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 natural sciences 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.
With reference to the popular phrases: energy crisis and the need to conserve energy the usage of the term energy can be viewed to be in contradiction with the Law of conservation of energy in natural sciences. Energy conservation practices are demand side efforts targeted at conserving available energy resources.
Production and consumption of energy resources is very important to the global economy. All economic activity requires energy resources, whether to manufacture goods, provide transportation, run computers and other machines.
The citizens of the United States first became aware of an energy crisis in October 1973, when OPEC, the Organization of Petroleum Exporting Countries, embargoed exports of oil to the US , producing gas station lines that sometimes went on for miles and hoisting the price of oil from $3 to $11 per barrel by January, 1974. In response, President Richard Nixon called for "Project Independence." The goal? In Nixon's words, "At the end of this decade, in the year 1980, the United States will not be dependent on any other country for the energy we need to provide our jobs, to heat our homes, and to keep our transportation moving." In 1977, President Jimmy Carter called the crusade for energy independence, "the moral equivalent of war" and put it high on the nation's priority list. The crusade for energy independence was stopped when the administration of President Ronald Reagan pulled the plug on funding for alternative energy research and development in the 1980s. But the phrase "energy independence" has hung in as part of the American vocabulary.
New fears of energy crises have arisen thanks to the concept of peak oil and a new recognition in 2007 that China and India wanted the standard of living that had previously been the sole province of North Americans, Europeans and the Japanese. To achieve that standard would take the development of renewable wind, solar and geothermal sources. Some say that each of these renewable energy sources is individually capable of supplying all of earth's energy needs. Others say that these terrestrial energy resources are limited and that our long term energy needs will be served best by a broad portfolio of energy options, including solar energy harvested from the nearly infinite supplies in space The space approach is called space solar power and is advocated by groups like the National Space Society, the National Space Foundation, the Foundation for the Future and the Space Development Steering Committee.
Space solar power advocates point out that wind and solar are intermittent and require hydrostorage or other replacement when they are not available. Terrestrial solar power and wind farms take large amounts of space. Real estate on earth is limited, say the Space Solar Power advocates. Eventually the needs for land for these projects will clash with the interests of conservationists intent on keeping desert ecosystems and coastal views intact. Terrestrial solar energy--earth-based solar energy--suffers another disadvantage. It is shut down completely for twelve hours or so each day by a recurring meteorological anomaly called night.
Space solar power, say the SSP advocates, is available 24/7. The solar energy that falls on a square millimeter of collection apparatus in space has six times the energy it has if collected on the earth's surface. Space solar power does not require an expensive terrestrial distribution infrastructure. It can be beamed to any location in which a receiving apparatus, a rectenna, is built. This is an advantage for newly-electrifying rural areas in countries like China and India. But, most important, the energy available above our atmosphere meets the needs for an increased quality of life worldwide by virtue of the fact that it is potentially endless.
Burning fossil fuels for electricity generation also releases trace metals such as beryllium, cadmium, chromium, copper, manganese, mercury, nickel, and silver into the environment, which also act as pollutants. Certain renewable energy technologies do not pollute the environment in the same ways, and therefore can help contribute to a cleaner energy future for the world. Renewable energy technologies available for electricity production include biofuels, solar power, tidal power, wind turbines, hydroelectric power etc. However, serious environmental concerns have been articulated by several environmental activists regarding some of these modes of electricity generation. According to them, some pollution is invariably produced during the manufacture and retirement of the materials associated with the machinery used in these technologies. There is, however, general agreement that the most effective way to save the environment from expanding energy production is energy conservation.
Scientists have realized that the known energy resources may not suffice forever, there is thus an urgent need to explore new avenues, which include prospecting for newer territories rich in oil or gas or methods for producing energy resources using methods that have been explored very little. While some scientists are busy in exploring the possibility of cold fusion many countries are diverting significant economic resources towards space exploration Space exploration of long duration demands compact energy resources because the huge consumption of energy resources by a large size spacecraft cannot be met by chemical portable energy resources carried on board from the Earth. For missions to the outer solar system, compact nuclear power sources (in the form of nuclear reactors or radioisotope thermoelectric generators) are a necessity. It has been proposed to explore annihilation of matter for this purpose, although no practical way of producing significant amounts of antimatter, or storing them is presently known (these systems are not new ways of generating energy, only ways of storing it). Yet another field of research to store energy in a new way is through artificial photosynthesis, a process being actively researched to convert the carbon dioxide into useful fuel, other than biomass without the intervention of plants. However, artificial photosynthesis is also not a new energy source, but is ultimately simply another application of solar energy--- one which uses the energy of sunlight to do chemistry directly.
Since the cost of energy has become a significant factor in the performance of economy of societies, management of energy resources has become very crucial. Energy management involves utilizing the available energy resources more effectively that is with minimum incremental costs. Many times it is possible to save expenditure on energy without incorporating fresh technology by simple management techniques. Most often energy management is the practice of using energy more efficiently by eliminating energy wastage or to balance justifiable energy demand with appropriate energy supply. The process couples energy awareness with energy conservation.
Since energy plays an essential role in industrial societies, the ownership and control of energy resources plays an increasing role in politics. At the national level, governments seek to influence the sharing (distribution) of energy resources among various sections of the society through pricing mechanisms; or even who owns resources within their borders. They may also seek to influence the use of energy by individuals and business in an attempt to tackle environmental issues.
The most recent international political controversy regarding energy resources is in the context of the Iraq wars. Some political analysts maintain that the hidden reason for both 1991 and 2003 wars can be traced to strategic control of international energy resources. Others counter this analysis with the numbers related to its economics. According to the latter group of analysts, U.S. has spent about $336 billion in Iraq as compared with a background current value of $25 billion per year budget for the entire U.S. oil import dependence See Energy wars
Producing energy to sustain human needs is an essential social activity, and a great deal of effort goes into the activity. While most of such effort is limited towards increasing the production of electricity and oil, newer ways of producing usable energy resources from the available energy resources are being explored. One such effort is to explore means of producing hydrogen fuel from water. Though hydrogen use is environmentally friendly, its production requires energy and existing technologies to make it, are not very efficient. Research is underway to explore enzymatic decomposition of biomass..
Other forms of conventional energy resources are also being used in new ways. Coal gasification and liquefaction are recent technologies that are becoming attractive after the realization that oil reserves, at present consumption rates, may be rather short lived. See alternative fuels.
All societies require materials and food to be transported over distances, generally against some force of friction. Since application of force over distance requires the presence of a source of usable energy, such sources are of great worth in society.
While energy resources are an essential ingredient for all modes of transportation in society, the transportation of energy resources is becoming equally important. Energy resources are invariably located far from the place where they are consumed. Therefore their transportation is always in question. Some energy resources like liquid or gaseous fuels are transported using tankers or pipelines, while electricity transportation invariably requires a network of grid cables. The transportation of energy, whether by tanker, pipeline, or transmission line, poses challenges for scientists and engineers, policy makers, and economists to make it more risk-free and efficient.
Ever since humanity discovered various energy resources available in nature, it has been inventing devices, known as machines, that make life more comfortable by using energy resources. Thus, although the primitive man knew the utility of fire to cook food, the invention of devices like gas burners and microwave ovens has increased the usage of energy for this purpose alone manifold. The trend is the same in any other field of social activity, be it construction of social infrastructure, manufacturing of fabrics for covering; porting; printing; decorating, for example textiles, air conditioning; communication of information or for moving people and goods (automobiles).