Scientific and technical understanding of energy has allowed us to generate, transmit and use electricity to heat homes, charge phones, light streets and so much more. In the U. As modern society became electrified there developed a network of power plants, transmission lines, substations and other components of an electricity transmission and distribution system. This interactive explainer is featured in our Energy e-book series. After the voltage leaves the generator, it heads to the transmission substation.
Already high voltage, the large transformers within the substation further ramp it up to extremely high levels around ,, volts.
This is essential for its efficient transmission towards its end destination your home. It must go through a step-down process a reduction of voltage for safety. After transformers reduce voltage to lower levels, it is more safely distributed locally.
But it must be pared-down again for safety before being carried into your home. This happens via hanging transformers conveniently attached to distribution lines. The electricity supply cable enters your home through a meter which records how much electricity you are using and a consumer unit or fusebox where your main switch and residual current devices RCDs are located.
Finally, your domestic wiring distributes electricity to lights and sockets throughout your home. Many people do not recognise equipment on the electricity network, for example, a common misunderstanding is that cables on wooden poles are telephone wires but often they are electricity power lines.
Click here to see photographs of equipment on the electricity network. Electricity distribution companies are responsible for the network of power lines, underground cables, substations etc. Hydropower became widely used in the early s when technology to transmit electricity over long distances was developed. The water in the reservoir is considered stored energy.
A greater amount of head translates to more available energy for electrical generation. The rotating turbine in turn drives the generator. As America looks for clean energy solutions, there is one form of efficient, clean power production that our nation has not explored for the last 57 years—nuclear.
Compared to other countries using nuclear power production more readily, the U. Each nuclear power plant typically employs to people. Although nuclear power is efficient, it takes many steps to get it into a usable form of energy for your home. Below we look at what it takes to use a fuel, such as uranium, and to convert it into power for your home. The production of nuclear power begins in the mines—where miners search for uranium ore which serves as the fuel for nuclear power production.
Uranium miners use several techniques to obtain this chemical element: surface open pit , underground and in-situ leach mining. Underground Uranium mining requires the same basic steps as required for any other type of mining— such as coal.
The final product of milling creates yellowcake named for its powdery texture and yellowish color. The drums of yellowcake must go through yet another process to be transformed into a fuel that can be used by power plants. Natural uranium is composed of two types: U and U Only U is capable of being used for energy production, but it only makes up less than 1 percent of natural uranium. To understand how enrichment works, picture the gaseous molecules as sand particles suspended in air.
All molecules are blown through thousands of filters or sieves, one after another. Because the lighter U particles travel faster than the heavier U particles, more of them penetrate each sieve. As more sieves are passed, the concentration of U increases. The process continues until the concentration of U is raised, or enriched, to percent. Before it can be made into nuclear fuel, however, the enriched uranium fluoride gas is changed to uranium dioxide—a solid.
The fuel pellets are inserted and stacked end to end into slender, heat-resistant metallic tubes, or fuel rods which can range in size from feet tall.
The fuel rods are combined to form fuel bundles and on average, fuel bundles each weighing approximately 1, pounds are loaded into each reactor core. As the U is exhausted, fission, or the splitting process of atoms, slows, therefore requiring fuel bundles to be replaced every months.
When the fuel bundles are placed in the reactor, it is the process of the uranium atoms splitting as they are bombarded with free neutrons—also known as fission—that creates energy which is given off as heat. However, control rods made of the chemical element boron are placed into the fuel bundles to slow down or altogether halt the fission of the uranium atoms, giving the power plant the ability to precisely control the amount of heat given off.
Steam generators then take river water and run it against pipes that contain the PWR heated water to convert the river water into steam. The steam is then sent to turbines to begin the electricity power production process. The steam is then released through cooling towers.
In one year a typical nuclear power plant generates 20 metric tons of used nuclear fuel. The nuclear industry generates a total of about 2, metric tons of used fuel per year. During the past four decades, the entire industry has produced about 60, metric tons of used nuclear fuel. If used fuel assemblies were stacked end-to-end and side-by-side, this would cover a football field about seven yards deep.
Most U. Since water is a natural radiation barrier, spent fuel is loaded into airtight steel or concrete-and-steel containers, known as casks, and then carefully delivered to a steel-lined, concrete pool of water for storage. On-site dry storage is done in a similar matter, with the used fuel being placed into engineered concrete and steel casks that are set on a special pad. Each cask can weigh , pounds and is strong enough to take a hit from a fast moving truck or even a train without any damage.
Other countries, such as Japan, Russia and those in Europe, reprocess used spent nuclear fuel by separating uranium and plutonium from the waste products of fuel rods and then re-enrich the recovered uranium to be used again as fuel. In addition to backup systems that monitor and regulate what goes on inside the reactor, U. Everything from the fuel pellets to the fuel rods are encased in materials that limit radiation exposure.
All of these items are further contained in a massive reinforced concrete structure—called the containment—with walls that are four feet thick. The lack of a containment structure is what helped lead to the failure of the Chernobyl plant in Russia, something that cannot happen in the United States since all plants are required to have containment structures and other safety features. It takes many steps to generate electricity produced from nuclear power. However, nuclear power allows us to have a clean, alternative energy source.
When you take into account the planning process which includes meteorological, seismic and population studies, it can take up to years to build a nuclear plant, from planning to operation. But in doing so, an efficient energy source can deliver power to your home. Because of modern technologies, new sources of energy are being used every day.
The four renewable sources used most often are wind, solar photovoltaics, geothermal and biomass. Hydropower is also a renewable resource and is highlighted above. When the wind blows, it flows over the blades creating lift, like the effect on airplane wings, which causes them to turn.
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