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Welcome to Wikipedia's Energy portal, your gateway to energy. This portal is aimed at giving you access to all energy related topics in all of its forms.
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The Sun is the ultimate source of energy for most of life on Earth.  It derives its energy mainly from nuclear fusion in its core, converting mass to energy as protons are combined to form helium. This energy is transported to the sun's surface and released into space (mainly in the form of radiant (light) energy).
The Sun is the ultimate source of energy for most of life on Earth. It derives its energy mainly from nuclear fusion in its core, converting mass to energy as protons are combined to form helium. This energy is transported to the sun's surface and released into space (mainly in the form of radiant (light) energy).

In physics, energy is the quantitative property that must be transferred to a body or physical system to perform work on the body, or to heat it. Energy is a conserved quantity; the law of conservation of energy states that energy can be converted in form, but not created or destroyed. The unit of measurement in the International System of Units (SI) of energy is the joule, which is the energy transferred to an object by the work of moving it a distance of one metre against a force of one newton.

Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object's position in a force field (gravitational, electric or magnetic), the elastic energy stored by stretching solid objects, the chemical energy released when a fuel burns, the radiant energy carried by light, and the thermal energy due to an object's temperature.

Mass and energy are closely related. Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy. For example, after heating an object, its increase in energy could in principle be measured as a small increase in mass, with a sensitive enough scale.

Living organisms require energy to stay alive, such as the energy humans get from food and oxygen. Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The processes of Earth's climate and ecosystem are driven by the radiant energy Earth receives from the Sun and the geothermal energy contained within the earth. (Full article...)

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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 (fission) power stations, provided 11% of the world's electricity in 2012, somewhat less than that generated by hydro-electric stations at 16%. 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 led to an anti-nuclear movement. The 1979 Three Mile Island accident, the 1986 Chernobyl disaster, and the 2011 Fukushima 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, some countries including China and India have continued to remain active in developing nuclear power, Germany will close its 19 nuclear plants by 2020, and is investing heavily in renewable energy commercialization instead.

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Photo credit: Andreas Tille
Geysers erupt periodically due to surface water being heated by geothermal heat.

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  • 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?
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William Thomson, 1st Baron Kelvin, OM, GCVO, PC, PRS, FRSE, (26 June 1824 – 17 December 1907), widely known for developing the Kelvin scale of absolute temperature measurement, was a mathematical physicist, engineer, and outstanding leader in the physical sciences of the 19th century. He did important work in the mathematical analysis of electricity and thermodynamics, and did much to unify the emerging discipline of physics in its modern form.

Born in Ireland, Thomson studied at the University of Glasgow, Scotland. On graduating, he became a mathematics teacher at the Royal Belfast Academical Institution. During his life Thomson published more than 600 scientific papers and filed over 70 patents.

As early as 1845 Thomson pointed out that the experimental results of William Snow Harris were in accordance with the laws of Coulomb. Over the period 1855 to 1867, Thomson collaborated with Peter Guthrie Tait the Treatise on Natural Philosophy that unified the various branches of physical science under the common principle of energy. His inventions included the current balance for the precise specification of the ampere, the standard unit of electric current.

In 1893, Thomson headed an international commission to decide on the design of the Niagara Falls power station. Despite his previous belief in the superiority of direct current electric power transmission, he agreed to use alternating current after seeing a Westinghouse demonstration at the Chicago World's Fair.

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In the news

1 December 2021 – Aftermath of COP26
Micronesian president David W. Panuelo condemns the outcome of the climate summit, stating that industrialized nations must increase their commitments in order to help countries switch from fossil fuels to renewable energy. (Reuters)
25 November 2021 – Turkey–United Arab Emirates relations
Turkey and the United Arab Emirates sign several investment accords during a high-level visit to Ankara by Abu Dhabi Crown Prince Mohammed bin Zayed Al Nahyan, including a $10 billion investment fund to support the Turkish health and energy sectors. The Turkish and Emirati central banks also sign a cooperation agreement. (Reuters)

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