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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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A plasma globe, using electrical energy to create plasma, light, heat, movement and a faint sound

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).

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 climate and ecosystems processes are driven by the energy the planet receives from the Sun (although a small amount is also contributed by geothermal energy). (Full article...)

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Global warming is the increase in the average temperature of the Earth's near-surface air and oceans in recent decades and its projected continuation. Global average air temperature rose 0.74 ± 0.18 °C (1.3 ± 0.32 °F) during the past century. The Intergovernmental Panel on Climate Change concludes, 'most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations.'

The effects of global warming are expected to include sea level rise, floods, drought and changes in the frequency and intensity of extreme weather events. Other effects may include changes in agricultural yields, reduced summer streamflows, species extinctions and increases in the ranges of disease vectors.

Concentrations of greenhouse gases are now considerably higher than at any time during the last 650,000 years, the extent of the ice core record. It is believed that CO2 concentrations were last this high 20 million years ago. The primary international agreement on combating global warming is the Kyoto Protocol, which covers more than 160 countries and over 55% of global greenhouse gas emissions. The United States, the world's largest greenhouse gas emitter; Australia; 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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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
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?

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John Davison Rockefeller, Sr. (July 8, 1839 – May 23, 1937) was a controversial American industrialist who revolutionized the oil industry and defined the structure of modern philanthropy. He is often regarded as the richest person in history.

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.

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