Energy development[1][2][3] is a field of endeavor focused on making available sufficient primary energy sources[4] and secondary energy forms to meet the needs of society.[5][6][7][8][9] These endeavors encompass those which provide for the production of conventional, alternative and renewable sources of energy, and for the recovery and reuse of energy that would otherwise be wasted. Energy conservation[note 2] and efficiency measures[note 3] reduce the impact of energy development, and can have benefits to society with changes in economic cost and with changes in the environmental effects.
Contemporary industrial societies use primary and secondary energy sources for transportation and the production of many manufactured goods. Also, large industrial populations have various generation and delivery services for energy distribution and end-user utilization.[note 4] This energy is used by people who can afford the cost to live under various climatic conditions through the use of heating, ventilation, and/or air conditioning. Level of use of external energy sources differs across societies, along with the convenience, levels of traffic congestion, pollution sources[10] and availability of domestic energy sources.
Thousands of people in society are employed in the energy industry, of which subjectively influence and impact behaviors. The conventional industry comprises the petroleum industry[note 5] the gas industry,[note 6] the electrical power industry[note 7] the coal industry, and the nuclear power industry. New energy industries include the renewable energy industry, comprising alternative and sustainable manufacture, distribution, and sale of alternative fuels. While there is the development of new hydrocarbon sources,[11] including deepwater/horizontal drilling and fracking, are contentiously underway, commitments to mitigate climate change are driving efforts to develop sources of alternative and renewable energy.
Colloquially, and in non-scientific literature, the terms power,[note 8] fuels, and energy can be used as synonyms, but in the field of energy technology they possess different distinct meanings that are associated with them. An energy source is usually in the form of a closed system, the element that provides the energy by conversion from another energy form; However, the energy can be quantitative, the balance sheet is capable of containing open system energy transfers.[note 9] Illustrative of this can be the emanations from the sun, which with its nuclear fusion is the most important energy source for the Earth[note 10] and which provides its energy in the form of radiation.
The natural elements[note 11] of the material world exist in forms that can be converted into usable energy and are resources from which society can obtain energy to produce heat, light, and motion (among the many uses). According to their nature, the power plants can be classified into:
Primary : They are found in nature: wind, water, solar,[note 12] wood, coal, oil, nuclear.
Secondary : Are those obtained from primary energy sources: electricity, gas.
Classified according to the energy reserves of the energy source used and the regeneration capacity with:
renewable: When the energy source used is freely regenerated in a short period and there are practically limitless reserves; An example is the solar energy that is the source of energy from the sun, or the wind[note 13] used as an energy resource. Renewable energies are:
original solar
natural wind (atmospheric flows)
natural geothermal
oceanic tidal
natural waterfall (hydraulic flows)
natural plant: paper, wood
natural animal: wax, grease,[note 14] pack animals and sources of mechanical energy[note 15]
nonrenewable: They are coming from energy limited sources on Earth in quantity and, therefore, are exhaustible. The non-renewable energy sources include, non-exclusively:
fossil source: petroleum, natural gas, coal
original mineral/chemical: uranium, shale gas[note 16]
So, for example, shale gas is secondary non-renewable. Wind is a primary renewable.
The principle stated by Antoine Lavoisier on the conservation of matter applies to energy development:[note 17] "nothing is created." Thus any energy "production" is actually a recovery transformation of the forms of energy whose origin is that of the universe.
For example, a bicycle dynamo turns in part from the kinetic energy (speed energy) of the movement of the cyclist and converting it into electrical energy will transfer in particular to its lights producing light, that is to say light energy, via the heating of the filament of the bulb and therefore heat (thermal energy). But the kinetic energy of the rider is itself biochemical energy (the ATP muscle cells) derived from the chemical energy of sugars synthesized by plants who use light energy from the sun, which runs from the nuclear energy produced by fusion of atoms of hydrogen, the material itself constitute a form of energy, called "mass energy".
Fossil fuels[edit]
The Moss Landing Power Plant burns natural gas to produce electricity in California.
Natural gas drilling rig in Texas.
Main articles: Fossil fuel and Peak oil
Fossil fuel (primary non-renewable fossil) sources burn coal or hydrocarbon fuels, which are the remains of the decomposition of plants and animals. There are three main types of fossil fuels: coal, petroleum, and natural gas. Another fossil fuel, liquefied petroleum gas (LPG), is principally derived from the production of natural gas. Heat from burning fossil fuel is used either directly for space heating and process heating, or converted to mechanical energy for vehicles, industrial processes, or electrical power generation.
Fossil energy is from recovered fossils (like brown coal, hard coal, peat, natural gas and crude oil) and are originated in degradated products of dead plants and animals. These fossil fuels are based on the carbon cycle and thus allow stored (historic solar) energy to be recycled today. In 2005, 81% were of the world's energy needs met from fossil sources.[12] Biomass is also derived from wood and other organic wastes and modern remains. The technical development of fossil fuels in the 18th and 19th Century set the stage for the Industrial Revolution.
Fossil fuels make up the bulk of the world's current primary energy sources. The technology and infrastructure already exist for the use of fossil fuels. Petroleum energy density in terms of volume (cubic space) and mass (weight) ranks currently above that of alternative energy sources (or energy storage devices, like a battery). Fossil fuels are currently economical, and suitable for decentralized energy use.
Dependence on fossil fuels from regions or countries creates energy security risks for dependent countries.[13][14][15][16][17] Oil dependence in particular has led to war,[18] funding of radicals,[19] monopolization,[20] and socio-political instability.[21] Fossil fuels are non-renewable, un-sustainable resources, which will eventually decline in production[22] and become exhausted, with consequences to societies that remain dependent on them. Fossil fuels are actually slowly forming continuously, but are being consumed quicker than are formed.[note 18] Extracting fuels becomes increasingly extreme as society consumes the most accessible fuel deposits. Extraction in fuel mines get intensive and oil rigs drill deeper (going further out to sea).[23] Extraction of fossil fuels results in environmental degradation, such as the strip mining and mountaintop removal of coal.
Fuel efficiency is a form of thermal efficiency, meaning the efficiency of a process that converts chemical potential energy contained in a carrier fuel into kinetic energy or work. The fuel economy is the energy efficiency of a particular vehicle, is given as a ratio of distance travelled per unit of fuel consumed. Weight-specific efficiency (efficiency per unit weight) may be stated for freight, and passenger-specific efficiency (vehicle efficiency per passenger). The inefficient atmospheric combustion (burning) of fossil fuels in vehicles, buildings, and power plants contributes to urban heat islands.[24]
Conventional production of oil has peaked, conservatively, between 2007 to 2010.[note 19] In 2010, it was estimated that an investment in non-renewable resources of $8 trillion would be required to maintain current levels of production for 25 years.[25] In 2010, governments subsidized fossil fuels by an estimated $500 billion a year.[26] Fossil fuels are also a source of greenhouse gas emissions, leading to concerns about global warming if consumption is not reduced.
The combustion of fossil fuels leads to the release of pollution into the atmosphere. The fossil fuels are mainly based on organic carbon compounds. They are according to the IPCC the causes of the global warming.[27] During the combustion with oxygen in the form of heat energy, carbon dioxide released. Depending on the composition and purity of the fossil fuel also results in other chemical compounds such as nitrogen oxides and soot and fine dust alternativey. Greenhouse gas emissions result from fossil fuel-based electricity generation. Typical megawatt coal plant produces billions of kilowatt hours per year.[28][note 20] From this generation, the carbon dioxide, sulfur dioxide, small airborne particles, nitrogen oxides (NOx) (ozone (smog)), carbon monoxide (CO), hydrocarbons, volatile organic compounds (VOC), mercury, arsenic, lead, cadmium, other heavy metals, and uranium traces are produced.[29][30]
Nuclear power, or nuclear energy, is the use of exothermic nuclear processes,[31] to generate useful heat and electricity. The term includes nuclear fission, nuclear decay and nuclear fusion. Presently the nuclear fission of elements in the actinide series of the periodic table produce the vast majority of nuclear energy in the direct service of humankind, with nuclear decay processes, primarily in the form of geothermal energy, and radioisotope thermoelectric generators, in niche uses making up the rest. Nuclear (fission) power stations, excluding the contribution from naval nuclear fission reactors, provided about 5.7% of the world's energy and 13% of the world's electricity in 2012.[32] In 2013, the IAEA report that there are 437 operational nuclear power reactors,[33] in 31 countries,[34] although not every reactor is producing electricity.[35] In addition, there are approximately 140 naval vessels using nuclear propulsion in operation, powered by some 180 reactors.[36][37][38] As of 2013, attaining a net energy gain from sustained nuclear fusion reactions, excluding natural fusion power sources such as the Sun, remains an ongoing area of international physics and engineering research. More than 60 years after the first attempts, commercial fusion power production remains unlikely before 2050.[39]
There is an ongoing debate about nuclear power.[40][41][42] Proponents, such as the World Nuclear Association, the IAEA and Environmentalists for Nuclear Energy contend that nuclear power is a safe, sustainable energy source that reduces carbon emissions.[43] Opponents, such as Greenpeace International and NIRS, contend that nuclear power poses many threats to people and the environment.[44][45][46]
Nuclear power plant accidents include the Chernobyl disaster (1986), Fukushima Daiichi nuclear disaster (2011), and the Three Mile Island accident (1979).[47] There have also been some nuclear submarine accidents.[47][48][49] In terms of lives lost per unit of energy generated, analysis has determined that nuclear power has caused less fatalities per unit of energy generated than the other major sources of energy generation. Energy production from coal, petroleum, natural gas and hydropower has caused a greater number of fatalities per unit of energy generated due to air pollution and energy accident effects.[50][51][52][53][54] However, the economic costs of nuclear power accidents is high, and meltdowns can take decades to clean up. The human costs of evacuations of affected populations and lost livelihoods is also significant.[55][56]
Along with other sustainable energy sources, nuclear power is a low carbon power generation method of producing electricity, with an analysis of the literature on its total life cycle emission intensity finding that it is similar to other renewable sources in a comparison of greenhouse gas(GHG) emissions per unit of energy generated.[57] With this translating into, from the beginning of nuclear power station commercialization in the 1970s, having prevented the emission of approximately 64 gigatonnes of carbon dioxide equivalent(GtCO2-eq) greenhouse gases, gases that would have otherwise resulted from the burning of fossil fuels in thermal power stations.[58]
As of 2012, according to the IAEA, worldwide there were 68 civil nuclear power reactors under construction in 15 countries,[33] approximately 28 of which in the Peoples Republic of China (PRC), with the most recent nuclear power reactor, as of May 2013, to be connected to the electrical grid, occurring on February 17, 2013 in Hongyanhe Nuclear Power Plant in the PRC.[59] In the USA, two new Generation III reactors are under construction at Vogtle. U.S. nuclear industry officials expect five new reactors to enter service by 2020, all at existing plants.[60] In 2013, four aging, uncompetitive, reactors were permanently closed.[61][62]
Japan's 2011 Fukushima Daiichi nuclear accident, which occurred in a reactor design from the 1960s, prompted a rethink of nuclear safety and nuclear energy policy in many countries.[63] Germany decided to close all its reactors by 2022, and Italy has banned nuclear power.[63] Following Fukushima, in 2011 the International Energy Agency halved its estimate of additional nuclear generating capacity to be built by 2035.[64][65]
Fission economics[edit]
Main article: Economics of new nuclear power plants
The economics of new nuclear power plants is a controversial subject, since there are diverging views on this topic, and multi-billion dollar investments ride on the choice of an energy source. Nuclear power plants typically have high capital costs for building the plant, but low direct fuel costs.
In recent years there has been a slowdown of electricity demand growth and financing has become more difficult, which has an impact on large projects such as nuclear reactors, with very large upfront costs and long project cycles which carry a large variety of risks.[66] In Eastern Europe, a number of long-established projects are struggling to find finance, notably Belene in Bulgaria and the additional reactors at Cernavoda in Romania, and some potential backers have pulled out.[66] Where cheap gas is available and its future supply relatively secure, this also poses a major problem for nuclear projects.[66]
Analysis of the economics of nuclear power must take into account who bears the risks of future uncertainties. To date all operating nuclear power plants were developed by state-owned or regulated utility monopolies[67][68] where many of the risks associated with construction costs, operating performance, fuel price, and other factors were borne by consumers rather than suppliers. Many countries have now liberalized the electricity market where these risks, and the risk of cheaper competitors emerging before capital costs are recovered, are borne by plant suppliers and operators rather than consumers, which leads to a significantly different evaluation of the economics of new nuclear power plants.[69]
Two of the four EPRs under construction (in Finland and France) are significantly behind schedule and substantially over cost.[70] Following the 2011 Fukushima Daiichi nuclear disaster, costs are likely to go up for currently operating and new nuclear power plants, due to increased requirements for on-site spent fuel management and elevated design basis threats.[71]
Hydrothermal 
