From Wikipedia, the free encyclopedia
Main pageNew articles & Tasks
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.
Page contents: Selected articleSelected imageSelected biographyDid you know?General imagesQuotationsRelated portalsWikiprojectsMajor topicsCategoriesHelpAssociated Wikimedia


A plasma lamp, 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...)

Selected article

The Northwest Exelon Pavilion is the Millennium Park Welcome Center and houses the park's office.

The Exelon Pavilions are four buildings that generate electricity from solar energy and provide access to underground parking in Millennium Park in the Loop community area of Chicago in Cook County, Illinois, United States. The Northeast Exelon Pavilion and Northwest Exelon Pavilion (jointly the North Exelon Pavilions) are located on the northern edge of the park along Randolph Street, and flank the Harris Theater. The Southeast Exelon Pavilion and Southwest Exelon Pavilion (jointly the South Exelon Pavilions) are located on the southern edge of the park along Monroe Street, and flank the Lurie Garden. Together the pavilions generate 19,840 kilowatt-hours (71,400 MJ) of electricity annually, worth about $2,350 per year.

The four pavilions, which cost $7 million, were designed in January 2001; construction began in January 2004. The South Pavilions were completed and opened in July 2004, while the North Pavilions were completed in November 2004, with a grand opening on April 30, 2005. In addition to producing energy, three of the four pavilions provide access to the parking garages below the park, while the fourth serves as the park's welcome center and office. Exelon, a company that generates the electricity transmitted by its subsidiary Commonwealth Edison, donated $5.5 million for the pavilions. Chicago Tribune architecture critic Blair Kamin praised the South Pavilions as "minor modernist jewels", but criticized the North Pavilions as "nearly all black and impenetrable". The North Pavilions have received the Leadership in Energy and Environmental Design (LEED) silver rating from the United States Green Building Council, as well as an award from the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). (Full article...)

Selected image

Did you know?

SEGS solar power plant
SEGS solar power plant
  • The concentration of the greenhouse gas carbon dioxide has increased from about 280 parts per million to about 380 ppm since the start of the Industrial Revolution. That's an increase of 35.71%. The estimated population of the world in 1750 was 791 Million people. The estimated population of the world on June 30th, 2007 was 6.6 Billion people. That's an increase of 734.39%.?
  • In the 1990s Bougainville conflict, islanders cut off from oil supplies due to a blockade used coconut oil to fuel their vehicles?

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

9 September 2023 – Russian invasion of Ukraine
The International Atomic Energy Agency warns of a nuclear threat at the Zaporizhzhia Nuclear Power Plant after explosions were heard near the plant amidst the Ukrainian counteroffensive. (PBS News)
28 August 2023 – Russian Invasion of Ukraine
The International Atomic Energy Agency warns that Ukraine's offensive in Zaporizhzhia Oblast has increased the risk of damage to the Zaporizhzhia Nuclear Power Plant. (Al Jazeera)
25 August 2023 –
A U.S. federal control board files a new plan for restructuring $10 billion in debt owned by Puerto Rico’s power company in an attempt to end bankruptcy negotiations. (AP)

General images

The following are images from various energy-related articles on Wikipedia.


Related portals


Major topics


Puzzled by energy?
Can't answer your question?
Don't understand the answer?

For further ideas, to leave a comment, or to learn how you can help improve and update this portal, see the talk page.

Associated Wikimedia

The following Wikimedia Foundation sister projects provide more on this subject:

Discover Wikipedia using portals

Purge server cache