Energy

In society and in the context of humanities, the word energy is used as a synonym of energy resources, and most often refers to substances like fuels, petroleum products and electricity in general. These are sources of usable energy, in that they can be easily transformed to other kinds of energy sources that can serve a particular useful purpose. This difference vis a vis energy in naturalsciences can lead to some confusion, because energy resources are not conserved in nature in the same way as energy is conserved in the context of physics. The actual energy content is always conserved, but when it is converted into heat for example, it usually becomes less useful to society, and thus appears to have been used up.
The use of energy has been a key in the development of the humansociety by helping it to control and adapt to the environment. Managing the use of energy is inevitable in any functional society. In the industrialized world the development of energy resources has become essential for agriculture, transportation, waste collection, information technology, communications that have become prerequisites of a developed society. The increasing use of energy since theIndustrial Revolution has also brought with it a number of serious problems, some of which, such as global warming, present potentially grave risks to the world.
Economics
Main articles: Energy economics and Energy industry
Production and consumption of energy resources is very important to the global economy. All economic activity requires energy resources, whether to manufacture goods, providetransportation, run computers and other machines.
The energy industry is a generic term for all of the industries involved the production and sale of energy, including fuel extraction, manufacturing, refining and distribution. Modern society consumes large amounts of fuel, and the energy industry is a crucial part of the infrastructure and maintenance of society in almost all countries.
EnvironmentEnergy and the environment are closely interlinked since energy comes via the environment and can have a negative effect on it. An increasing awareness of the effect of human activity on the natural environment has led to the use of sustainable energy and, in an increasingly populated world, the need for energy conservation and energy efficiency.
An increasing per capita demand and an increasingpopulation is placing a greater strain on natural resources. These resources include undammed rivers, clean air and retaining natural landscapes. Unsustainable energy demands, collectively across all forms of energy generation and cumulatively for every unit of energy, affect the quality and quantity of natural resources.
Sustainable energy is the provision of energy such that it meets the needsof the present without compromising the ability of future generations to meet their needs. A broader interpretation may allow inclusion of fossil fuels and nuclear fission as transitional sources while technology develops, as long as new sources are developed for future generations to use. A narrower interpretation includes only energy sources which are not expected to be depleted in a time framerelevant to the human race.
Sustainable energy sources are most often regarded as including all renewable sources, such as biofuels, solar heating, solar power, wind power, geothermal power and tidal power. It usually also includes technologies that improve energy efficiency. Conventional fission power is sometimes referred to as sustainable, but this is controversial politically due to concernsabout peak uranium, radioactive waste disposal and the risks of disaster due to accident, terrorism, or natural disaster.

--Consumption of energy resources, (e.g. turning on a light) requires resources and has an effect on the environment. Many electric power plants burn coal, oil or natural gas in order to generate electricity for energy needs. While burning these fossil fuels produces a...