人工太阳的能量：核聚变

With energy, people live, plants grow, machines move, and the world survives. Sounds familiar? 

有了能量，人类生存，植物生长，机器运转，世界生机勃勃。听起来很熟悉？

Yes, that is the Sun, the ultimate energy source, the holy grail of all problems.

是的，说的是太阳，能量之源，解决一切问题的关键所在。

But can we bring it closer and carry the Sun here on Earth?

但是我们能不能离它更近一步，把太阳“带”到地球上来呢？

The Sun is basically a pressure cooker. It cooks one basic element of our universe, the hydrogen. With enough heat and density, hydrogen atoms merge.

可以把太阳看成是一个高压锅。“锅”里煮着宇宙中最基本的元素——氢。给这个“锅“施加足够的热量与压力，“锅”里的氢原子就会聚合。

This is fusion, and it can create an enormous amount of energy. 

这就是核聚变。这个过程可产生巨大的能量。

Actually, it produces nearly 4 million times more energy than burning coal or gas. 

事实上，核聚变产生的能量是燃烧煤或气的400万倍

But the cooker is special. It is very hot and very packed.

但太阳这个“高压锅”很特别。它相当热，而且密度相当高。

And it is almost impossible to create such a cooker on the Earth. No Earth materials can withstand the high temperature and pressure that sustain fusion in the Sun.

而要在地球上复制这么一个“高压锅“几乎不可能。地球上没有材料能承受得了如此高的温度和密度。

The most promising prototype is called tokamak. This is EAST (Experimental Advanced Superconducting Tokamak), a tokamak built in China’s eastern city of Hefei in 2006.

最有可能实现的方式是通过一种叫托卡马克的装置。在我身旁的是EAST，是中国于2006年在合肥研制的全超导托卡马克装置。

The key is to create a system that is extremely hot, but also stably contained and monitored. 

这个装置的关键就是制造一个超高温，但是又可以被稳定控制和检测的系统。

"Tokamak is a kind of machine. This machine can generate a very strong magnetic field. When the material is heated at a very high temperature, it can become plasma. The electrons can move away from the atom and become free motion charged particles. The strong magnetic field can confine these particles. In that case, we can have a high-density, high-temperature plasma in the machine," said Xu Guosheng, Director of the Tokamak Physics Division at Institute of Plasma Physics, Hefei Institutes of Physical Science

“托卡马克是一种机器。这种机器可以产生非常强的磁场。当里面的物质达到一定温度后，会变成等离子体。电子可以从原子中分离成为自由活动的粒子。强磁场可以把这些粒子限制在里面。在这种情况下我们就可以有一个高密度高温度的环境。”中科院合肥物质科学研究院等离子体所，托卡马克物理研究室主任徐国盛在采访中介绍到。

In 2018, the EAST achieved a temperature of over 100 million degrees Celsius. That is more than six times as hot as the core of the Sun. And it sustained the temperature for 10 seconds before shutting down.

2018年，EAST实现等离子体中心电子温度1亿摄氏度，也就是太阳中心温度的六倍，并且成功维持长达10秒。

It is not a Sun on the Earth, yet it realizes wild and intense nuclear fusion. But it needs a harness to contain the energy. The Chinese came up with a key technology: magnetic field with superconducting. It lasts long and uses minimum amount of electricity. The tokamak is a success and a stepping stone toward a real fusion reactor.

准确来说，EAST还不能算是地球上的太阳。但是这个装置却能控制着核聚变原始而强烈的能量。这种能量需要被控制。于是中国发展出了一项关键的科技：磁场用超导体做成的托卡马克。超导体可以用最小的电力产生长时间的磁场，是中国设计和运行真正反应装置上的成功的一步。

The team here aims to make China’s own nuclear fusion reactor. The ambition is to solve engineering problems to produce more energy for longer time.

这次，这个团队的目标是制造中国自己的核聚变反应装置。他们的目标是解决工程上的问题，以便在更长的持续时间内生产更多的能源。

But there is a big problem: it is not worth it. 

但目前的问题是，这样做是否值得？

So far, all machines have used more power to make fusion than those produced by fusion. To make fusion a viable energy source, the devices need to become much more efficient.

目前已有的核聚变装置都无法实现输出能量大于输入。要想真正利用核聚变产生的能量，这些装置必须突破这一点才行。

ITER promises to get us there. ITER is world’s largest tokamak underway, supported by 35 countries, including the European Union, U.S., Russia, China, Japan, South Korea and India. The construction of the device is expected to be completed around the 2024 period. And it targets to go nuclear in 2035.

ITER承诺做到这一点。ITER是全世界在建的最大的托卡马克装置，将由35个国家协力完成，包括欧盟成员国、美国、俄罗斯、中国、日本、韩国和印度等。设备的装配预计在2024年完工，有望于2035年实现核聚变的目标。

“One of the two major difficulties in achieving nuclear fusion is that we have to maintain the plasma at a very high temperature for a long time. China is in a leading position globally in terms of stably operating superconducting tokamak for a long time. We have been holding the world record in this regard,” added Xu. 

“实现核聚变最主要的两大困难，一个就是聚变物质等离子体、高温等离子体要在非常长时间尺度维持它。中国在超导托卡马克长时间稳态(运行)，就是非常长时间维持聚变等离体方面。在目前国际上是最先进的，而且是我们一直保持着这方面的世界纪录。”徐国盛补充说到。

Fusion is revolutionary. But It takes money, commitment, and most important of all, vision. Even the most optimistic predict it will take decades before the technology comes to fruition. The Chinese took the challenge and want to join the world’s best minds for the endeavor. The appeal is obvious – it will serve 1.4 billion Chinese with clean and efficient energy for a millennia and give the world a real holy grail.

核聚变是革命性的。但是研发的过程需要资金，责任感，还有最重要的愿景。在最乐观的情况下，核聚变技术成熟也要等几十年。中国已经接受了这个挑战，并且集中了全世界的聪明才智朝这个方向努力。核聚变吸引力显而易见：它能让中国14亿人口用到取之不尽的清洁能源，成为全球“能量的圣杯。”

Fusion is a bold idea. It will elevate human energy use into new dimensions. But like all next generation technologies, the process is very humbling. We ran into problems, we got frustrated and we moved on. Like making nuclear bombs and landing a man on the moon-we choose to do it because it is hard, extremely hard.  

可控核聚变是个大胆的想法。它的成功将意味着人类的能源利用跨入新维度。但与所有新技术一样，实现它的过程很漫长。我们会遇到挑战，遇到挫折，然后继续前进。就像制造核弹和登月一样，实现核聚变的挑战很大，要克服的困难很多。

And everything good is hard to get. And the scientists from China and the rest of the world are working together because they believe fusion energy will be energy of the future and that future is coming. 

但要获得美好的事物，从来都不容易。中国和其他国家的科学家们通力合作，因为他们相信这项技术代表未来，而这个未来正在到来。

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