What are the main forms of energy?
Energy
The total energy of a system can be subdivided and classified into potential energy, kinetic energy, or combinations of the two in various ways. Kinetic energy is determined by the movement of an object – or the composite motion of the components of an object – and potential energy reflects the potential of an object to have motion, and generally is a function of the position of an object within a field or may stored in the field itself.
Eckart conditions
The vibrational energy of the molecule can be written in terms of coordinates with respect to the Eckart frame as
Because the Eckart frame is non-inertial, the total kinetic energy comprises also centrifugal and Coriolis energies. These stay out of the present discussion. The vibrational energy is written in terms of the displacement coordinates, which are linearly dependent because they are contaminated by the 6 external modes, which are zero, i.e., the d's satisfy 6 linear relations. It is possible to write the vibrational energy solely in terms of the internal modes "q" ("r" =1, ..., 3"N"-6) as we will now show. We write the different modes in terms of the displacements
The parenthesized expressions define a matrix B relating the internal and external modes to the displacements. The matrix B may be partitioned in an internal (3"N"-6 x 3"N") and an external (6 x 3"N") part,
We define the matrix M by
and from the relations given in the previous sections follow the matrix relations
and
We define
By using the rules for block matrix multiplication we can show that
where G is of dimension (3"N"-6 x 3"N"-6) and N is (6 x 6).
The kinetic energy becomes
where we used that the last 6 components of v are zero. This form of
the kinetic energy of vibration enters Wilson's GF method. It is of some interest to point out that the potential energy in the harmonic approximation can be written as follows
where H is the Hessian of the potential in the minimum and F, defined by this equation, is the F matrix of the GF method.
Energy principles in structural mechanics
Energy principles in structural mechanics express the relationships between stresses, strains or deformations, displacements, material properties, and external effects in the form of energy or work done by internal and external forces. Since energy is a scalar quantity, these relationships provide convenient and alternative means for formulating the governing equations of deformable bodies in solid mechanics. They can also be used for obtaining approximate solutions of fairly complex systems, bypassing the difficult task of solving the set of governing partial differential equations.
Energy autarkic/autonomic habitats
Life on our planet is a permanent energy flow between living things and the environment. Most of the currently used energy resources, such as oil, coal, natural gas and uranium are non-renewable. The supply of them buried in the earth is limited and we are using them up at a rapid pace.
Renewable energy resources such as Solar energy, wind energy, small hydroelectricity (e.g. Swimming hydroelectric power plant), geothermal energy and biomass fuels are becoming increasingly attractive. Solar, Photovoltaics, water and wind energy do not send pollutants into the air as occurs with coal and petroleum energy.
Energy homeostasis
The first law of thermodynamics states that energy can be neither created nor destroyed. But energy can be converted from one form of energy to another. So, when a calorie of food energy is consumed, one of three particular effects occur within the body: a portion of that calorie may be stored as body fat, triglycerides, or glycogen, transferred to cells and converted to chemical energy in the form of adenosine triphosphate (ATP – a coenzyme) or related compounds, or dissipated as heat.
Energy management
According to Kals there are the following energy strategies:In reality, you usually find hybrid forms of different strategies.
Electricity market
Wholesale transactions (bids and offers) in electricity are typically cleared and settled by the market operator or a special-purpose independent entity charged exclusively with that function. Market operators do not clear trades but often require knowledge of the trade in order to maintain generation and load balance.
The commodities within an electric market generally consist of two types: power and energy. Power is the metered net electrical transfer rate at any given moment and is measured in megawatts (MW). Energy is electricity that flows through a metered point for a given period and is measured in megawatt-hours (MWh).
Energy level
with
Heat transfer physics
Heat transfer physics describes the kinetics of energy storage, transport, and energy transformation by principal energy carriers: phonons (lattice vibration waves), electrons, fluid particles, and photons. Heat is energy stored in temperature-dependent motion of particles including electrons, atomic nuclei, individual atoms, and molecules. Heat is transferred to and from matter by the principal energy carriers. The state of energy stored within matter, or transported by the carriers, is described by a combination of classical and quantum statistical mechanics. The energy is also transformed (converted) among various carriers.
The heat transfer processes (or kinetics) are governed by the rates at which various related physical phenomena occur, such as (for example) the rate of particle collisions in classical mechanics. These various states and kinetics determine the heat transfer, i.e., the net rate of energy storage or transport. Governing these process from the atomic level (atom or molecule length scale) to macroscale are the laws of thermodynamics, including conservation of energy.
Borda–Carnot equation
with
The first three terms, on either side of the equal sign are respectively the pressure, the kinetic energy density of the fluid and the potential energy density due to gravity. As can be seen, pressure acts effectively as a form of potential energy.
Waste heat
In the majority of energy applications, energy is required in multiple forms. These energy forms typically include some combination of: heating, ventilation, and air conditioning, mechanical energy and electric power. Often, these additional forms of energy are produced by a heat engine, running on a source of high-temperature heat. A heat engine can never have perfect efficiency, according to the second law of thermodynamics, therefore a heat engine will always produce a surplus of low-temperature heat. This is commonly referred to as waste heat or "secondary heat", or "low-grade heat". This heat is useful for the majority of heating applications, however, it is sometimes not practical to transport heat energy over long distances, unlike electricity or fuel energy.
The largest proportions of total waste heat are from power stations and vehicle engines. The largest single sources are power stations and industrial plants such as oil refineries and steelmaking plants.
Bioenergetic systems
Bioenergetic systems are metabolic processes that relate to the flow of energy in living organisms. Those processes convert energy into adenosine triphosphate (ATP), which is the form suitable for muscular activity. There are two main forms of synthesis of ATP: "aerobic", which involves oxygen from the bloodstream, and "anaerobic", which does not. Bioenergetics is the field of biology that studies bioenergetic systems.
Climate Consortium Denmark
On the supply side energy sources have been heavily diversified and now include: wind power (20% of electricity as of 2009); bio-mass including second generation bio-ethanol; gas from the North Sea and the Continent; the most energy-efficient coal fuelled combined heating power plants in the world; and ordinary gasoline fuel mainly used in transportation.
Primary energy
Primary energy sources are transformed in energy conversion processes to more convenient forms of energy that can directly be used by society, such as electrical energy, refined fuels, or synthetic fuels such as hydrogen fuel. In the field of energetics, these forms are called energy carriers and correspond to the concept of "secondary energy" in energy statistics.
Energy–depth relationship in a rectangular channel
With the pressure term neglected, energy exists in two forms, potential and kinetic. Assuming all the fluid particles are moving at the same velocity, the general expression for kinetic energy applies (KE = ½mv). This general expression can be written in terms of kinetic energy per unit weight of fluid,
Energy density
The highest density sources of energy aside from antimatter are fusion and fission. Fusion includes energy from the sun which will be available for billions of years (in the form of sunlight) but so far (2018), sustained fusion power production continues to be elusive.
Electric power
Electric power is transformed to other forms of energy when electric charges move through an electric potential (voltage) difference, which occurs in electrical components in electric circuits. From the standpoint of electric power, components in an electric circuit can be divided into two categories: 
Some devices can be either a source or a load, depending on the voltage and current through them. For example, a rechargeable battery acts as a source when it provides power to a circuit, but as a load when it is connected to a battery charger and is being recharged, or a generator as a power source and a motor as a load.
Energetic material
Typical classes of energetic materials are e.g. explosives, pyrotechnic compositions, propellants (e.g. smokeless gunpowders and rocket fuels), and fuels (e.g. diesel fuel and gasoline).
Radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes:
Lists of renewable energy topics
Renewable energy is generally defined as energy that comes from resources which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy replaces conventional fuels in four distinct areas: electricity generation, air and water heating/cooling, motor fuels, and rural (off-grid) energy services. Based on REN21's 2014 report, renewables contributed 19 percent to our global energy consumption and 22 percent to our electricity generation in 2012 and 2013, respectively.
Energy storage
The following list includes a variety of types of energy storage:Energy can be stored in water pumped to a higher elevation using pumped storage methods or by moving solid matter to higher locations (gravity batteries). 
Other commercial mechanical methods include compressing air and flywheels that convert electric energy into kinetic energy and then back again when electrical demand peaks.
Transparency and translucency
The primary physical mechanism for storing mechanical energy of motion in condensed matter is through heat, or thermal energy. Thermal energy manifests itself as energy of motion. Thus, heat is motion at the atomic and molecular levels. The primary mode of motion in crystalline substances is vibration. Any given atom will vibrate around some mean or average position within a crystalline structure, surrounded by its nearest neighbors. This vibration in two dimensions is equivalent to the oscillation of a clock’s pendulum. It swings back and forth symmetrically about some mean or average (vertical) position. Atomic and molecular vibrational frequencies may average on the order of 10 cycles per second (Terahertz radiation).
Physiology of marathons
Humans metabolize food to synthesize energy in the form of Adenosine triphosphate (ATP). This is the human body's instant accessible form of energy for all functions of cells within the body. For exercise the human body places high demand for ATP to supply its self with enough energy to support all the corresponding changes in the body at work. The 3 energy systems involved in exercise are the Phosphogenic, Anaerobic and Aerobic energy pathways. The simultaneous action of these three energy pathways prioritizes one specific pathway over the others depending on the type of exercise an individual is partaking in. This differential prioritization is based on the duration and intensity of the particular exercise being performed. The variable usage of these energy pathways is central to the mechanisms that allow for long, sustained exercise, such as a marathon running, to be maintained.
Vitalism
Such a field is sometimes explained as electromagnetic, though some advocates also make confused appeals to quantum physics. Joanne Stefanatos states that "The principles of energy medicine originate in quantum physics." Stenger offers several explanations as to why this line of reasoning may be misplaced. He explains that energy exists in discrete packets called quanta. Energy fields are composed of their component parts and so only exist when quanta are present. Therefore, energy fields are not holistic, but are rather a system of discrete parts that must obey the laws of physics. This also means that energy fields are not instantaneous. These facts of quantum physics place limitations on the infinite, continuous field that is used by some theorists to describe so-called "human energy fields". Stenger continues, explaining that the effects of EM forces have been measured by physicists as accurately as one part in a billion and there is yet to be any evidence that living organisms emit a unique field.
Ecometrics
Energy is used up and lost as heat as it moves through ecosystems, and new energy is continually added to the earth in the form of solar radiation. The earth is an open system in regards to energy, it is constantly accepting it in the form of solar radiation. Nutrients and other materials at large however are continuously circulated within and among ecosystems. The primary organism within any food system is capable of utilizing energy to synthesize organic compounds from inorganic precursors, and of storing biochemical energy in the process. The growth of the plant is primary production, this results in the increase of plant biomass to a system. Primary consumers get their energy from primary producers, and thus are able to assimilate the producer’s stored energy. As a generalized trophic level consumers feed on all forms of organisms, and more specifically there are types of consumers by instinct or choice(herbivores, vegetarians, omnivores). 
Beyond the initial consumer there may be other consumers who derive their energy from consumers preceding them. Primary production provides for all trophic members as it provides energy to primary consumers that in turn provide energy to secondary consumers and so forth. In this way energy is transferred from one form and source to another. The efficiency for consumers to grow is limited by the use of their feed for a metabolic processes and their efficiency of conversion for digested food. The energy that is used for growth is assimilated into new tissue or reproduction and is the net production stored as a result for this process. On average metabolic processes utilize 90% of the gross energy intake, whereas assimilation utilizes 10%. The amount that is assimilated out of all the total energy intake is also the efficiency of conversion. The collective energy assimilated in one trophic level is the energy available to the succeeding level. There is consecutively less energy available to succeeding trophic levels. 
Consider a situation where 1000k calories are available to beef through grain feed and that their net production after consuming feed is 100k calories, only 100k calories would be available to the trophic level above, and beyond that 10k calories for the next.
Sustainable energy
Anaerobic digestion, geothermal power, wind power, small-scale hydropower, solar energy, biomass power, tidal power, wave power, and some forms of nuclear power (ones which are able to "burn" nuclear waste through a process known as nuclear transmutation, such as an Integral Fast Reactor, and therefore belong in the "Green Energy" category). Some definitions may also include power derived from the incineration of waste.
Outline of solar energy
Solar energy – radiant light and heat from the sun. It has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar energy technologies include solar heating, solar photovoltaics, solar thermal electricity and solar architecture, which can make considerable contributions to solving some of the most urgent problems the world now faces.
Solar energy can be described as all of the following:
Solar power – the conversion of sunlight into electricity, either directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP).
Omega Point
Energy exists in two basic modes:
Energetics
As a general statement of energy flows under transformation, the principles of energetics include the first four laws of thermodynamics which seek a rigorous description. However the precise place of the laws of thermodynamics within the principles of energetics is a topic currently under debate. If the ecologist Howard T. Odum was right, the principles of energetics take into consideration a hierarchical ordering of energy forms, which aims to account for the concept of energy quality, and the evolution of the universe. Albert Lehninger (1973, p. 2) called these hierarchical orderings the
Potential energy
An object can have potential energy by virtue of its electric charge and several forces related to their presence. There are two main types of this kind of potential energy: electrostatic potential energy, electrodynamic potential energy (also sometimes called magnetic potential energy).
Pulsed power
Energy is typically stored within electrostatic fields (capacitors), magnetic fields (inductor), as mechanical energy (using large flywheels connected to special purpose high current alternators), or as chemical energy (high-current lead-acid batteries, or explosives). By releasing the stored energy over a very short interval (a process that is called energy compression), a huge amount of peak power can be delivered to a load. For example, if one joule of energy is stored within a capacitor and then evenly released to a load over one second, the average power delivered to the load would only be 1 watt. However, if all of the stored energy were released within one microsecond, the average power over one second would still be one watt, but the instantaneous peak power would be one megawatt, a million times greater. Examples where pulsed power technology is commonly used include radar, particle accelerators, ultrastrong magnetic fields, fusion research, electromagnetic pulses, and high power pulsed lasers.
Energy
Energy may be transformed between different forms at various efficiencies. Items that transform between these forms are called transducers. Examples of transducers include a battery, from chemical energy to electric energy; a dam: gravitational potential energy to kinetic energy of moving water (and the blades of a turbine) and ultimately to electric energy through an electric generator; or a heat engine, from heat to work.
Energy development
Renewable energy is generally defined as energy that comes from resources which are naturally replenished on a human timescale such as sunlight, wind, rain, tides, waves and geothermal heat. Renewable energy replaces conventional fuels in four distinct areas: electricity generation, hot water/space heating, motor fuels, and rural (off-grid) energy services.
Energy in Ethiopia
The three main energy carriers in Ethiopia are refined oil products (diesel, gasoline, kerosene), electricity (from solar radiation, water, wind, heat) and bioethanol (from sugarcane). Bioethanol wasn't produced in substantial quantities until very recently, it makes up 0.4 TWh annually (2017). Electricity is about to replace diesel as the main energy carrier in Ethiopia – but taken all refined oil products altogether (38.5 TWh in 2014), electricity (22.5 TWh in 2016) will still take a few years before it will surpass oil products as main energy carrier. Both the amount of imported refined oil products and the produced electricity are increasing – but the growth rate for electricity is much higher than that for refined oil products. See the table. For a developing country it is usually the other way round.
Renewable energy in Mexico
The main forms of renewable energy used in Mexico are hydropower, biomass, geothermal, solar power and wind. While all of these are assisting in lowering the fossil fuel count and carbon emissions.
Energy density
Power from fission of uranium and thorium in nuclear power plants will be available for many decades or even centuries because of the plentiful supply of the elements on earth, though the full potential of this source can only be realised through breeder reactors, which are, apart from the BN-600 reactor, not yet used commercially. Coal, gas, and petroleum are the current primary energy sources in the U.S. but have a much lower energy density. Burning local biomass fuels supplies household energy needs (cooking fires, oil lamps, etc.) worldwide.
List of books about renewable energy
Renewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are renewable (naturally replenished). About 16% of global final energy consumption comes from renewables, with 10% coming from traditional biomass, which is mainly used for heating, and 3.4% from hydroelectricity. New renewables (small hydro, modern biomass, wind, solar, geothermal, and biofuels) account for another 3% and are growing very rapidly.
Energy transformation
Energy transformations in the universe over time are (generally) characterized by various kinds of energy which have been available since the Big Bang, later being "released" (that is, transformed to more active types of energy such as kinetic or radiant energy), when a triggering mechanism is available to do it.
Energy transformation
Thus, according to present understanding, familiar events such as landslides and earthquakes release energy which has been stored as potential energy in the Earth's gravitational field, or elastic strain (mechanical potential energy) in rocks. Prior to this, the energy represented by these events had been stored in heavy atoms (or in the gravitational potential of the Earth). The energy stored in heat atoms had been stored as potential ever since the time that gravitational potentials transforming energy in the collapse of long-destroyed stars (supernovae) created these atoms, and in doing so, stored the energy within.
Energy
This equation is highly specific, ignoring all chemical, electrical, nuclear, and gravitational forces, effects such as advection of any form of energy other than heat and pV-work. The general formulation of the first law (i.e., conservation of energy) is valid even in situations in which the system is not homogeneous. For these cases the change in internal energy of a "closed" system is expressed in a general form by
Energy in Africa
According to Stephen Karekezi, Director of African Energy Policy Research Network and co-worker Waeni Kithyoma, Africa is third largest in crude oil reserves (behind the Middle East and Latin America), third largest in natural gas resources (behind the Middle East and Europe), second greatest for uranium (behind Australia), and is plentiful in hydro energy potentials and other renewable energy, such as bio-energy and solar energy. Professor Iwayemi states that there are conventional energy sources in Africa: hydroelectric and wood fuels, coal lignite, crude oil, natural gas and nuclear fuels, and there are unconventional energy sources, such as solar, geothermal, biomass, oil and tar sands, wind energy and tidal energy from the influence of the sea.
Potentiality and actuality
There was an adaptation of at least one aspect of Aristotle's potentiality and actuality distinction, which has become part of modern physics, although as per Bacon's approach it is a generalized form of energy, not one connected to specific forms for specific things. The definition of energy in modern physics as the product of mass and the square of velocity, was derived by Leibniz, as a correction of Descartes, based upon Galileo's investigation of falling bodies. He preferred to refer to it as an "entelecheia" or "living force" (Latin "vis viva"), but what he defined is today called "kinetic energy", and was seen by Leibniz as a modification of Aristotle's "energeia", and his concept of the potential for movement which is in things. Instead of each type of physical thing having its own specific tendency to a way of moving or changing, as in Aristotle, Leibniz said that instead, force, power, or motion itself could be transferred between things of different types, in such a way that there is a general conservation of this energy. In other words, Leibniz's modern version of entelechy or energy obeys its own laws of nature, whereas different types of things do not have their own separate laws of nature. Leibniz wrote: ...the entelechy of Aristotle, which has made so much noise, is nothing else but force or activity ; that is, a state from which action naturally flows if nothing hinders it. But matter, primary and pure, taken without the souls or lives which are united to it, is purely passive ; properly speaking also it is not a substance, but something incomplete.
Primary energy
Source energy, in contrast, is the term used in North America for the amount of primary energy consumed in order to provide a facility’s site energy. It is always greater than the site energy, as it includes all site energy and adds to it the energy lost during transmission, delivery, and conversion. While source or primary energy provides a more complete picture of energy consumption, it cannot be measured directly and must be calculated using conversion factors from site energy measurements. For electricity, a typical value is three units of source energy for one unit of site energy. However, this can vary considerably depending on factors such as the primary energy source or fuel type, the type of power plant, and the transmission infrastructure. One full set of conversion factors is available as technical reference from Energy STAR.
Conservation of energy
Matter is composed of such things as atoms, electrons, neutrons, and protons. It has "intrinsic" or "rest" mass. In the limited range of recognized experience of the nineteenth century it was found that such rest mass is conserved. Einstein's 1905 theory of special relativity showed that it corresponds to an equivalent amount of "rest energy". This means that it can be converted to or from equivalent amounts of "other" (non-material) forms of energy, for example kinetic energy, potential energy, and electromagnetic radiant energy. When this happens, as recognized in twentieth century experience, rest mass is not conserved, unlike the "total" mass or "total" energy. All forms of energy contribute to the total mass and total energy.
Nigerian energy supply crisis
Currently Nigeria uses four different types of energy: natural gas, oil, hydro and coal The energy sector is heavily dependent on petroleum as a method for electricity production which has slowed down the development of alternative forms of energy. Three out of the four above resources used for energy production in Nigeria are linked with increasing greenhouse gas emissions: coal, oil and natural gas, with coal emitting the worst of the three.
List of largest power stations
This article lists the largest power stations in the world, the ten overall and the five of each type, in terms of current installed electrical capacity. Non-renewable power stations are those that run on coal, fuel oils, nuclear, natural gas, oil shale and peat, while renewable power stations run on fuel sources such as biomass, geothermal heat, hydro, solar energy, solar heat, tides, waves and the wind. Only the most significant fuel source is listed for power stations that run on multiple sources.
Energy transformation
Energy transformation, also termed energy conversion, is the process of changing energy from one of its forms into another. In physics, energy is a quantity that provides the capacity to perform work — think of lifting or warming an object. In addition to being convertible,and also according to the law of conservation of energy, energy is transferable to a different location or object, but it cannot be created or destroyed.
Biogeochemical cycle
The flow of energy in an ecosystem is an "open system"; the sun constantly gives the planet energy in the form of light while it is eventually used and lost in the form of heat throughout the trophic levels of a food web. Carbon is used to make carbohydrates, fats, and proteins, the major sources of food energy. These compounds are oxidized to release carbon dioxide, which can be captured by plants to make organic compounds. The chemical reaction is powered by the light energy of the sun.
Worldwide energy supply
Primary energy assessment follows certain rules to ease measurement and comparison of different kinds of energy. Due to these rules uranium is not counted as PE but as the natural source of nuclear PE. Similarly water and air flow energy that drives hydro and wind turbines, and sunlight that powers solar panels, are not taken as PE but as PE sources.
Energy returned on energy invested
Another issue with EROI that many studies attempt to tackle is that the energy returned can be in different forms, and these forms can have different utility. For example, electricity can be converted more efficiently than thermal energy into motion, due to electricity's lower entropy. In addition, the form of energy of the input can be completely different from the output. For example, energy in the form of coal could be used in the production of ethanol. This might have an EROEI of less than one, but could still be desirable due to the benefits of liquid fuels (assuming the latters are not used in the processes of extraction and transformation).
Energy carrier
Such carriers include springs, electrical batteries, capacitors, pressurized air, dammed water, hydrogen, petroleum, coal, wood, and natural gas. An energy carrier does not produce energy; it simply contains energy imbued by another system.
Elemental (Dungeons &amp; Dragons)
Types of quasi-elementals deriving from elements infused with positive energy include lightning (air), mineral (earth), radiance (fire), and steam (water). Types of quasi-elementals deriving from elements infused with negative energy include ash (fire), dust (earth), salt (water), and vacuum (air).
Energy quality
Energy quality is the contrast between different forms of energy, the different trophic levels in ecological systems and the propensity of energy to convert from one form to another. The concept refers to the empirical experience of the characteristics, or qualia, of different energy forms as they flow and transform. It appeals to our common perception of the heat value, versatility, and environmental performance of different energy forms and the way a small increment in energy flow can sometimes produce a large transformation effect on both energy physical state and energy. For example the transition from a solid state to liquid may only involve a very small addition of energy. Methods of evaluating energy quality are sometimes concerned with developing a system of ranking energy qualities in hierarchical order.
Haegemonia: Legions of Iron
Energy weapons are split up into three groups: cannons (fighters only), turrets (anti-fighter, used on turret corvettes and heavy ships), and blasters (only energy weapon for orbital bombardment, used on blaster corvettes and heavy ships). Contrary to popular belief, ships equipped with turrets can bombard planets, just not as effectively. Weaponry also comes in four distinct forms:
Energy
In cosmology and astronomy the phenomena of stars, nova, supernova, quasars and gamma-ray bursts are the universe's highest-output energy transformations of matter. All stellar phenomena (including solar activity) are driven by various kinds of energy transformations. Energy in such transformations is either from gravitational collapse of matter (usually molecular hydrogen) into various classes of astronomical objects (stars, black holes, etc.), or from nuclear fusion (of lighter elements, primarily hydrogen). The nuclear fusion of hydrogen in the Sun also releases another store of potential energy which was created at the time of the Big Bang. At that time, according to theory, space expanded and the universe cooled too rapidly for hydrogen to completely fuse into heavier elements. This meant that hydrogen represents a store of potential energy that can be released by fusion. Such a fusion process is triggered by heat and pressure generated from gravitational collapse of hydrogen clouds when they produce stars, and some of the fusion energy is then transformed into sunlight.
Passive sign convention
In electrical engineering, power represents the rate of electrical energy flowing into or out of a given component or control volume. Power is a signed quantity; negative power just represents power flowing in the opposite direction from positive power. From the standpoint of power flow, electrical components in a circuit can be divided into two types: 
Some components can be either a source or a load, depending on the voltage or current through them. For example, a rechargeable battery acts as a source when it is used to produce power, but as a load when it is being recharged.
Hydrocarbon
Hydrocarbons are currently the main source of the world's electric energy and heat sources (such as home heating) because of the energy produced when burnt. Often this energy is used directly as heat such as in home heaters, which use either petroleum or natural gas. The hydrocarbon is burnt and the heat is used to heat water, which is then circulated. A similar principle is used to create electric energy in power plants.
Outline of energy
Energy – in physics, this is an indirectly observed quantity often understood as the ability of a physical system to do work on other physical systems. Since work is defined as a force acting through a distance (a length of space), energy is always equivalent to the ability to exert force (a pull or a push) against an object that is moving along a definite path of certain length.Units of energyEnergy industry
Worldwide energy supply
Primary energy is converted in many ways to energy carriers, also known as secondary energy.
Conservation form
Each of these represents the conservation of mass, momentum and energy, respectively.
Powershift (book)
The combination of knowledge, wealth and force is described by Toffler as providing individuals or other entities power. Knowledge is the most powerful form of power, considering we are now living in a Knowledge-based civilization. Wealth is another form of power, and is flexible in nature, since it can be used as punishment (like a stick) or reward (as a carrot). Finally force, in lay terms violence, is noted as another element of power. It isn't as flexible as the other elements of power, since you can't exactly "take back" shooting someone or punching them in the face. However, the psychological capability that you have force available, like a cowboy or police man with a gun his holster is often all it takes to ensure compliance.
Energy quality
Ohta sought to order energy form conversions according to their quality and introduced a hierarchical scale for ranking energy quality based on the relative ease of energy conversion (see table to right after Ohta, p. 90). It is evident that Ohta did not analyse all forms of energy. For example, water is left out of his evaluation. It is important to note that the ranking of energy quality is not determined solely with reference to the efficiency of the energy conversion. This is to say that the evaluation of "relative ease" of an energy conversion is only partly dependent on transformation efficiency. As Ohta wrote, "the turbine generator and the electric motor have nearly the same efficiency, therefore we cannot say which has the higher quality" (1994, p. 90). Ohta therefore also included, 'abundance in nature' as another criterion for the determination energy quality rank. For example, Ohta said that, "the only electrical energy which exists in natural circumstances is lightning, while many mechanical energies exist." (Ibid.). (See also table 1. in Wall's article for another example ranking of energy quality).
Energy being
An energy being or astral being is a theoretical life form that is composed of energy rather than matter. They appear in myths/legends, paranormal/UFO accounts, and in various works of speculative fiction.
Energy
While these two categories are sufficient to describe all forms of energy, it is often convenient to refer to particular combinations of potential and kinetic energy as its own form. For example, macroscopic mechanical energy is the sum of translational and rotational kinetic and potential energy in a system neglects the kinetic energy due to temperature, and nuclear energy which combines utilize potentials from the nuclear force and the weak force), among others.
Primary energy
Primary energy (PE) is an energy form found in nature that has not been subjected to any human engineered conversion process. It is energy contained in raw fuels, and other forms of energy received as input to a system. Primary energy can be non-renewable or renewable.
Energy Observer
Energy Observer is a floating laboratory, destined to test an innovative energy architecture in extreme conditions, to prove its feasibility onshore. The energy system encompasses 3 renewable energy sources (sun, wind and hydropower) and two types of storage (li-ion batteries for the short-term and hydrogen for the long-term). The ship can produce hydrogen directly onboard, through seawater electrolysis. The goal is to test and optimize these technological bricks, in order to have them working in harmony, and aim toward total energy autonomy. Each year, the vessel will go back to the shipyard to analyze the navigation and the evolution of the embarked technologies.
Small power
Small states’ power can be categorized as "particular-intrinsic", “"derivative"” and "collective". Through one of these three types of power can small states best seek their needs and interest. Middle or great powers are not precluded from these types of power, only the limitations of the small states force them to rely on them more. Small states have different goals and different bases, i.e. ideational, material and relational bases. Bases are the resources that a state has and can exploit in order to effect another’s behavior. This variation of small states’ bases lead to a variety of means of power. Means in this context are the ways a state utilizes its base. The three categories of power all have different bases and therefore different means, best understood as small states’ properties and its actions.
Fossil fuel phase-out
Renewable energy is energy that comes from resources which are naturally replenished such as sunlight, wind, rain, tides, waves, and geothermal heat. , 19% of global final energy consumption comes from renewable resources, with 9% of all energy from traditional biomass, mainly used for heating, 1% from biofuels, 4% from hydroelectricity and 4% from biomass, geothermal or solar heat. Popular renewables (wind, solar, geothermal and biomass for power) accounted for another 1.4% and are growing rapidly. While renewable energy supplies are growing and have displaced coal in some regions, the amount of coal burned in 2021, is expected to be the same as it was in 2014.
Emergy
Emergy is the amount of energy that was consumed in direct and indirect transformations to make a product or service. Emergy is a measure of quality differences between different forms of energy. Emergy is an expression of all the energy used in the work processes that generate a product or service in units of one type of energy. Emergy is measured in units of "emjoule"s, a unit referring to the available energy consumed in transformations. Emergy accounts for different forms of energy and resources (e.g. sunlight, water, fossil fuels, minerals, etc.) Each form is generated by transformation processes in nature and each has a different ability to support work in natural and in human systems. The recognition of these quality differences is a key concept.
Universal Medicine
Serge Benhayon devised Universal Medicine's healing practices based on the belief that disease is caused by energetic disharmony resulting from ill choices made in this and previous lifetimes. Benhayon teaches that there are two types of energy: prana (, ; Sanskrit for life force) and fire. Most forms of established wisdom, knowledge and belief, as well as most music and certain foods are believed to contain prana, which he regards as evil. Prana is to be rejected or cleared to be replaced with "fiery energy" which emanates from the "Atmic womb of God". Universal Medicine healing modalities and products, including teas, herbal elixirs, creams and laminated healing symbol postcards, aim to clear prana.
World energy consumption
Closely related to energy consumption is the concept of total primary energy supply (TPES), which - on a global level - is the sum of energy production minus storage changes. Since changes of energy storage over the year are minor, TPES values can be used as an estimator for energy consumption. However, TPES ignores conversion efficiency, overstating forms of energy with poor conversion efficiency (e.g. coal, gas and nuclear) and understating forms already accounted for in converted forms (e.g. photovoltaic or hydroelectricity). The IEA estimates that, in 2013, total primary energy supply (TPES) was 1.575 × 10 Wh (= 157.5 PWh, 157,500 TWh, 5.67 × 10 joules, or 13,541 Mtoe) or about 18 TW-year. From 2000–2012 coal was the source of energy with the largest growth. The use of oil and natural gas also had considerable growth, followed by hydropower and renewable energy. Renewable energy grew at a rate faster than any other time in history during this period. The demand for nuclear energy decreased, in part due to nuclear disasters (e.g. Three Mile Island 1979, Chernobyl 1986, and Fukushima 2011).
Energy storage
Power to gas is a technology which converts electricity into a gaseous fuel such as hydrogen or methane. The three commercial methods use electricity to reduce water into hydrogen and oxygen by means of electrolysis.
Energy development
Societies use energy for transportation, manufacturing, illumination, heating and air conditioning, and communication, for industrial, commercial, and domestic purposes. Energy resources may be classified as primary resources, where the resource can be used in substantially its original form, or as secondary resources, where the energy source must be converted into a more conveniently usable form. Non-renewable resources are significantly depleted by human use, whereas renewable resources are produced by ongoing processes that can sustain indefinite human exploitation.
Blade element momentum theory
Bernoulli's equation describes the different forms of energy that are present in fluid flow where the net energy is constant i.e. when a fluid is not transferring any energy to some other entity such as a rotor. The energy consists of static pressure, gravitational potential energy, and kinetic energy. Mathematically, we have the following expression:
Energy bar
Energy in food comes from three sources: fat, protein, and carbohydrates. A typical energy bar weighs between 45 and 80 g and is likely to supply about 200–300 Cal (840–1,300 kJ), 3–9 g of fat, 7–15 g of protein, and 20–40 g of carbohydrates.
In order to provide energy quickly, most of the carbohydrates are various types of sugars like fructose, glucose, maltodextrin and others in various ratios, combined with complex carbohydrate sources like oats and barley. Proteins come mostly in the form of fast digesting whey protein. Energy bars generally don't contain sugar alcohols, since these bars, due to type of carbohydrate content, don't require low calorie sweeteners to improve their taste. Fats in energy bars are kept to minimum and their main sources are often cocoa butter and dark chocolate.
Primary energy
The concept of primary energy is used in energy statistics in the compilation of energy balances, as well as in the field of energetics. In energetics, a primary energy source (PES) refers to the energy forms required by the energy sector to generate the supply of energy carriers used by human society.
Energy transformation
Energy in many of its forms may be used in natural processes, or to provide some service to society such as heating, refrigeration, lighting or performing mechanical work to operate machines. For example, in order to heat your home, your furnace can burn fuel, whose chemical potential energy is thus converted into thermal energy, which is then transferred to your home's air in order to raise its temperature.
Energy development
Fossil fuel ("primary non-renewable fossil") sources burn coal or hydrocarbon fuels, which are the remains of the decomposition of plants and animals. There are three main types of fossil fuels: coal, petroleum, and natural gas. Another fossil fuel, liquefied petroleum gas (LPG), is principally derived from the production of natural gas. Heat from burning fossil fuel is used either directly for space heating and process heating, or converted to mechanical energy for vehicles, industrial processes, or electrical power generation. These fossil fuels are part of the carbon cycle and thus allow stored solar energy to be used today.
Heat transfer physics
Fluid particle is the smallest unit (atoms or molecules) in the fluid phase (gas, liquid or plasma) without breaking any chemical bond. Energy of fluid particle is divided into potential, electronic, translational, vibrational, and rotational energies. The heat (thermal) energy storage in fluid particle is through the temperature-dependent particle motion (translational, vibrational, and rotational energies). The electronic energy is included only if temperature is high enough to ionize or dissociate the fluid particles or to include other electronic transitions. These quantum energy states of the fluid particles are found using their respective quantum Hamiltonian. These are H"" = -("ħ"/2"m")∇, H"" = -("ħ"/2"m")∇ + Γ"x"/2 and H"" = -("ħ"/2"I")∇ for translational, vibrational and rotational modes. (Γ: spring constant, "I": the moment of inertia for the molecule). From the Hamiltonian, the quantized fluid particle energy state "E" and partition functions "Z" [with the Maxwell–Boltzmann (MB) occupancy distribution] are found as
Robert L. Moore
According to Moore and Gillette, for each optimal orientation for each of these four key sources of energy, there are two corresponding "shadow" forms of the source of the energy—two ways for each of them to be misdirected for only one healthy or optimal way for each of them to be oriented. Just as the authors have given four key sources of energy in the human psyche very colorful names that seem to personify each source, so too the authors give each of the bipolar "shadow" forms very colorful names that seem to personify them.
Chemical substance
Forms of energy, such as light and heat, are not matter, and are thus not "substances" in this regard.
Energy level
Roughly speaking, a molecular energy state, i.e. an eigenstate of the molecular Hamiltonian, is the sum of the electronic, vibrational, rotational, nuclear, and translational components, such that:
Energy being
Energy beings are typically rendered as a translucent glowing fluid or as a collection of flames or electrical sparks or bolts; somewhat in common with the representations of ghosts.
Energy quality
There appear to be two main kinds of methodology used for the calculation of energy quality. These can be classed as either receiver or donor methods. One of the main differences that distinguishes these classes is the assumption of whether energy quality can be upgraded in an energy transformation process.
Self-energy
In most theoretical physics such as quantum field theory, the energy that a particle has as a result of changes that it itself causes in its environment defines self-energy formula_1, and represents the contribution to the particle's energy, or effective mass, due to interactions between the particle and its system. In electrostatics, the energy required to assemble the charge distribution takes the form of self-energy by bringing in the constituent charges from infinity, where the electric force goes to zero. In a condensed matter context relevant to electrons moving in a material, the self-energy represents the potential felt by the electron due to the surrounding medium's interactions with it. Since electrons repel each other the moving electron polarizes, or causes to displace, the electrons in its vicinity and then changes the potential of the moving electron fields. These and other effects entail self-energy.
Marine energy
The energy from moving masses of water — a popular form of hydroelectric power generation. Tidal power generation comprises three main forms, namely: tidal stream power, tidal barrage power, and dynamic tidal power.
Energy storage
Energy storage is the capture of energy produced at one time for use at a later time. 
A device that stores energy is generally called an accumulator or battery. 
Energy comes in multiple forms including radiation, chemical, gravitational potential, electrical potential, electricity, elevated temperature, latent heat and kinetic.
Energy storage involves converting energy from forms that are difficult to store to more conveniently or economically storable forms.
Energy
Energy transformations in the universe over time are characterized by various kinds of potential energy that has been available since the Big Bang later being "released" (transformed to more active types of energy such as kinetic or radiant energy) when a triggering mechanism is available. Familiar examples of such processes include nuclear decay, in which energy is released that was originally "stored" in heavy isotopes (such as uranium and thorium), by nucleosynthesis, a process ultimately using the gravitational potential energy released from the gravitational collapse of supernovae, to store energy in the creation of these heavy elements before they were incorporated into the solar system and the Earth. This energy is triggered and released in nuclear fission bombs or in civil nuclear power generation. Similarly, in the case of a chemical explosion, chemical potential energy is transformed to kinetic energy and thermal energy in a very short time. Yet another example is that of a pendulum. At its highest points the kinetic energy is zero and the gravitational potential energy is at maximum. At its lowest point the kinetic energy is at maximum and is equal to the decrease of potential energy. If one (unrealistically) assumes that there is no friction or other losses, the conversion of energy between these processes would be perfect, and the pendulum would continue swinging forever.
Fuel
It was estimated by the Energy Information Administration that in 2007 primary sources of energy consisted of petroleum 36.0%, coal 27.4%, natural gas 23.0%, amounting to an 86.4% share for fossil fuels in primary energy consumption in the world. Non-fossil sources in 2006 included hydroelectric 6.3%, nuclear 8.5%, and others (geothermal, solar, tidal, wind, wood, waste) amounting to 0.9%. World energy consumption was growing about 2.3% per year.
Adenosine diphosphate
ADP cycling supplies the energy needed to do work in a biological system, the thermodynamic process of transferring energy from one source to another. There are two types of energy: potential energy and kinetic energy. Potential energy can be thought of as stored energy, or usable energy that is available to do work. Kinetic energy is the energy of an object as a result of its motion. The significance of ATP is in its ability to store potential energy within the phosphate bonds. The energy stored between these bonds can then be transferred to do work. For example, the transfer of energy from ATP to the protein myosin causes a conformational change when connecting to actin during muscle contraction. It takes multiple reactions between myosin and actin to effectively produce one muscle contraction, and, therefore, the availability of large amounts of ATP is required to produce each muscle contraction. For this reason, biological processes have evolved to produce efficient ways to replenishment the potential energy of ATP from ADP. 
Breaking one of ATP's phosphorus bonds generates approximately 30.5 kilojoules per Mole of ATP (7.3 kcal). ADP can be converted, or powered back to ATP through the process of releasing the chemical energy available in food; in humans, this is constantly performed via aerobic respiration in the mitochondria. Plants use photosynthetic pathways to convert and store energy from sunlight, also conversion of ADP to ATP. Animals use the energy released in the breakdown of glucose and other molecules to convert ADP to ATP, which can then be used to fuel necessary growth and cell maintenance.
Power (social and political)
JK Galbraith summarizes the types of power as being "condign" (based on force), "compensatory" (through the use of various resources) or "conditioned" (the result of persuasion), and their sources as "personality" (individuals), "property" (their material resources) and "organizational" (whoever sits at the top of an organisational power structure).
Electricity generation
Almost all commercial electrical power on Earth is generated with a turbine, driven by wind, water, steam or burning gas. The turbine drives a generator, thus transforming its mechanical energy into electrical energy by electromagnetic induction. There are many different methods of developing mechanical energy, including heat engines, hydro, wind and tidal power. Most electric generation is driven by heat engines. The combustion of fossil fuels supplies most of the energy to these engines, with a significant fraction from nuclear fission and some from renewable sources. The modern steam turbine (invented by Sir Charles Parsons in 1884) currently generates about 80% of the electric power in the world using a variety of heat sources. Turbine types include:
Although turbines are most common in commercial power generation, smaller generators can be powered by gasoline or diesel engines. These may used for back up generation or isolated villages.
Cubic mile of oil
Significant sources of energy include oil, coal, natural gas, nuclear, hydroelectric, and biomass (primarily the burning of wood). Other energy sources include geothermal, wind, photovoltaic, and solar thermal. The various energy units commonly used to measure these sources (e.g., joules, BTUs, kilowatt hours, therms) are only somewhat familiar to the general public, and their relationships can be confusing. These common energy units are sized for everyday activities (a joule is the energy required to lift a small apple one metre vertically). For regional, national, and global scales, larger energy units, such as the exajoule, the billion barrels of oil equivalent (BBOE) and the quad are used. Derived by multiplying the small common units by large powers of ten these larger units pose additional conceptual difficulties for many citizens.
Anaerobic exercise
The two types of anaerobic energy systems are: 1) high energy phosphates, adenosine triphosphate and creatine phosphate; and 2) anaerobic glycolysis. The former is called "alactic anaerobic" and the latter "lactic anaerobic" system. High energy phosphates are stored in limited quantities within muscle cells. Anaerobic glycolysis exclusively uses glucose (and glycogen) as a fuel in the absence of oxygen, or more specifically when ATP is needed at rates that exceed those provided by aerobic metabolism. The consequence of such rapid glucose breakdown is the formation of lactic acid (or more appropriately, its conjugate base lactate at biological pH levels). Physical activities that last up to about thirty seconds rely primarily on the former, . Beyond this time both aerobic and anaerobic glycolysis-based metabolic systems begin to predominate.
List of energy resources
These are modes of energy production, energy storage, or energy conservation, listed alphabetically. Note that not all sources are accepted as legitimate or have been proven to be tappable.
Primary nutritional groups
Primary nutritional groups are groups of organisms, divided in relation to the nutrition mode according to the sources of energy and carbon, needed for living, growth and reproduction. The sources of energy can be light and organic or inorganic compounds; the sources of carbon can be of organic or inorganic origin.
The terms "aerobic respiration", "anaerobic respiration" and "fermentation" do not refer to primary nutritional groups, but simply reflect the different use of possible electron acceptors in particular organisms, such as O in aerobic respiration, or nitrate (NO), sulfate (SO) or fumarate in anaerobic respiration, or various metabolic intermediates in fermentation. Because all ATP-generating steps in fermentation involve modifications of metabolic intermediates instead of the use of an electron transport chain fermentation is often referred to as "substrate-level phosphorylation".
List of largest energy companies
An energy company is a company which operates within the energy industry, which can be involved in the production and sale of energy, including fuel extraction, manufacturing, refining and distribution. The companies listed below are traded on public stock exchanges, as such state owned energy companies, such as Aramco are not included. However Saudi Arabia’s deputy crown prince, Mohammed bin Salman, revealed plans to float 5% of the shares of Aramco, creating a publicly traded company with a market capitalisation of around $2 trillion (almost three times that of Apple).
Abundance of the chemical elements
The elements – that is, ordinary (baryonic) matter made of protons, neutrons, and electrons, are only a small part of the content of the Universe. Cosmological observations suggest that only 4.6% of the universe's energy (including the mass contributed by energy, E = mc² ↔ m = E / c²) comprises the visible baryonic matter that constitutes stars, planets, and living beings. The rest is thought to be made up of dark energy (68%) and dark matter (27%). These are forms of matter and energy believed to exist on the basis of scientific theory and observational deductions, but they have not been directly observed and their nature is not well understood.
Alternative energy
Over the last three years publicly traded alternative energy companies have been very volatile, with some 2007 returns in excess of 100%, some 2008 returns down 90% or more, and peak-to-trough returns in 2009 again over 100%. In general there are three sub-segments of "alternative" energy investment: solar energy, wind energy and hybrid electric vehicles. Alternative energy sources which are renewable and have lower carbon emissions than fossil fuels are hydropower, wind energy, solar energy, geothermal energy, and bio fuels. Each of these four segments involve very different technologies and investment concerns.
Life-cycle assessment
A problem the energy analysis method cannot resolve is that different energy forms (heat, electricity, chemical energy etc.) have different quality and value even in natural sciences, as a consequence of the two main laws of thermodynamics. A thermodynamic measure of the quality of energy is exergy. According to the first law of thermodynamics, all energy inputs should be accounted with equal weight, whereas by the second law diverse energy forms should be accounted by different values.
Embodied energy
The main methods of embodied energy accounting as they are used today grew out of Wassily Leontief's input-output model and are called "Input-Output Embodied Energy analysis". Leontief's input-output model was in turn an adaptation of the neo-classical theory of general equilibrium with application to "the empirical study of the quantitative interdependence between interrelated economic activities". According to Tennenbaum Leontief's Input-Output method was adapted to embodied energy analysis by Hannon to describe ecosystem energy flows. Hannon's adaptation tabulated the total direct and indirect energy requirements (the "energy intensity") for each output made by the system. The total amount of energies, direct and indirect, for the entire amount of production was called the "embodied energy".