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The Energy Portal
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Welcome to Wikipedia's energy portal, your gateway to the subject of energy and its effects on the world around us. This portal is aimed at educating you about energy and all its uses.

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Energy is a set of physics measures. Popularly the term is most often used in the context of energy as a technology: energy resources, their consumption, development, depletion, and conservation. Biologically, bodies rely on food for energy in the same sense as industry relies on fuels to continue functioning. Since economic activities such as manufacturing and transportation can be energy intensive, energy efficiency, energy dependence, energy security and price are key concerns. Increased awareness of the effects of global warming has led to global debate and action for the reduction of greenhouse gases emissions; like many previous energy use patterns, it is changing not due to depletion or supply constraints but due to problems with waste, extraction, or geopolitical scenarios.

In the context of natural science, energy can take several different forms: thermal, chemical, electrical, radiant, nuclear, etc. These are often grouped as being either kinetic energy or potential energy. Many of these forms can be readily transformed into another with the help of a device - from chemical energy to electrical energy using a battery, for example. Most energy available for human use ultimately comes from the sun, which generates it with nuclear fusion. The enormous potential for fusion and other basic nuclear reactions is expressed by the famous equation E = mc2.

The concepts of energy and its transformations are useful in explaining natural processes on larger scales: Meteorological phenomena like wind, rain, lightning and tornadoes all result from energy transformations brought about by solar energy on the planet. Life itself is critically dependent on biological energy transformations; organic chemical bonds are constantly broken and made to make the exchange and transformation of energy possible. Read more...

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Selected article

Nuclear power is the controlled use of nuclear reactions to release energy for work including propulsion for ships and submarines, and for the generation of electricity. Nuclear energy is produced by a controlled nuclear chain reaction and creates heat which is used to boil water, produce steam, and drive a turbines.

Nuclear power provides around 14% of the world's electricity, 57% of which is generated by the United States, France, and Japan. Nuclear energy policy differs between countries, and some countries have no active nuclear power stations, or have phased them out. The first nuclear generated electricity, used to power four 200-watt light bulbs, was produced at the EBR-I reactor near Arco, Idaho, in 1951. This was followed in 1954 by the first grid-connected plant (in the USSR), and in 1956 by the first commercial plant (in the United Kingdom).

During the last decades of the 20th century, concerns about nuclear waste, nuclear accidents, radiation and nuclear proliferation lead to an anti-nuclear movement. The 1979 Three Mile Island accident and the 1986 Chernobyl disaster also played a part in stopping new plants in many countries, while the economics of nuclear generation and of nuclear decommissioning have also been factors. Despite this, many countries including Japan, China and India have continued to remain active in developing nuclear power, while recent years have seen a renewal of interest in others, including Finland, France, the United States the United Kingdom. Germany, in contrast, will close its 19 nuclear plants by 2020, and is investing heavily in renewable energy instead. Read more...

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Selected picture

Lightning in Arlington.jpg

Photo credit: Postdlf
Lightning is a highly visible form of energy transfer.

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Did you know?

  • According to research by the IPCC, government funding for most energy research programmes has been flat or declining for nearly 20 years, and is now about half the 1980 level?
Cyclone Catarina from the ISS on March 26 2004.JPG
  • Ordinary fossil fuel power plants convert between 36% and 48% of the fuel's energy into electricity, with the remainder being lost as waste heat, about half of which is unavoidable due to the second law of thermodynamics?

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Selected biography

Nikola Tesla (10 July 1856 – 7 January 1943) was an inventor, physicist, mechanical engineer, and electrical engineer. He is best known for his revolutionary contributions to the discipline of electricity and magnetism in the late 19th and early 20th century, which formed the basis of modern alternating current electric power (AC) systems, including the polyphase power distribution systems and the AC motor.

In 1884, Edison hired Tesla to work for his company Edison Machine Works. Tesla's work for Edison began with simple electrical engineering and quickly progressed to solving the company's most difficult problems. Tesla was offered the task of a complete redesign of the Edison company's direct current generators.

In 1887, he constructed the initial brushless alternating current induction motor, which he demonstrated to the American Institute of Electrical Engineers (now IEEE) in 1888. In the same year, he developed the principles of his Tesla coil and began working with George Westinghouse at Westinghouse Electric & Manufacturing Company's Pittsburgh labs. In April of 1887, Tesla began investigating what would later be called X-rays using his own single node vacuum tubes. This device differed from other early X-ray tubes in that they had no target electrode. The modern term for the phenomenon produced by this device is bremsstrahlung (or braking radiation). He performed several experiments prior to Roentgen's discovery (including photographing the bones of his hand; later, he sent these images to Roentgen) but didn't make his findings widely known; much of his research was lost in the 5th Avenue lab fire of March 1895. Read more...

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