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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

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

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).

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, the internal energy contained within a thermodynamic system, and rest energy associated with an object's rest mass. These are not mutually exclusive.

All living organisms constantly take in and release energy. The Earth's climate and ecosystems processes are driven primarily by radiant energy from the sun. The energy industry provides the energy required for human civilization to function, which it obtains from energy resources such as fossil fuels, nuclear fuel, and renewable energy. (Full article...)

Selected article

Coal is a readily combustible black or brownish-black rock composed primarily of carbon and formed from plant remains. It is the world's largest single source of fuel for electricity generation, and its fastest growing energy source. It is also the world's largest source of carbon dioxide emissions, one of the key greenhouse gases that are believed to be the primary cause of global warming.

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 Arnold Paul
Coal-fired power stations transform chemical energy into 36%-48% electricity and 52%-64% waste heat.

Did you know?

The Geysers
The Geysers

Selected biography

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Enrico Fermi (September 29, 1901 – November 28, 1954) was an Italian physicist most noted for his work on the development of the first nuclear reactor, and for the development of quantum theory. Fermi won the 1938 Nobel Prize in Physics for his work on induced radioactivity.

Fermi was well-known for his simplicity in solving problems. Whenever possible, he avoided complicated mathematics and obtained quick results based on order of magnitude estimates. Fermi also meticulously recorded his calculations in notebooks, and later used to solve many new problems that he encountered based on these earlier known problems.

After accepting the 1938 Nobel Prize in Stockholm, Fermi immigrated to New York with his family to escape the anti-Semitic laws of Fascist Italy, as his wife Laura was Jewish.

After working at Columbia University, Fermi went to the University of Chicago and began studies that led to the construction of the world's first nuclear reactor Chicago Pile-1 (CP-1). The first artificial, self-sustaining, nuclear chain reaction was initiated within CP-1, on December 2, 1942.

In the news

19 February 2025 – Russian invasion of Ukraine
At least one person is killed and 14 others are injured in Russian missile and drone strikes across Ukraine, including a large drone attack on energy infrastructure in Odesa that leaves 160,000 residents without heating and electricity. (The Kyiv Independent)
18 February 2025 –
Brazilian minister of mines and energy Alexandre Silveira announces that the country will join OPEC+. (AP)
12 February 2025 – Neutrino detection
Researchers at the KM3NeT collaboration, published their results on the highest energy neutrino ever detected. The infrastructure, located at the bottom of the Mediterranean Sea, recorded an event 30 times more energetic than the previous record holder. (Nature), (AP)
9 February 2025 – 2025 Sri Lanka blackouts
A nationwide blackout occurs in Sri Lanka. Energy Minister Kumara Jayakody says a monkey triggered the mass power outage after "coming into contact" with a grid transformer at a substation near Colombo. (BBC News)
6 February 2025 – Moldova–European Union relations
2025 Moldovan energy crisis

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