General energy facts

Energy is the ability to do work. It comes in various forms of thermal (heat), radiant (light), mechanical, electrical, chemical and nuclear energy. Energy is in everything.

Internationally recognized unit of measurement for energy is the SI unit of energy, the joule. Power is the rate used to transmit the energy and it is usually measured in watts.


Energy is used most commonly associated with energy resources, their development, consumption, consumption and conservation. Since economic activities such as manufacturing, transport, energy intensive, energy efficiency, energy dependence, energy security and price may be, are central concerns.

Renewable energy sources are solar energy, wind energy, geothermal energy, hydropower, bioenergy (bioethanol, biodiesel), ocean (tidal, wave, ocean thermal energy conversion OTEC). Renewable energy sources are often labeled as a sustainable energy sources.

Non-renewable energy sources, fossil fuels (oil, coal, natural gas) and nuclear energy. Fossil fuels are the most important energy source in the world today. Non-renewable energies are often labeled as non-sustainable energy sources.

Burst of energy. Time-lapse photography captures multiple cloud-to-ground lightning during a nighttime thunderstorm.

We use energy to want to do what we, from, to bake a jump shot our favorite cookies to sending astronauts into space - energy is there, so we have the power to do anything.

Food is stored energy. It is as a chemical stored potential energy. If your body uses the stored energy to do the work, there is kinetic energy.

Matter can be converted into energy, and energy into matter. One of the great insight of Einstein was to realize that matter and energy are really different forms of the same. The deep connection Einstein discovered between energy and mass is expressed in the equation E = mc2. Here E represents energy, m mass, and C2 is a very large number, the square of the speed of light.

Scientists from Columbia University, New York, and Lawrence Berkeley National Laboratory, Berkeley, California have shown that more energy cast by the sun than is radiated back into space, the earth energy "out of balance" and absorb the warming of the earth.

In physics, the law of conservation of energy states that the total amount of energy in any isolated system remains constant, but can not be rebuilt, although it may change forms.

According to the law of conservation of energy, energy can neither created (produced) are still self-destructed. It can only be transformed. So, if one measures the total energy of a system of particles whose interactions are not explicitly depend on time, it is noted that the total energy of the system always remains constant.

In physics and technology, energy transformation or energy conversion, any process of converting one form of energy to the other. Normally we have to transform unusable energy into usable with a variety of machines (cars, heaters, ...).

Photovoltaic cells are an easy way to get electricity. Solar energy is a sustainable and clean energy source.

Sustainable energy is the provision of energy that meets the needs of the present without compromising the ability of future generations to meet their own needs. Sustainable Energy has two key components: renewable energy and energy efficiency. With some other definition, sustainable energy energy renewable within a human life and does not cause long term damage to the environment.

Alternative energy is usually defined as from sources that do not deplete the natural resources or harm the environment. Typical examples of alternative energy sources are wind and solar energy.

Annual fossil fuel power plants convert between 36% and 48% of the fuel into electricity, the rest is lost as waste heat.

Energy storage is the storing of some form of energy that can be drawn at a later time to perform some useful operation. A device that stores energy is sometimes called an accumulator. Hydropower dams are a type of energy storage. The batteries are energy storage.

In physical cosmology, dark energy is a hypothetical exotic form of energy that permeates the entire space and tends to increase the rate of expansion of the universe.

Security of energy supply is therefore important for the functioning of modern economies. For this reason, almost all wars in the last 20 years or so mostly wars for control of energy sources (direct energy source, the control of energy transport routes, control of energy-rich countries ...).