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The Energy Portal
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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A plasma lamp, using electrical energy to create plasma light, heat, movement and a faint sound
A plasma lamp, using electrical energy to create plasma light, heat, movement and a faint sound

In physics, energy is the quantitative property that is transferred to a body or to a physical system, recognizable in the performance of work and in the form of heat and light. 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. 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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According to Hubbert peak theory, peak oil is the date when the peak of the world's production of conventional petroleum (crude oil) is reached. After this date the rate of production is forecast to enter terminal decline, following the bell-shaped curve predicted by the theory. Due to the world's high dependence on inexpensive oil, it is thought that severe price increases may result, with serious implications for the global economy.

Acceptance of peak oil is far from universal, and the only reliable way to identify its existence will be in retrospect. One alternative scenario is that global production will eventually follow an 'undulating plateau' for one or more decades before declining slowly.

Having accurately predicted the date of peak production in the US petroleum industry, which occurred in 1970, M. King Hubbert, who devised the theory, forecast that the world peak would occur in 1995 'if current trends continue'. Various subsequent predictions have been made as trends have fluctuated in the intervening years. Two milestones have passed, however. The peak of world oilfield discoveries occurred in 1965 and, due world population growth, production per capita peaked in 1979.

The effects of peak oil could be mitigated through conservation and switching to alternative fuels or unconventional oil sources. Such changes would bring their own challenges, ranging from the need to development alternative technologies to potential increases in greenhouse gas emissions.

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Photo credit: Björn Appel
A solar furnace can be used to generate electricity, melt steel or make hydrogen fuel.

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Enrico Fermi (September 29, 1901 – November 28, 1954) was an Italian physicist most noted for his work on the development of the first nuclear reactor, and for the development of quantum theory. Fermi won the 1938 Nobel Prize in Physics for his work on induced radioactivity.

Fermi was well-known for his simplicity in solving problems. Whenever possible, he avoided complicated mathematics and obtained quick results based on order of magnitude estimates. Fermi also meticulously recorded his calculations in notebooks, and later used to solve many new problems that he encountered based on these earlier known problems.

After accepting the 1938 Nobel Prize in Stockholm, Fermi immigrated to New York with his family to escape the anti-Semitic laws of Fascist Italy, as his wife Laura was Jewish.

After working at Columbia University, Fermi went to the University of Chicago and began studies that led to the construction of the world's first nuclear reactor Chicago Pile-1 (CP-1). The first artificial, self-sustaining, nuclear chain reaction was initiated within CP-1, on December 2, 1942.

In the news

21 June 2022 – 2021–2022 global energy crisis
Lebanon, Egypt and Syria sign an agreement to supply Egyptian gas to a power plant in northern Lebanon through Syria. However, the World Bank, which is financing the deal, must validate the agreement before it can take effect. (The Independent)
20 June 2022 – 2022 Russia–European Union gas dispute
Dutch climate and energy minister Rob Jetten announces that the Netherlands will remove all restrictions on the operation of coal-fired power stations until at least 2024, in response to Russia's refusal to export natural gas to the country. Operations were previously limited to less than a third of the total production. (CNA)

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