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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

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 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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Climate change mitigation involves taking actions aimed at reducing the extent of global warming. This is in contrast to adaptation to global warming which involves minimizing the effects.

To avoid dangerous climate change, the energy policy of the European Union has set a 2°C [3.6°F] limit to the temperature rise, compared to pre-industrial levels. Of this, 0.8°C has already taken place and another 0.5°C is already committed. The 2°C rise is associated with a carbon dioxide concentration of 400–500 ppm by volume; as of January 2007 it was 383 ppm by volume, and rising at 2 ppm annually. Unless significant action is taken soon the 2°C limit is likely to be exceeded.

Strategies for moving to a low-carbon economy include development of new technologies, particularly renewable energy; electric and hybrid vehicles; fuel cells; public transportion; zero-energy buildings; Zero-Net-Energy USA Federal Buildings; energy conservation; carbon taxes; enhancing natural carbon dioxide sinks; population control; and carbon capture and storage. Environmental groups also encourage individual-lifestyle and political action, as well as action by business.

The Kyoto Protocol, covering more than 160 countries and over 55% of global emissions provides an international mitigation framework. The United States, the world's largest greenhouse gas emitter; and Kazakhstan have refused to ratify the treaty. China and India, two other large emitters, have ratified the treaty but are exempt from cutting emissions. International talks on a successor to the treaty, which ends in 2012, have begun.

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Apollo 11 Saturn V lifting off on July 16, 1969.jpg

Photo credit: NASA
A Saturn V rocket launches Apollo 11, burning 3,580 U.S. gallons (13,552 liters) of kerosene per second.

Did you know?

A compact fluorescent lamp
  • Positive lightning bolts are typically six to ten times more powerful than normal lightning — and aircraft are not designed to withstand them?
  • Dark energy is a hypothetical form of energy which permeates all of space?

Selected biography

James E. Hansen (born March 29, 1941) heads the NASA Institute for Space Studies and is currently an adjunct professor in the Earth and Environmental Sciences department at Columbia University. He is best known for his testimony on climate change to congressional committees in the 1980s that helped raise broad awareness of global warming.

Hansen studied at the University of Iowa, obtaining a B.A. in Physics and Mathematics, an M.S. in Astronomy and a Ph.D. in Physics. He was elected to the National Academy of Sciences in 1996 and received the Heinz Environment Award for his research on global warming in 2001.

Hansen is a vocal critic of the Bush Administration's ideology on climate change. In 2005 and 2006, he claimed that NASA administrators have tried to influence his public statements about the causes of climate change. He has also claimed that the White House edited climate-related press releases from federal agencies to make global warming seem less threatening, and that he is unable to speak 'freely', without the backlash of other government officials.

Hansen has said that a global tipping point will be reached by 2016 if levels of greenhouse gases are not reduced. After this point global warming becomes unstoppable. As a result he claims that there may be a rise in sea levels by as much as 10 feet (3 metres) by 2100.

In the news

13 May 2022 – Enlargement of NATO
RAO Nordic, a subsidiary of Russian energy company Inter RAO, announces it will suspend deliveries of electricity to Finland, saying it has not been paid for prior deliveries. The suspension comes as Russia threatens retaliation if Finland joins NATO. (BBC News)
1 May 2022 – International sanctions during the Russo-Ukrainian War
Hungary, a member of the European Union, says that it will veto any sanctions that would restrict energy imports from Russia. Unanimity among the 27 EU members is required to introduce sanctions. (Bloomberg)
27 April 2022 – Russia in the European energy sector
2022 Russia–European Union gas dispute
Gazprom announces that it has "completely suspended gas supplies" to the gas companies of Poland and Bulgaria "due to [the] absence of payments in roubles". Bulgaria, Poland, and the European Union condemn the suspension. (Reuters) (Reuters)
The suspension of gas to Poland and Bulgaria causes natural gas prices to increase and also causes the Russian ruble to reach a 2 year high against the Euro in Moscow trade. (Reuters) (Reuters) (Natural Gas Intelligence)

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