Energy development
Future energy development faces great challenges due to an increasing world population, demands for higher standards of living, a need for less pollution, a need to avert global warming, and a possible end to fossil fuels (see Hubbert peak theory). Without energy, the world's entire industrialized infrastructure would collapse; agriculture, transportation, waste collection, information technology, communications and much of the prerequisites that a developed nation takes for granted. A shortage of the energy needed to sustain this infrastructure could lead to a Malthusian catastrophe.
General considerations
Main article: Energy development
Almost all forms of terrestrial energy, such as fossil fuels, solar, wind, ocean thermal, and hydropower, can be traced back to energy received from the sun's fusion reactions. The only exceptions are tidal, nuclear, and geothermal power. Tidal energy comes from the gravitational potential energy of the Earth/Moon system. Geothermal energy is believed to be generated primarily by radioactive decay inside the Earth.
Main article: Energy development
Almost all forms of terrestrial energy, such as fossil fuels, solar, wind, ocean thermal, and hydropower, can be traced back to energy received from the sun's fusion reactions. The only exceptions are tidal, nuclear, and geothermal power. Tidal energy comes from the gravitational potential energy of the Earth/Moon system. Geothermal energy is believed to be generated primarily by radioactive decay inside the Earth.
Most human energy sources today use energy from sunlight, in the form of fossil fuels (coal, oil and gas). Once the stored forms are used up (assuming no contribution from the three previous energy sources and no energy from space exploration) then the long-term energy usage of humanity is limited to that from the sunlight falling on Earth. The total energy consumption of humanity today is equivalent to about 0.1-0.01 percent of that. But humanity cannot exploit most of this energy since it also provides the energy for almost all other lifeforms and drives the weather cycle.
U.S. energy consumption by sectors.
World energy production by source in 2004: Oil 40%, coal 23.3%, natural gas 22.5%, hydroelectric 7.0%, nuclear 6.5%, biomass and other 0.7%. In the U.S., transportation accounted for 28% of all energy use and 70% of petroleum use in 2001; 97% of transportation fuel was petroleum.
The United Nations projects that world population will stabilize in 2075 at nine billion due to the demographic transition. Birth rates are now falling in most developing nations and the population would decrease in several developed nations if there was no immigration. Since 1970, each 1 percent increase in the gross world product has yielded a 0.64 percent increase in energy consumption.
In geology, resources refer to the amount of a specific substance that may be present in a deposit. This definition does not take into account the economic feasibility of exploitation or the fact that resources may not be recoverable using current or future technology. Reserves constitute those resources that are recoverable using current technology. They can be recovered economically under current market conditions. This definition takes into account current mining technology and the economics of recovery, including mining and transport costs, government royalties and current market prices. Reserves decrease when prices are too low for some of the substance to be recovered economically, and increase when higher prices make more of the substance economically recoverable. Neither of these terms consider the energy required for exploitation (except as reflected in economic costs) or whether there is a net energy gain or loss.
Energy production usually requires an energy investment. Drilling for oil or building a wind power plant requires energy. The fossil fuel resources (see above) that are left are often increasingly difficult to extract and convert. They may thus require increasingly higher energy investments. If the investment is greater than the energy produced, then the fossil resource is no longer an energy source. This means that a large part of the fossil fuel resources and especially the non-conventional ones cannot be used for energy production today. Such resources may still be exploited economically in order to produce raw materials for plastics, fertilizers or even transportation fuel but now more energy is consumed than produced. (They then become similar to ordinary mining reserves, economically recoverable but not net positive energy sources.) New technology may ameliorate this problem if it can lower the energy investment required to extract and convert the resources, although ultimately basic physics sets limits that cannot be exceeded.
U.S. energy consumption by sectors.
World energy production by source in 2004: Oil 40%, coal 23.3%, natural gas 22.5%, hydroelectric 7.0%, nuclear 6.5%, biomass and other 0.7%. In the U.S., transportation accounted for 28% of all energy use and 70% of petroleum use in 2001; 97% of transportation fuel was petroleum.
The United Nations projects that world population will stabilize in 2075 at nine billion due to the demographic transition. Birth rates are now falling in most developing nations and the population would decrease in several developed nations if there was no immigration. Since 1970, each 1 percent increase in the gross world product has yielded a 0.64 percent increase in energy consumption.
In geology, resources refer to the amount of a specific substance that may be present in a deposit. This definition does not take into account the economic feasibility of exploitation or the fact that resources may not be recoverable using current or future technology. Reserves constitute those resources that are recoverable using current technology. They can be recovered economically under current market conditions. This definition takes into account current mining technology and the economics of recovery, including mining and transport costs, government royalties and current market prices. Reserves decrease when prices are too low for some of the substance to be recovered economically, and increase when higher prices make more of the substance economically recoverable. Neither of these terms consider the energy required for exploitation (except as reflected in economic costs) or whether there is a net energy gain or loss.
Energy production usually requires an energy investment. Drilling for oil or building a wind power plant requires energy. The fossil fuel resources (see above) that are left are often increasingly difficult to extract and convert. They may thus require increasingly higher energy investments. If the investment is greater than the energy produced, then the fossil resource is no longer an energy source. This means that a large part of the fossil fuel resources and especially the non-conventional ones cannot be used for energy production today. Such resources may still be exploited economically in order to produce raw materials for plastics, fertilizers or even transportation fuel but now more energy is consumed than produced. (They then become similar to ordinary mining reserves, economically recoverable but not net positive energy sources.) New technology may ameliorate this problem if it can lower the energy investment required to extract and convert the resources, although ultimately basic physics sets limits that cannot be exceeded.
The classification of energy sources into renewables and non-renewables is not without problems. Geothermal power and hydroelectric power are classified as renewable energy but geothermal sites eventually cool down and hydroelectric dams gradually become filled with silt, which may be very expensive to remove. Although it can be argued that while a specific location may be depleted, the total amount of potential geothermal and hydroelectric power is not and a new power plant may sometimes be built on a different location. Nuclear power is not classified as a renewable but the amount of uranium in the seas may continue to be replenished by rivers through erosion of underground resources for as long as the remaining life of the Sun. Fossil fuels are finite but hydrocarbon fuel may be produced in several ways as described below.
Many of the current or potential future power production numbers given below do not subtract the energy consumed due to loss of energy from constructing the power facilities and distribution network, energy distribution itself, maintenance, inevitable replacement of old power production facilities and distribution network, backup capacity due to intermittent output, and energy required to reverse damage to the environment and other externalities. Net power production using life cycle analysis is more correct but more difficult and has many new uncertain factors.
Many of the current or potential future power production numbers given below do not subtract the energy consumed due to loss of energy from constructing the power facilities and distribution network, energy distribution itself, maintenance, inevitable replacement of old power production facilities and distribution network, backup capacity due to intermittent output, and energy required to reverse damage to the environment and other externalities. Net power production using life cycle analysis is more correct but more difficult and has many new uncertain factors.
From wikipedia
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