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  • 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.

  • 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.

  • 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.

  • 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.

  • 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 reactor.

  • It wasn’t very innovative, and it wasn’t too popular with scientists,

  • but it had some decisive advantages:

  • it was there, it worked, and it wasn’t terribly expensive.

  • 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 stability, 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 neutronsenergy.

  • Simple, ordinary water does the job, which is very practical, since water’s used

  • to drive the turbines anyway.

  • 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 reactors were built more than 25 years ago with pretty old technology.

  • More than 80% are various types of light water reactor.

  • Today, many countries are faced with a choice: the expensive replacement of

  • the aging reactors, possibly with more efficient, but less tested models,

  • or a move away from nuclear power towards newer or older technology

  • with different cost and environmental impacts.

  • So, should we use nuclear energy?

  • The pro and contra arguments will be presented here next week.

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  • Subtitles by the Amara.org community

Have you ever been in an argument about nuclear power?

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