic field.

What does this mean?

It means that cars, trains, ships, etc. have a lot of waste heat, and part of their waste heat can be used again. According to conservative estimates, the current number of cars in the world has reached 75000 million, so many cars The amount of calories wasted every day is an astronomical figure.

We can recover part of the heat energy, which will undoubtedly make an outstanding contribution to improving energy efficiency and reducing carbon dioxide emissions.Of course, the most important thing is that the economic benefits have been greatly improved, and the whole world will benefit from this.

Of course, it’s not just cars, it refers to all means of transportation in general. Their fuel efficiency will become higher, and their demand for electricity will be easier to meet. They will no longer consider using too many electrical appliances. will reduce its power.Because if the electrical appliances can't be consumed, they can even consider installing several electric motors to provide more kinetic energy.

Of course, the amount of heat consumed by traffic, travel and transportation around the world is not a large amount. After all, compared with the power plants and factories around the world, this amount of heat consumption and waste is not worth mentioning at all.

From the perspective of power plants alone, our current energy utilization method or power generation method is still boiling water. Some people say that our history, or modern history, is a history of boiling water in different ways.

With the continuous development of our technology, the way we boil water is becoming more and more advanced, and there are more and more tricks to boil water, and the efficiency of energy utilization is constantly improving.

But even after more than 100 years of development, our energy efficiency is still stuck at the level of 40%, which has been unable to break through for a long time.Even the most advanced ultra-supercritical steam turbine unit has a thermal efficiency of only 45.2%, and a large amount of thermal energy is still wasted.

At a temperature of 600 Kelvin, which means more than 300 degrees Celsius, the steam temperature of the power plant can fully meet this requirement. Under ideal conditions, it can even increase our thermal efficiency by another ten percentage points. You can imagine what this is. What a breakthrough!
After all, we have achieved a breakthrough from supercritical units to ultra-supercritical units, and our thermal efficiency is only 1.2 to 4 percentage points higher. From here we can see how terrifying this breakthrough is.

Last year, I generated 7.5 trillion kwh of electricity, and the world’s total electricity generation is estimated to have reached 27 trillion kwh. Can you imagine how it would feel if the world’s electricity generation increased by 1/4? (Here, we assume that the thermal efficiency of generator sets in the world reaches 40%, which is definitely not the case. It should be slightly more than 30%.)
Considering such a major breakthrough, Wang Feng, of course, did not dare to slack off and directly reported the news overnight.He didn't need to worry about the rest. After all, their security had been further enhanced, so there was no need to consider this issue.

But what he didn't know was that the news from him blew out Director Lu who had already fallen asleep. After hearing the news, the elderly man couldn't fall asleep immediately, and drove over by car overnight .

Older people already have shallow sleep, coupled with high work pressure, especially the problem of energy allocation during the recent period, which has become a constant problem, the quality of their sleep has become worse and worse.

July and August are the peak periods of electricity consumption, and the load on the power grid is very heavy. In addition, the temperature during this period is extremely high, and the weather is hot and stuffy. If the electricity consumption cannot be guaranteed, one can imagine how the people of the whole country will greet him family.

But the problem is that he is not a magician, and he can't conjure thermal coal out of thin air. Coupled with the skyrocketing price of thermal coal around the world, power plants are even more reluctant to start up.

He originally didn't have much hope in this aspect. After all, scientific research is not farming, so it can't be harvested in two or three months.But he didn't expect Professor Wang to give him a big surprise!

"It's raining in time, Professor Wang is really raining in time, it's worth my effort to help him run up and down!" Director Lu got into the car excitedly, full of energy, he didn't look like he just stayed up late at all.

(End of this chapter)