Nuclear power plants have many different designs and shapes. Early technology restrictions in nuclear power plants make huge plants with the capability to produce the greatest amount of power possible. But with more recent technology, nuclear plants size are smaller , making them less costly and easier to build. But despite their many technical and engineering differences, nuclear reactors come in two basic types: pressurized water reactor systems and boiling water reactor systems.
Pressurized water reactor system
One system in common use is called the pressurized water reactor system. As the name implies, it relies on water under pressure to produce the heat needed for electricity production. In such a system, the fuel rods are inserted into a steel pressure tank that contains ordinary water. In this case, water acts as a cooling agent, but it also moderates the reaction because it can absorb neutrons. Sticking out — or Protruding— through the lid of the pressure tank are the control rods.
The chain reaction begins as the control rods are slowly pulled out, The reaction produces heat, which heats the water in the pressure tank. The hot water steam heating heats to 518 Fahrenheit (270 Celsius).
The water power sources does not boil, though, because it is under intense pressure. The heated water is then channeled to a heat exchanger in a closed circuit. The water in the heat exchanger is then heated up, producing steam. The steam drives a turbine generator that is little different in principle from a turbine used in a homemade windmill or a hydroelectric dam. As the magniwork generator turns, it produces electricity. Meanwhile, the steam is condensed, usually by cool water from a lake or river, and returned to the heat exchanger.
Boiling water reactor system
The other major system, the boiling water reactor system, is more efficient than the pressurized water reactor system. One noticeable difference is that with a boiling water system, the control rods protrude from the bottom of the containment chamber. Inside the chamber is the reactor core. The control rods are at the bottom because the water inside the chamber is allowed to boil. The steam created by the boiling water is allowed to rise to the top of the chamber. Pipelines carry the steam directly to the turbines, where its heat transmission causes them to turn electricity generation. The steam then condenses and is channeled back into the containment chamber. Underneath the reactor is a circular tunnel filled partway with water. This tunnel is a safety mechanism. If any steam or water were to escape from the containment chamber, it would fall into the tunnel, where it could do no immediate harm.
The possibility of nuclear fusion
Scientists look forward to the discovery of a power source that is clean, safe, universally available at all times to all people throughout the world, and that uses a fuel that is abundant, cheap, and efficient. It would not contribute to greenhouse global warming or air pollution, require large plants that would disrupt the natural environment, or produce dangerous by-products. To that end, some scientists conduct research into what is called ‘‘cold fusion.’’ Cold fusion uses fuel that is commonly available from the hydrogen production water. However, governments have favored a more conventional approach to fusion at extremely high temperatures.
Nuclear fission refers to the splitting, or breaking apart, of atoms. Nuclear fusion, as the name suggests, involves the fusing, or joining together, of atoms. The light nuclear of two atoms bind together during nuclear fusion to form a single heavier nucleus. One example is the deuteron, a single particle formed by the combination of a neutron and a proton. When a deuteron or similar particle is formed, its mass is generally less than the total mass of the two original particles. The mass that disappears is released as energy. What appeals to scientists seeking to harness nuclear fusion is that such reactions occur in nature throughout the universe, particularly in stars. Fusion takes place in stars because of their high temperatures, up to 18,000,032 Fahrenheit (10 million Celsius), possibly even hundreds of millions of degrees. The problem is that while such high temperatures can be found in the center of stars, including the Earth’s sun, they do not occur naturally on Earth.
Several fusion reactors have been built, but as yet none has ‘produced’ more thermal energy than electrical energy consumed. Despite research having started in the 1950s, no commercial fusion reactor is expected before 2050.
So far, fusion experiments have failed to produce any power in excess of the power needed to produce the fusion reaction. In other words, there was a net power loss. For many scientists, the enormous energy demands of hot fusion make it impractical. Instead, they have searched for a way to create fusion reactions at low temperatures, called ‘‘cold fusion.’’ Cold fusion is a term coined in 1986 by Dr. Paul Palmer of Brigham Young University in Utah. It is the popular term for what scientists call ‘‘low energy nuclear reactions’’ in a field that is sometimes called ‘‘condensed matter nuclear science’’ in nuclear research & development.
Meanwhile, many scientists have made claims that they have produced cold fusion. Some of the most prominent researchers in the field are in Japan, where the level of funding for cold fusion research is much higher than it is in the United States. At Japan’s Hokkaido University, for example, D. T. Munzo reported experiments in which the ratio of energy output to energy input was seventy thousand to one. As of 2005, though, the world seemed decades away from seeing a commercial fusion reactor, whether hot or cold.
