Assignment
# 1Recent World’s Energy
Overview:-Energy Definitions:-
Energy is a property of every physical system, describing its ability to perform work.
When energy is released it is converted to either work (which implies motion of bodies or matter) or another form of energy such that the sum of work and other forms of energy is always conserved.
Forms of Energy:-
· Kinetic energy
· Potential energy
· Thermal energy
· Chemical energy
· Radiant energy
· Electrical energy
Renewable & Non-Renewable energy resources:-
· Renewable energy resource is that to be replaced rapidly by natural processes.
· Non-Renewable energy resource is that to be not replaced or is replaced only very slowly by natural processes.
Energy Units:-
Joule:
1 J = 1 newton.metre = 1 kg.m/s2.m = 1 kg.(m/s)2
Calorie:1 Cal = amount of heat needed to raise the temperature of 1 g of distilled water by 1 K at sea level and normal temperature (15°C).
1 Cal = 4.185 J
Units of Energy (continued):-
Barrel of Oil Equivalent (BOE):
Tonne of Oil Equivalent (toe):The tonne of oil equivalent (toe) is a unit of energy: the amount of energy released by burning one tonne of crude oil, approximately 42 GJ
British Thermal Unit:1 BTU = amount of heat needed to raise the
temperature of 1 lb. of water from 63°F to 64°F.
1 BTU = 252 Cal = 1054.6 J
Erg:1 Erg = g cm2/ s2 = 1×10−7 J.
kilowatt-hour:1 (kW h) = 3.6×106 J
Electronvolt (eV):1eV = 1.60217653×10−19 J
History of Mankind with The Energy:-
· Ancient discovery of fire and the possibility of burning wood made large amount of energy available for mankind, for the first time.
· Later (about 4000 years B.C.) cultural development began to accelerate.
· For several thousand years human energy demands were covered only by renewable energy sources.
· This remained only until the start of industrial revolution and the ability to transform heat into motion.
· Then industrial development and energy consumption accelerated rapidly.
· The revolution of energy technology based mainly on fossil fuels.
· It changed from the use of coal deposits to oil and natural gas fields on a global scale.
· It is only half a century since nuclear power began being used as an energy resource.
· Fundamental shift in the energy picture can be found in the enormous increase of energy demand since the middle of the last century.
· After this fossil-based period world nears the beginning of another major transition, away from fossil fuels and towards renewable energy resources once again.
· The last two centuries saw massive increase in global energy use, based mainly on burning cheap and plentiful fossil fuels.
· World population rose between 1900 and 2000 nearly four folds meanwhile primary energy use increased about twenty folds.
· Firewood used for the most of the 19 century. By the beginning 20 century coal was the dominant energy source.
· During the 1920s, oil in turn began to challenge and by the 1970s had overtaken it as the leading contributor to world supplies.
· By then, natural gas was also making a very substantial contribution, with nuclear energy and hydro power also supplying smaller but significant amounts.
· What does Sustainability mean ?
· Sustainability is the newest expression for the ethic involving human’s relationship with the environment, and the current generation's responsibility to future generations.
· Sustainability is a concept that links the interconnected components of economic, environmental, and human social issues.
· Sustainability means efficient use of resources for effective development that meets the needs of the present without disgracing the ability of future generations to meet their own needs.
· What is then sustainable energy resource?
· Which does not depleted by continued use. Whose usage does not involve the emission of pollutants or other hazards to the environment on a substantial scale.
· Energy is a universal wealth has provided to the whole of mankind.
· Every thing we see around us has cost a lot more to create (in terms of fuel consumption) than most of us are aware.
· Small car costs about five times more energy to build than it will actually consume in fuel during a service life of 200,000 miles.
· We (engineers) have to adopt the genuine philosophy of ‘build it’ to last forever, ‘maintain it’ to make it last forever.
Conclusions:-
Moreover we must utilize energy and raw material wisely: it is the moral obligation of our generation because energy and raw material shortage involves economic decline and poverty.
We must take care of the quality of life of the future generations as well as our’s.
We have to handle energy rationally which means;
· Economically and,
· Efficiently.
Fossil fuel:-
These are the proven energy reserves; real reserves may be up to a factor 4 larger. Significant uncertainty exists for these numbers. Estimating the remaining fossil fuels on the planet depends on a detailed understanding of the Earth's crust. While modern drilling technology makes it possible to drill wells in up to 3 km of water to verify the exact composition of the geology, one half of the ocean is deeper than 3 km, leaving about a third of the planet beyond the reach of detailed analysis.
In addition to uncertainty in real reserves, there is significant uncertainty in technological and economic factors that impact what percentage of reserves can be recovered gainfully. In general the easiest to reach deposits are the first extracted. Factors affecting the cost of exploiting the remaining reserves include the accessibility of fossil deposits, the level of sulfur and other pollutants in the oil and the coal, transportation costs, and societal instability in producing regions
Coal:-
Coal is the most abundant and burned fossil fuel. This was the fuel that launched the industrial revolution and has continued to grow in use; China, which already has many of the world's most polluted cities, was in 2007 building about two coal-fired power plants every week. Coal is the fastest growing fossil fuel and its large reserves would make it a popular candidate to meet the energy demand of the global community, short of global warming concerns and other pollutants. According to the International Energy Agency the proven reserves of coal are around 909 billion tonnes, which could sustain the current production rate for 155 years, although at a 5% growth per annum this would be reduced to 45 years, or until 2051. With the Fischer- Tropsch process it is possible to make liquid fuels such as diesel and jet fuel from coal. In the United States, 49% of electricity generation comes from burning coal.
Natural Gas:-
Natural gas is a widely available fossil fuel with estimated 850 000 km³ in recoverable reserves and at least that much more using enhanced methods to release shale gas. Improvements in technology and wide exploration led to a major increase in recoverable natural gas reserves as shale fracking methods were developed. At present usage rates, natural gas could supply most of the world's energy needs for between 100 and 250 years, depending on increase in consumption over time.
Oil:-
It is estimated that there may be 57 ZJ of oil reserves on Earth (although estimates vary from a low of 8 ZJ,[10] consisting of currently proven and recoverable reserves, to a maximum of 110 ZJ consisting of available, but not necessarily recoverable reserves, and including optimistic estimates for unconventional sources such as oil sands and oil shale. Current consensus among the 18 recognized estimates of supply profiles is that the peak of extraction will occur in 2020 at the rate of 93-million barrels per day (mbd). Current oil consumption is at the rate of 0.18 ZJ per year (31.1 billion barrels) or 85-mbd.
There is growing concern that peak oil production may be reached in the near future, resulting in severe oil price increases. A 2005 French Economics, Industry and Finance Ministry report suggested a worst-case scenario that could occur as early as 2013. There are also theories that peak of the global oil production may occur in as little as 2–3 years. The ASPO predicts peak year to be in 2010. Some other theories present the view that it has already taken place in 2005. World crude oil production (including lease condensates) according to US EIA data decreased from a peak of 73.720 mbd in 2005 to 73.437 in 2006, 72.981 in 2007, and 73.697 in 2008. According to peak oil theory, increasing production will lead to a more rapid collapse of production in the future, while decreasing production will lead to a slower decrease, as the bell-shaped curve will be spread out over more years.
In a stated goal of increasing oil prices to $75/barrel, which had fallen from a high of $147 to a low of $40, OPEC announced decreasing production by 2.2 mbd beginning 1 January 2009
Nuclear energy:-
The International Atomic Energy Agency estimates the remaining uranium resources to be equal to 2500 ZJ. This assumes the use of breeder reactors, which are able to create more fissile material than they consume. IPCC estimated currently proved economically recoverable uranium deposits for once-through fuel cycles reactors to be only 2 ZJ. The ultimately recoverable uranium is estimated to be 17 ZJ for once-through reactors and 1000 ZJ with reprocessing and fast breeder reactors.
Resources and technology do not constrain the capacity of nuclear power to contribute to meeting the energy demand for the 21st century. However, political and environmental concerns about nuclear safety and radioactive waste started to limit the growth of this energy supply at the end of last century, particularly due to a number of nuclear accidents. Concerns about nuclear proliferation (especially with plutonium produced by breeder reactors) mean that the development of nuclear power by countries such as Iran and Syria is being actively discouraged by the international community.
Although at the beginning of the 21st century uranium is the primary nuclear fuel worldwide, others such as thorium and hydrogen had been under investigation since the middle of the 20th century.
Thorium reserves significantly exceed those of uranium, and of course hydrogen is abundant. It is also considered by many to be easier to obtain than uranium. While uranium mines are enclosed underground and thus very dangerous for the miners, thorium is taken from open pits, and is estimated to be roughly three times as abundant as uranium in the Earth's crust.
Since the 1960s, numerous facilities throughout the world have burned Thorium.
Nuclear fusion:-
Alternatives for energy production through fusion of hydrogen has been under investigation since the 1950s. No materials can withstand the temperatures required to ignite the fuel, so it must be confined by methods which use no materials. Magnetic and inertial confinement are the main alternatives (Cadarache, Inertial confinement fusion) both of which are hot research topics in the early years of the 21st century.
Fusion power is the process driving the sun and other stars. It generates large quantities of heat by fusing the nuclei of hydrogen or helium isotopes, which may be derived from seawater. The heat can theoretically be harnessed to generate electricity. The temperatures and pressures needed to sustain fusion make it a very difficult process to control. Fusion is theoretically able to supply vast quantities of energy, with relatively little pollution. Although both the United States and the European Union, along with other countries, are supporting fusion research (such as investing in the ITER facility), according to one report, inadequate research has stalled progress in fusion research for the past 20 years.
Renewable resources:-
Renewable resources are available each year, unlike non-renewable resources, which are eventually depleted. A simple comparison is a coal mine and a forest. While the forest could be depleted, if it is managed it represents a continuous supply of energy, vs. the coal mine, which once has been exhausted is gone. Most of earth's available energy resources are renewable resources. Renewable resources account for more than 93 percent of total U.S. energy reserves. Annual renewable resources were multiplied times thirty years for comparison with non-renewable resources. In other words, if all non-renewable resources were uniformly exhausted in 30 years, they would only account for 7 percent of available resources each year, if all available renewable resources were developed
Solar energy:-
Renewable energy sources are even larger than the traditional fossil fuels and in theory can easily supply the world's energy needs. 89 PW of solar power falls on the planet's surface. While it is not possible to capture all, or even most, of this energy, capturing less than 0.02% would be enough to meet the current energy needs. Barriers to further solar generation include the high price of making solar cells and reliance on weather patterns to generate electricity. Also, current solar generation does not produce electricity at night, which is a particular problem in high northern and southern latitude countries; energy demand is highest in winter, while availability of solar energy is lowest. This could be overcome by buying power from countries closer to the equator during winter months, and may also be addressed with technological developments such as the development of inexpensive energy storage. Globally, solar generation is the fastest growing source of energy, seeing an annual average growth of 35% over the past few years. Japan, Europe, China, U.S. and India are the major growing investors in solar energy. Solar power's share of worldwide electricity usage at the end of 2014 was 1%
Wind power:-
The available wind energy estimates range from 300 TW to 870 TW. Using the lower estimate, just 5% of the available wind energy would supply the current worldwide energy needs. Most of this wind energy is available over the open ocean. The oceans cover 71% of the planet and wind tends to blow more strongly over open water because there are fewer obstructions.
Wave and tidal
power:-
At the end of 2005, 0.3 GW of electricity was produced by tidal power. Due to the tidal forces created by the Moon (68%) and the Sun (32%), and the Earth's relative rotation with respect to Moon and Sun, there are fluctuating tides. These tidal fluctuations result in dissipation at an average rate of about 3.7 TW.
Another physical limitation is the energy available in the tidal fluctuations of the oceans, which is about 0.6 EJ (exajoule).Note this is only a tiny fraction of the total rotational energy of the Earth. Without forcing, this energy would be dissipated (at a dissipation rate of 3.7 TW) in about four semi-diurnal tide periods. So, dissipation plays a significant role in the tidal dynamics of the oceans. Therefore, this limits the available tidal energy to around 0.8 TW (20% of the dissipation rate) in order not to disturb the tidal dynamics too much.
Waves are derived from wind, which is in turn derived from solar energy, and at each conversion there is a drop of about two orders of magnitude in available energy. The total power of waves that wash against our shores add up to 3 TW.
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Energy is a property of every physical system, describing its ability to perform work.
When energy is released it is converted to either work (which implies motion of bodies or matter) or another form of energy such that the sum of work and other forms of energy is always conserved.
Forms of Energy:-
· Kinetic energy
· Potential energy
· Thermal energy
· Chemical energy
· Radiant energy
· Electrical energy
Renewable & Non-Renewable energy resources:-
· Renewable energy resource is that to be replaced rapidly by natural processes.
· Non-Renewable energy resource is that to be not replaced or is replaced only very slowly by natural processes.
Energy Units:-
Joule:
1 J = 1 newton.metre = 1 kg.m/s2.m = 1 kg.(m/s)2
Calorie:1 Cal = amount of heat needed to raise the temperature of 1 g of distilled water by 1 K at sea level and normal temperature (15°C).
1 Cal = 4.185 J
Barrel of Oil Equivalent (BOE):
Tonne of Oil Equivalent (toe):The tonne of oil equivalent (toe) is a unit of energy: the amount of energy released by burning one tonne of crude oil, approximately 42 GJ
British Thermal Unit:1 BTU = amount of heat needed to raise the
temperature of 1 lb. of water from 63°F to 64°F.
1 BTU = 252 Cal = 1054.6 J
Erg:1 Erg = g cm2/ s2 = 1×10−7 J.
kilowatt-hour:1 (kW h) = 3.6×106 J
Electronvolt (eV):1eV = 1.60217653×10−19 J
History of Mankind with The Energy:-
· Ancient discovery of fire and the possibility of burning wood made large amount of energy available for mankind, for the first time.
· Later (about 4000 years B.C.) cultural development began to accelerate.
· For several thousand years human energy demands were covered only by renewable energy sources.
· This remained only until the start of industrial revolution and the ability to transform heat into motion.
· Then industrial development and energy consumption accelerated rapidly.
· The revolution of energy technology based mainly on fossil fuels.
· It changed from the use of coal deposits to oil and natural gas fields on a global scale.
· It is only half a century since nuclear power began being used as an energy resource.
· Fundamental shift in the energy picture can be found in the enormous increase of energy demand since the middle of the last century.
· After this fossil-based period world nears the beginning of another major transition, away from fossil fuels and towards renewable energy resources once again.
· The last two centuries saw massive increase in global energy use, based mainly on burning cheap and plentiful fossil fuels.
· World population rose between 1900 and 2000 nearly four folds meanwhile primary energy use increased about twenty folds.
· Firewood used for the most of the 19 century. By the beginning 20 century coal was the dominant energy source.
· During the 1920s, oil in turn began to challenge and by the 1970s had overtaken it as the leading contributor to world supplies.
· By then, natural gas was also making a very substantial contribution, with nuclear energy and hydro power also supplying smaller but significant amounts.
· What does Sustainability mean ?
· Sustainability is the newest expression for the ethic involving human’s relationship with the environment, and the current generation's responsibility to future generations.
· Sustainability is a concept that links the interconnected components of economic, environmental, and human social issues.
· Sustainability means efficient use of resources for effective development that meets the needs of the present without disgracing the ability of future generations to meet their own needs.
· What is then sustainable energy resource?
· Which does not depleted by continued use. Whose usage does not involve the emission of pollutants or other hazards to the environment on a substantial scale.
· Energy is a universal wealth has provided to the whole of mankind.
· Every thing we see around us has cost a lot more to create (in terms of fuel consumption) than most of us are aware.
· Small car costs about five times more energy to build than it will actually consume in fuel during a service life of 200,000 miles.
· We (engineers) have to adopt the genuine philosophy of ‘build it’ to last forever, ‘maintain it’ to make it last forever.
Moreover we must utilize energy and raw material wisely: it is the moral obligation of our generation because energy and raw material shortage involves economic decline and poverty.
We must take care of the quality of life of the future generations as well as our’s.
We have to handle energy rationally which means;
· Economically and,
· Efficiently.
Fossil fuel:-
These are the proven energy reserves; real reserves may be up to a factor 4 larger. Significant uncertainty exists for these numbers. Estimating the remaining fossil fuels on the planet depends on a detailed understanding of the Earth's crust. While modern drilling technology makes it possible to drill wells in up to 3 km of water to verify the exact composition of the geology, one half of the ocean is deeper than 3 km, leaving about a third of the planet beyond the reach of detailed analysis.
In addition to uncertainty in real reserves, there is significant uncertainty in technological and economic factors that impact what percentage of reserves can be recovered gainfully. In general the easiest to reach deposits are the first extracted. Factors affecting the cost of exploiting the remaining reserves include the accessibility of fossil deposits, the level of sulfur and other pollutants in the oil and the coal, transportation costs, and societal instability in producing regions
Coal:-
Coal is the most abundant and burned fossil fuel. This was the fuel that launched the industrial revolution and has continued to grow in use; China, which already has many of the world's most polluted cities, was in 2007 building about two coal-fired power plants every week. Coal is the fastest growing fossil fuel and its large reserves would make it a popular candidate to meet the energy demand of the global community, short of global warming concerns and other pollutants. According to the International Energy Agency the proven reserves of coal are around 909 billion tonnes, which could sustain the current production rate for 155 years, although at a 5% growth per annum this would be reduced to 45 years, or until 2051. With the Fischer- Tropsch process it is possible to make liquid fuels such as diesel and jet fuel from coal. In the United States, 49% of electricity generation comes from burning coal.
Natural Gas:-
Natural gas is a widely available fossil fuel with estimated 850 000 km³ in recoverable reserves and at least that much more using enhanced methods to release shale gas. Improvements in technology and wide exploration led to a major increase in recoverable natural gas reserves as shale fracking methods were developed. At present usage rates, natural gas could supply most of the world's energy needs for between 100 and 250 years, depending on increase in consumption over time.
Oil:-
It is estimated that there may be 57 ZJ of oil reserves on Earth (although estimates vary from a low of 8 ZJ,[10] consisting of currently proven and recoverable reserves, to a maximum of 110 ZJ consisting of available, but not necessarily recoverable reserves, and including optimistic estimates for unconventional sources such as oil sands and oil shale. Current consensus among the 18 recognized estimates of supply profiles is that the peak of extraction will occur in 2020 at the rate of 93-million barrels per day (mbd). Current oil consumption is at the rate of 0.18 ZJ per year (31.1 billion barrels) or 85-mbd.
There is growing concern that peak oil production may be reached in the near future, resulting in severe oil price increases. A 2005 French Economics, Industry and Finance Ministry report suggested a worst-case scenario that could occur as early as 2013. There are also theories that peak of the global oil production may occur in as little as 2–3 years. The ASPO predicts peak year to be in 2010. Some other theories present the view that it has already taken place in 2005. World crude oil production (including lease condensates) according to US EIA data decreased from a peak of 73.720 mbd in 2005 to 73.437 in 2006, 72.981 in 2007, and 73.697 in 2008. According to peak oil theory, increasing production will lead to a more rapid collapse of production in the future, while decreasing production will lead to a slower decrease, as the bell-shaped curve will be spread out over more years.
In a stated goal of increasing oil prices to $75/barrel, which had fallen from a high of $147 to a low of $40, OPEC announced decreasing production by 2.2 mbd beginning 1 January 2009
Nuclear energy:-
The International Atomic Energy Agency estimates the remaining uranium resources to be equal to 2500 ZJ. This assumes the use of breeder reactors, which are able to create more fissile material than they consume. IPCC estimated currently proved economically recoverable uranium deposits for once-through fuel cycles reactors to be only 2 ZJ. The ultimately recoverable uranium is estimated to be 17 ZJ for once-through reactors and 1000 ZJ with reprocessing and fast breeder reactors.
Resources and technology do not constrain the capacity of nuclear power to contribute to meeting the energy demand for the 21st century. However, political and environmental concerns about nuclear safety and radioactive waste started to limit the growth of this energy supply at the end of last century, particularly due to a number of nuclear accidents. Concerns about nuclear proliferation (especially with plutonium produced by breeder reactors) mean that the development of nuclear power by countries such as Iran and Syria is being actively discouraged by the international community.
Although at the beginning of the 21st century uranium is the primary nuclear fuel worldwide, others such as thorium and hydrogen had been under investigation since the middle of the 20th century.
Thorium reserves significantly exceed those of uranium, and of course hydrogen is abundant. It is also considered by many to be easier to obtain than uranium. While uranium mines are enclosed underground and thus very dangerous for the miners, thorium is taken from open pits, and is estimated to be roughly three times as abundant as uranium in the Earth's crust.
Since the 1960s, numerous facilities throughout the world have burned Thorium.
Alternatives for energy production through fusion of hydrogen has been under investigation since the 1950s. No materials can withstand the temperatures required to ignite the fuel, so it must be confined by methods which use no materials. Magnetic and inertial confinement are the main alternatives (Cadarache, Inertial confinement fusion) both of which are hot research topics in the early years of the 21st century.
Fusion power is the process driving the sun and other stars. It generates large quantities of heat by fusing the nuclei of hydrogen or helium isotopes, which may be derived from seawater. The heat can theoretically be harnessed to generate electricity. The temperatures and pressures needed to sustain fusion make it a very difficult process to control. Fusion is theoretically able to supply vast quantities of energy, with relatively little pollution. Although both the United States and the European Union, along with other countries, are supporting fusion research (such as investing in the ITER facility), according to one report, inadequate research has stalled progress in fusion research for the past 20 years.
Renewable resources:-
Renewable resources are available each year, unlike non-renewable resources, which are eventually depleted. A simple comparison is a coal mine and a forest. While the forest could be depleted, if it is managed it represents a continuous supply of energy, vs. the coal mine, which once has been exhausted is gone. Most of earth's available energy resources are renewable resources. Renewable resources account for more than 93 percent of total U.S. energy reserves. Annual renewable resources were multiplied times thirty years for comparison with non-renewable resources. In other words, if all non-renewable resources were uniformly exhausted in 30 years, they would only account for 7 percent of available resources each year, if all available renewable resources were developed
Solar energy:-
Renewable energy sources are even larger than the traditional fossil fuels and in theory can easily supply the world's energy needs. 89 PW of solar power falls on the planet's surface. While it is not possible to capture all, or even most, of this energy, capturing less than 0.02% would be enough to meet the current energy needs. Barriers to further solar generation include the high price of making solar cells and reliance on weather patterns to generate electricity. Also, current solar generation does not produce electricity at night, which is a particular problem in high northern and southern latitude countries; energy demand is highest in winter, while availability of solar energy is lowest. This could be overcome by buying power from countries closer to the equator during winter months, and may also be addressed with technological developments such as the development of inexpensive energy storage. Globally, solar generation is the fastest growing source of energy, seeing an annual average growth of 35% over the past few years. Japan, Europe, China, U.S. and India are the major growing investors in solar energy. Solar power's share of worldwide electricity usage at the end of 2014 was 1%
The available wind energy estimates range from 300 TW to 870 TW. Using the lower estimate, just 5% of the available wind energy would supply the current worldwide energy needs. Most of this wind energy is available over the open ocean. The oceans cover 71% of the planet and wind tends to blow more strongly over open water because there are fewer obstructions.
At the end of 2005, 0.3 GW of electricity was produced by tidal power. Due to the tidal forces created by the Moon (68%) and the Sun (32%), and the Earth's relative rotation with respect to Moon and Sun, there are fluctuating tides. These tidal fluctuations result in dissipation at an average rate of about 3.7 TW.
Another physical limitation is the energy available in the tidal fluctuations of the oceans, which is about 0.6 EJ (exajoule).Note this is only a tiny fraction of the total rotational energy of the Earth. Without forcing, this energy would be dissipated (at a dissipation rate of 3.7 TW) in about four semi-diurnal tide periods. So, dissipation plays a significant role in the tidal dynamics of the oceans. Therefore, this limits the available tidal energy to around 0.8 TW (20% of the dissipation rate) in order not to disturb the tidal dynamics too much.
Waves are derived from wind, which is in turn derived from solar energy, and at each conversion there is a drop of about two orders of magnitude in available energy. The total power of waves that wash against our shores add up to 3 TW.
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