How does nuclear plant work

Have you ever been in an argument about nuclear power? We have, and we found it frustrating and confusing, so let’s try and get to grips with this topic.

你有没有对核能问题进行过研究呢？我们有过，而且我们发现这个话题又难又无聊所以就让我们简单了解一下这个话题。

It all started in the 1940s. After the shock and horror of the war and the use of the atomic bomb, nuclear energy promised to be a peaceful spin-off of the new technology, helping the world get back on its feet. Everyone’s imagination was running wild. Would electricity become free? Could nuclear power help settle the Antarctic? Would there be nuclear-powered cars, planes, or houses? It seemed that this was just a few years of hard work away. One thing was certain: the future was atomic.

这一切始于上世纪四十年代。在战争和核弹带来的震惊和恐惧过去之后，核能成为了一个美好的意外收获，它能帮助世界恢复过来。每个人的想象力都像脱缰的野马。以后电会不要钱吗？核能会不会让定居南极成为可能？会不会有核能驱动的汽车、飞机以及房屋？似乎在短短几年的努力之后，这些都将成为可能毫无疑问的是，未来属于核能。

Just a few years later, there was a sort of atomic age hangover; as it turned out, nuclear power was very complicated and very expensive. Turning physics into engineering was easy on paper, but hard in real life. Also, private companies thought that nuclear power was much too risky as an investment; most of them would much rather stick with gas, coal, and oil. But there were many people who didn’t just want to abandon the promise of the atomic age; an exciting new technology, the prospect of enormously cheap electricity, the prospect of being independent of oil and gas imports, and, in some cases, a secret desire to possess atomic weapons provided a strong motivation to keep going.

但短短几年后，核能发展面临了瓶颈人们发现，核能实际上非常复杂且昂贵将理论转化为现实，说起来容易做起来难同时，私人企业普遍认为核能作为投资风险太大，他们大多更喜欢石油、天然气和煤炭。但是仍有很多人不愿意就这么放弃核能这项激动人心的新科技和美好未来大量廉价的电力，不再依赖石头天然气进口，以及偷偷研究核武器的想法，都给核能研究提供了动力。

Nuclear power’s finest hour finally came in the early 1970s, when war in the Middle East caused oil prices to skyrocket worldwide. Now, commercial interest and investment picked up at a dazzling pace. More than half of all the nuclear reactors in the world were built between 1970 and 1985.

核能的黄金时代终于在20世纪70年代到来，中东战争使得全球油价猛增。现如今，核能的商业利益和投资以令人惊讶的速度增长。世界上一半的核反应堆建造于1970年和1985年之间。

But which type of reactor to build, given how many different types there were to choose from? A surprising underdog candidate won the day: the light water eactor. It wasn’t very innovative, and it wasn’t too popular with cientists, but it had some decisive advantages: it was there, it worked, and it wasn’t terribly expensive.

然而，在多种可能的反应堆中，到底建造哪种成为了问题。一种看起来并不占优势的反应堆脱颖而出：轻水反应堆。这种科技并非创新，也不是很受科学家欢迎。但是它具有决定性的优势：它已经存在，可以运作，不是很贵那么。

So, what does a light water reactor do? Well, the basic principle is shockingly simple: it heats up water using an artificial chain reaction. Nuclear fission releases several million times more energy than any chemical reaction could. Really heavy elements on the brink of tability, like uranium-235, get bombarded with neutrons. The neutron is absorbed, but the result is unstable. Most of the time, it immediately splits into fast-moving lighter elements, some additional free neutrons, and energy in the form of radiation. The radiation heats the surrounding water, while the neutrons repeat the process with other atoms, releasing more neutrons and radiation in a closely controlled chain reaction. Very different from the fast, destructive runaway reaction in an atomic bomb. In our light water reactor, a moderator is needed to control the neutrons’ energy. Simple, ordinary water does the job, which is very practical, since water’s used to drive the turbines anyway.

轻水反应堆到底怎么工作呢？事实上，它的基本原理特别简单：用人工连锁反应加热水核裂变释放的能量是其他化学反应的数百万倍。一些不稳定重元素，例如铀-235被中子轰击之后会吸收这个中子，但是会形成一种不稳定粒子。大多数时候，它会立即分裂成一些运动速度很快，质量较轻的元素、其他的中子、以及辐射形式的能量。辐射会给周围的水增温，同时分裂出的中子继续这个过程，轰击其他原子，释放更多的中子和辐射。这种反应的收到严格控制，与原子弹快速、不可控、具有毁灭性的反应不同，在轻水反应堆中，会有一个调节器来控制中子的能量。而这个调节器一般就由普通水来担任，因为水可以直接用来驱动涡轮机。

The light water reactor became prevalent because it’s simple and cheap. However, it’s neither the safest, most efficient, nor technically elegant nuclear reactor. The renewed nuclear hype lasted barely a decade, though; in 1979, the Three Mile Island nuclear plant in Pennsylvania barely escaped a catastrophe when its core melted. In 1986, the Chernobyl catastrophe directly threatened Central Europe with a radioactive cloud, and in 2011 the drawn-out Fukushima disaster sparked new discussions and concerns. While in the 1980s 218 new nuclear power reactors went live, their number and nuclear’s global share of electricity production has stagnated since the end of the ’80s.So what’s the situation today? Today, nuclear energy meets around 10% of the world’s energy demand. There are about 439 nuclear reactors in 31 countries. About 70 new reactors are under construction in 2015, most of them in countries which are growing quickly. All in all, 116 new reactors are planned worldwide. Most nuclear eactors were built more than 25 years ago with pretty old technology. More than 80% are various types of light water reactor.

因为简单且廉价，轻水反应堆变得流行起来然而，这即非最安全有效的的，也不是技术上最好的核反应堆然而，可持续核能的美好愿景持续不过十年；1979年，美国宾夕法尼亚州的三里岛核电站部分堆芯融毁，几乎造成灾难性后果。1986年，切尔诺贝利核事故产生的辐射云直接影响了中欧。而2011年的福岛核电站泄漏更是加深了人们的担忧尽管20世纪80年代，共有218所核电站正式运作其数量即国际电力份额自80年代末就止步不前。那么现在是什么情况呢？今天，核电占全球电力的10%在31个国家中，共439个核反应堆2015年，约有70个新反应堆在建，它们大多在迅速发展的国家总之，现在全世界计划建造的反应堆有116个。大多数的核反应堆都有25年了，使用的技术也比较老其中超过80%使用的都是各种轻水反应堆。

Today, many countries are faced with a choice: the expensive replacement of the aging reactors, ossibly with more efficient, but less tested models, or a move away from nuclear power towards newer or older echnology with different cost and environmental impacts.

今天，许多国家都面临一个选择：用昂贵的新设备替代旧反应堆它们可能更加高效，但使用经验不多；或者放弃核能，转而使用其他价格各异，对环境影响也不同的新老技术。