Main page | New 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 article • Selected image • Selected biography • Did you know? • General images • Quotations • Related portals • Wikiprojects • Major topics • Categories • Help • Associated Wikimedia |
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; matter and energy may also be converted to one another. 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
High-level radioactive waste management concerns management and disposal of highly radioactive materials created during production of nuclear power and nuclear warheads. The technical issues in accomplishing this are daunting, due to the extremely long periods radioactive wastes remain deadly to living organisms. Of particular concern are two long-lived fission products, Technetium-99 (half-life 220,000 years) and Iodine-129 (half-life 15.7 million years), which dominate spent nuclear fuel radioactivity after a few thousand years. The most troublesome transuranic elements in spent fuel are Neptunium-237 (half-life two million years) and Plutonium-239 (half-life 24,000 years). Consequently, high-level radioactive waste requires sophisticated treatment and management to successfully isolate it from the biosphere. This usually necessitates treatment, followed by a long-term management strategy involving permanent storage, disposal or transformation of the waste into a non-toxic form.
Governments around the world are considering a range of waste management and disposal options, usually involving deep-geologic placement, although there has been limited progress toward implementing long-term waste management solutions. This is partly because the timeframes in question when dealing with radioactive waste range from 10,000 to millions of years, according to studies based on the effect of estimated radiation doses.
Selected image
![](https://upload.wikimedia.org/wikipedia/commons/thumb/a/aa/Polarlicht_2.jpg/340px-Polarlicht_2.jpg)
Photo credit: Senior Airman Joshua Strang, United States Air Force
An aurora, caused by the release of energy as charged particles collide with atoms in the Earth's upper atmosphere.
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
Born in Ireland, Thomson studied at the University of Glasgow, Scotland. On graduating, he became a mathematics teacher at the Royal Belfast Academical Institution. During his life Thomson published more than 600 scientific papers and filed over 70 patents.
As early as 1845 Thomson pointed out that the experimental results of William Snow Harris were in accordance with the laws of Coulomb. Over the period 1855 to 1867, Thomson collaborated with Peter Guthrie Tait the Treatise on Natural Philosophy that unified the various branches of physical science under the common principle of energy. His inventions included the current balance for the precise specification of the ampere, the standard unit of electric current.
In 1893, Thomson headed an international commission to decide on the design of the Niagara Falls power station. Despite his previous belief in the superiority of direct current electric power transmission, he agreed to use alternating current after seeing a Westinghouse demonstration at the Chicago World's Fair.
In the news
- 10 July 2024 – Russian invasion of Ukraine
- Two Ukrainians are killed by Russian drone and missile attacks on a port in southern Odesa Oblast, Ukraine, which damaged port infrastructure, an energy facility, and a civilian ship. (Reuters)
- 22 June 2024 – Russian invasion of Ukraine
- Russia launches missile and drone strikes across Ukraine, injuring two people and damaging energy infrastructure. Ukraine says that it shot down 12 of 16 missiles and all 13 drones. (Reuters)
General images
Quotations
- "In recent years, new nations have entered enthusiastically into industrial production, thereby increasing their energy needs. This has led to an unprecedented race for available resources. Meanwhile, some parts of the planet remain backward and development is effectively blocked, partly because of the rise in energy prices. What will happen to those peoples?" – Pope Benedict XVI, 2007
- "In order to prevent the harmful consequences that crude oil price volatility is having on the well-being of our people, it is urgent that we convene a World Leaders Summit to present alternative solutions to this serious problem, which could quite possibly be a significant shock to the prosperity of developing nations." – Leonel Fernández, 2005
Related portals
WikiProjects
WikiProjects connected with energy:
Other WikiProjects that may be of interest:
Major topics
Major categories
National energy supply, use & conservation
National electricity sector
Politics, economics, environment
- Climate change
- Energy conservation
- Energy economics
- Energy crises
- Energy development
- Energy policy
- Peak oil
Energy sources
- Fuels
- Biofuels
- Fossil fuels
- Fusion power
- Nuclear technology
- Renewable energy
- Energy conversion
- Electric power
- Energy storage
Energy-related design
Scientific usage
Help
![](https://upload.wikimedia.org/wikipedia/commons/thumb/7/72/Torchlight_help_icon.svg/55px-Torchlight_help_icon.svg.png)
Puzzled by energy?
Can't answer your question?
Don't understand the answer?
- Ask at the reference desk
- Read the Wikipedia help pages
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:
-
Commons
Free media repository -
Wikibooks
Free textbooks and manuals -
Wikidata
Free knowledge base -
Wikinews
Free-content news -
Wikiquote
Collection of quotations -
Wikisource
Free-content library -
Wikiversity
Free learning tools -
Wiktionary
Dictionary and thesaurus
-
-
-
-
-
Random portal
Purge server cache
Recent Comments