THE NUCLEAR ENERGY CHALLENGE

The atom, the smallest component of any element, contains enormous energy. When it is split – a process called fission, this energy is released in the forms of tremendous heat and light. This energy was released on Hiroshima and Nagasaki, Japan, by two separate atom bombs in 1945 that led to the conclusion of World War II. The horrors created by those two bombs led the international community to condemn further use of atomic weapons.

Still, engineers, governments and scientists realized that if the atom's energy could be controlled and harnessed, it would revolutionize the world's energy markets and provide significant electricity reserves to help meet the world's energy demands. It was even envisioned that it could one day replace the need for fossil fuels.

As a result, the first usable electricity from nuclear fission was produced at the Idaho National Engineering Laboratory in 1951.

In 1954, The Atomic Energy Act was passed to promote the peaceful use of nuclear energy. Subsequently, in 1957, the International Atomic Energy Agency (IAEA) was formed to promote peaceful use of nuclear energy and to provide international safeguards and an inspection system to ensure nuclear materials are not diverted from peaceful to military uses. It was later replaced by the Nuclear Regulatory Commission and the Energy Research and Development Administration, the latter of which became the US Department of Energy in 1977.

Commercial nuclear power plants became a commercial reality in the late 1960s when large numbers of orders were placed for nuclear power reactors in the United States. Yet, in 1979, America's fears about nuclear power were realized when a partial meltdown occurred in a reactor at the Three Mile Island facility in Harrisburg, Pennsylvania. Though minimal radioactive material – which can cause serious damage to or kill living tissue – was released, the potential for greater disaster lurked.

This greater potential was realized in April 1986 when a full reactor meltdown and fire occurred at the Chernobyl Nuclear Power Plant in the former Soviet Union. This resulted in the massive release of radioactive materials, resulting in major environmental catastrophe. As a result of these disasters, global support for nuclear

energy – which already had significant negative public support – plummeted to lower levels. Over the last 15 years, vast improvements to nuclear reactors have been made to make them safer and last longer. There is still strong support for nuclear energy from many sectors that are convinced it is the future of the world's energy sources. While nuclear energy has several advantages over fossil fuels, particularly considering that it does not release the harmful greenhouse gas carbon dioxide into the atmosphere, public resistance remains high.

Nuclear energy requires sources of radioactive elements found naturally in our environment and manmade with which to create the nuclear fission process that splits the atoms. The most common and most used of these elements is Uranium, which is found in two different types or species (called isotopes): U-238 and U-235. U-235 is the type used for nuclear fission because it can be readily split, releasing massive energy. The other type of Uranium is called U-238, which is barely radioactive. Of all the known Uranium reserves in the world, almost all of it is U-238, with just over a half a percent of those reserves being U-235. Plutonium and Thorium are the only other available sources that are used for nuclear energy. Plutonium is not naturally occurring. Thus, the Plutonium used in nuclear reactors is man-made, coming from a nuclear reactor. It is not as stable as U-235 and is harder to use. Thorium, though not yet a mainstream nuclear energy supply source, is being heavily studied and applied as a safer, cleaner alternative to Uranium. Still, Uranium is king as the premiere provider of nuclear energy.

Perhaps the greatest challenge facing nuclear energy production – after any potential for nuclear disasters similar to the 1986 Chernobyl event – is disposal of the highly radioactive wastes. It could take at least 10,000 years for these materials to fully break down into harmless elements so the challenge is to store them safely for at least that length of time. It is possible, but where and how are still troubling issues. Exploitable Uranium supplies also pose some more short-term challenges. According to the Organization for Economic Cooperation and Development, the world's economically exploitable Uranium reserves are likely to last between 35 and 63 years, depending on whether demand is such as to justify the higher cost of mining less easily exploitable reserves. Still, in consideration of the power that can be generated by Uranium and the burgeoning global energy demands, many governments are placing more emphasis on nuclear energy. The largest user of nuclear energy is the United States, followed by France, Japan, Germany and the Russian Federation. In the US alone, the nation's 103 nuclear power plants each generate an average of around 20 tons of radioactive spent fuel a year.

Spent fuel now sits in cooling pools and temporary storage areas waiting for somebody to figure out what to do with it.

A second form of nuclear energy comes from the same process that gives life to our sun and other stars in the universe: nuclear fusion. Fusion occurs when two lighter elements, like hydrogen, are forced together – or fused – to create a heavier element, Helium. This occurs only under extraordinary heat and pressure, but it releases enormous energy in the form of heat, light and other radiation. Deep inside the sun's core, hydrogen is converted to helium at temperatures of 10 – 15 million degrees Celsius. Fusion provides the energy necessary to sustain life on Earth. Sunlight is energy released from fusion reactions inside the sun. This process also produces all of the chemical elements found on Earth. In 1952, seven years after the atomic bombs were dropped on Japan, the United States developed and successfully tested the hydrogen bomb. Using the same fusion process and hydrogen elements used in the sun and stars, the hydrogen bomb yields thousands of times more energy than that provided by nuclear fission. One hydrogen bomb would release five times more energy than all of the bombs dropped in World War II! Fortunately, there have been no hydrogen bombs used in warfare.

Duplicating the fusion process that is constantly occurring inside the Sun is not that easy. While fusion does not have the harmful radiation side effects that fission creates, the problem with nuclear fusion is to start the fusion reaction in an area small enough at sufficiently high temperatures – about 180,000,000 degrees Fahrenheit!

There is currently no known substance that would not melt or vaporize at just a few thousand degrees.

Words and Expressions to remember:

a fission – расщепление, деление атомного ядра при цепной реакции

to condemn – браковать, признавать негодным для использования

to envision – воображать что-либо, представлять себе, предвидеть

to divert – отвлекать, переключать, переводить

a meltdown – расплавка, растворение

a facility – оборудование, приспособление, аппаратура

a tissue – ткань, материя

to lurk – скрываться в засаде, прятаться

to plummet – кидать, бросать, швырять вниз, сбивать

an isotope – изотоп

a mainstream – основное направление, главная тенденция

a premiere – премьера

exploitable – использующийся

to burgeon – распускаться, расцветать

a fusion – синтез, слияние

to yield – давать такой-то результат, приводить к чему-либо

a warfare – война, приемы ведения войны

to duplicate – повторять, копировать

to vaporize – испаряться, распылять

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