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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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Introduction
In physics, energy (from Ancient Greek: ἐνέργεια, enérgeia, “activity”) 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 for energy in the International System of Units (SI) is the joule (J). It is defined as-
"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 (for instance due to its position in a field), the elastic energy stored in a solid object, chemical energy associated with chemical reactions, the radiant energy carried by electromagnetic radiation, and the internal energy contained within a thermodynamic system. All living organisms constantly take in and release energy.
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.
Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The Earth's climates and ecosystems have processes that are driven either by the energy the planet receives from the Sun or by geothermal energy. (Full article...)
Selected article
The use of coal dates back to the Bronze Age, but it was the Industrial Revolution that led to its large-scale use, as the steam engine took over from the water wheel. Today world coal consumption is about 5.3 billion tonnes annually, of which about 75% is used to produce electricity. The region including the China and India uses about 1.7 billion tonnes annually, forecast to exceed 2.7 billion tonnes by 2025. The United States consumes about 1.0 billion tons annually. Almost one-third of all coal used was supplied by China in 2005.
Coal mining causes a number of harmful effects, including the pollution of water sources by sulfuric acid caused by a chemical reaction between water and iron sulfide in the coal. In common with other fossil fuels, the burning coal produces carbon dioxide and nitrogen oxides. It also produces sulfur dioxide, the cause of acid rain. Coal contains traces of uranium, thorium, and other naturally-occurring radioactive isotopes which, due to the vast quantities of coal used, cause more radioactive contamination than nuclear power plants. To eliminate CO2 emissions from coal plants, carbon capture and storage technology has been proposed but has yet to be commercially used.
Selected image
Photo credit: From an image by Wolfgang Beyer
Strombolian volcanic eruptions can eject incandescent cinder, lapilli and lava bombs to altitudes of tens to hundreds of meters.
Did you know?
- The Power of Community: How Cuba Survived Peak Oil is a documentary film which details Cuba's efforts to recover from the 1990s economic crisis known as the Special Period?
- The Geysers (pictured), north of San Francisco, California, is the largest geothermal power development in the world?
- The International Energy Agency was founded in 1974 by the Organisation for Economic Co-operation and Development (OECD) in the wake of the 1973 oil crisis?
- Indian Railways has started to use Jatropha oil, blended with diesel fuel in various ratios, to power its Diesel locomotives?
- The South Wales Gas Pipeline is the largest high pressure gas pipeline in the United Kingdom?
- The Presbyterian Church (USA) was the first major religious denomination in the world to call on its followers to become carbon neutral?
- There was partial meltdown at the Three Mile Island nuclear power plant in 1979?
- A hybrid electric vehicle achieves better fuel economy than a conventional vehicle without being hampered by the limited range of an electric vehicle?
Selected biography
Rockefeller founded the Standard Oil Company in 1870 and ran it until he retired in the late 1890s. He continued to retain his stock and his title as president until 1911, when the company was broken up for carrying out illegal monopoly practices. The new companies formed included the predecessors of Conoco, Amoco, Chevron, Esso, Mobil and Sohio. Rockefeller, who had rarely sold shares, owned stock in all of them. As gasoline had grown in importance his wealth had soared and he became the world's richest man and the first billionaire.
Rockefeller's fortune was used to create the modern systematic approach of targeted philanthropy with foundations that had a major impact on medicine, education, and scientific research. His foundations pioneered the development of medical research, and was instrumental in the eradication of hookworm and yellow fever. At his death, at the age of 98, Rockefeller's remaining fortune was estimated at $1.4 billion. As a percentage of the United States economy, no other American fortune has ever come close.
In the news
- 27 August 2022 – Hungary–Russia relations, Nuclear power in Hungary
- Minister of Foreign Affairs Péter Szijjártó announces Russian nuclear energy provider Rosatom will begin construction of two new nuclear reactors to expand the Paks Nuclear Power Plant. (BBC News)
- 5 August 2022 – Economic impact of the 2022 Russian invasion of Ukraine
- Russian President Vladimir Putin signs a decree banning investors from "unfriendly countries" from selling their assets in Russian banks, strategic entities, and energy and commodity projects until December 31. (Reuters)
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Quotations
- "Without radical international measures to reduce carbon emissions within the next 10 to 15 years, there is compelling evidence to suggest we might lose the chance to control temperature rises. Failure to act will make an increase of between 2 and 5 degrees [3.6 - 9°F] in average temperatures almost inevitable." – Tony Blair, 2006
- "The question is not whether climate change is happening or not, but whether, in the face of this emergency, we ourselves can change fast enough." – Kofi Annan, 2006
- "I promise you a day will come when our children and grandchildren will look back and they will ask one of two questions. Either they will ask, 'What in God's name were they doing? Didn't they see the evidence?' Or, they may look back and say 'How did they find the uncommon moral courage to rise above politics and redeem the promise of American democracy?'" – Al Gore, 2007, on global warming.
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