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.
is the source of energy for most of life on Earth. As a star, the Sun is heated to high temperatures by the conversion of nuclear binding energy
due to the fusion of hydrogen in its core. This energy is ultimately transferred
(released) into space mainly in the form of radiant (light) energy
In physics, energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object. 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 SI unit of energy is the joule, which is the energy transferred to an object by the work of moving it a distance of 1 metre against a force of 1 newton.
Common forms of energy include the kinetic energy of a moving object, the potential energy stored by an object's position in a force field (gravitational, electric or magnetic), the elastic energy stored by stretching solid objects, the chemical energy released when a fuel burns, the radiant energy carried by light, and the thermal energy due to an object's temperature.
Mass and energy are closely related. 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. For example, after heating an object, its increase in energy could be measured as a small increase in mass, with a sensitive enough scale.
Living organisms require energy to stay alive, such as the energy humans get from food. Human civilization requires energy to function, which it gets from energy resources such as fossil fuels, nuclear fuel, or renewable energy. The processes of Earth's climate and ecosystem are driven by the radiant energy Earth receives from the sun and the geothermal energy contained within the earth.
Ethanol fuel in Brazil
provides a ~22% ethanol blend used nationwide, plus 100% hydrous ethanol
for four million cars. The Brazilian ethanol program provided nearly 700,000 jobs in 2003, and cut 1975–2002 oil imports by a cumulative undiscounted total of US$50 billion. Brazil gets more than 30% of its automobile fuels from sugar cane-based ethanol.
The Brazilian government provided three important initial drivers for the ethanol industry: guaranteed purchases by the state-owned oil company Petrobras, low-interest loans for agro-industrial ethanol firms, and fixed gasoline and ethanol prices where hydrous ethanol sold for 59% of the government-set gasoline price at the pump. These pump-primers have made ethanol production competitive yet unsubsidized.
In recent years, the Brazilian untaxed retail price of hydrous ethanol has
been lower than that of gasoline per gallon. Approximately US$50 million has recently been allocated for research and projects focused on advancing the obtention of ethanol from sugarcane in São Paulo. Read more...
Did you know?
- Positive lightning bolts are typically six to ten times more powerful than normal lightning — and aircraft are not designed to withstand them?
- Dark energy is a hypothetical form of energy which permeates all of space?
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