Energy Consumption as a Measure of Prosperity
Energy is an important input in all sectors of any country's economy. The standard of living of a given country can be directly related to per capita energy consumption.
Energy crisis is due to the two reasons; firstly, that the population of the world has increased rapidly and secondly the standard of living of human beings has increased.
If we take the annual per capita income of various countries and plot them against per head energy consumption, it will appear that the per capita energy consumption is a measure of the per capita income or the per capita energy consumption is a measure of the prosperity of the nation. As of March 2011, the per capita income of U.S.A is about $ 47000, and of Pakistan is $ 2700, i.e. 17 times more than per capita income of Pakistan. So also is the per capita energy consumption. The per capita energy consumption in U.S.A is 10381 kW per year, whereas the per capita energy consumption in Pakistan is 608 kW/year. U.S.A with 19.4% of world's population consumes 32% of the total energy consumed in the world, whereas India, a developing country with 17.3% of the world's population consumes only 1%, of the total energy consumed in the world. Therefore one might conclude that to be materially prosperous; a human being needs to consume more and more energy than his own. '
Developing countries, at present export primary products such as food, coffee, tea, jute and ores etc. This does not give them the full value of their resources. To get better value, the primary products should be processed to products for export. This needs energy. Assuming the, consumption of energy is estimated to be of 10 million megawatts by the year 2000 AD, this figure was estimated for 2005 as 17.42 Trillion Wh.
This assumes that the present pattern of consumption, in which the relative energy consumption of countries remain the same, i.e. the per capita energy in developed countries remain much more than in the developing countries. If the standard of living in the developing countries is improved and approaches that of the developed countries, the energy requirement in the world in the year 2011 A.D. will be much more than estimated above.
World Energy Futures
If present trend continues, the world in the year 2011 AD will be more crowded than that of today. The world population may reach 7 billion by 2012 AD. The conventional sources of energy are depleting and may be exhausted by the end of the century or beginning of the next century. Nuclear energy requires skilled technicians and poses the safety as regards to radioactive waste disposal. Solar energy and other non-conventional energy sources, are the sources, those are to be utilized in future.
Conclusions of the study on alternate energy strategies are:
1. The supply of oil will fail to meet increasing demand before the year 2000, even if energy prices rise 50 per cent above current levels in real terms. Additional constrains on oil production will hasten this shortage, thereby reducing the time available for action on alternatives.
2. Demand for energy will continue to grow even if governments adopt vigorous policies to conserve energy. This growth must increasingly be satisfied by energy resources other than oil, which will be progressively reserved for uses that oil can satisfy.
3. The continued growth of energy demand requires that energy resources be developed with the utmost vigor. The change from a world economy dominated by oil must start now. The alternatives require 5 to 15 years to develop, and the need for replacement fuels will increase rapidly as the last decade of the century is approached.
4. Electricity from nuclear power is capable of making an important contribution to the global energy supply although worldwide acceptance of it, on a sufficiently large scale yet to be established. Fusion power will not be significant before the year 2020. See note below.
[Using the most powerful laser system ever built, scientists have brought us one step closer to nuclear fusion power, a new study says.
The same process that powers our sun and other stars, nuclear fusion has the potential to be an efficient, carbon-free energy source—with none of the radioactive waste associated with the nuclear fission method used in current nuclear plants.
Thanks to the new achievement, a prototype nuclear fusion power plant could be operating within a decade, speculated study leader Siegfried Glenzer, a physicist at
Lawrence Livermore National Laboratory in California.]
5. Coal has the potential to contribute substantially to future energy supplies. Coal reserves are abundant, but taking advantage of them requires an active programme of development by both producers and consumers.
6. Natural gas reserves are large enough to meet projected demand provided the incentives are sufficient to encourage the development of extensive and costly inter continental gas transportation systems.
7. Although the resource base of other fossil fuels such as oils sands, heavy oil and oil shale is very large, they are likely to supply only small amounts of energy.
8. Other than hydroelectric power, renewable resources of energy e.g., solar, wind, wave are unlikely to contribute significant quantities of additional energy during the century at the global level, although they could be of importance in particular areas. They are likely to become increasingly important in the 21st century.
9. Energy efficiency improvements, beyond the substantial energy conservation assumptions already built into our analysis, can further reduce energy demand and narrow the prospective gaps between energy demand and supply. Policies for achieving energy conservation should continue to be key elements of all future energy strategies.
It was concluded that world oil production if likely to level off-very shortly and that alternative fuels will have to be meet growing energy demand. Large investments and long lead times are required to produce these fuels on a scale large enough to fill the prospective shortage of oil, the fuel that now furnishes most of the world's energy. The task for the world will be to manage a transition from dependence on oil to greater reliance on other fossil fuels, nuclear energy and later, renewable energy system.
Energy Sources and their Availability
Introduction.
Today, every country draws its energy needs from a variety of sources. We can broadly categorize these sources as commercial and noncommercial. The commercial sources include the fossil fuels (coal, oil and natural gas), hydroelectric power and nuclear power, while the non-commercial sources include wood, animal waste tend agricultural wastes. In an industrialized country like, U.S.A., most of the energy requirements are met from commercial sources, while in an industrially less developed country the use of commercial an non-commercial sources are about equal.
Commercial or Conventional Energy Sources
Major Sources of energy include:
(1) Fossil fuels i.e. solid fuels (mainly coal including anthracite, bituminous, and brown coals lignits and peats), liquid and gaseous fuels including petroleum and its derivatives and natural gas.
(2) Water power or energy stored in water.
(3) Energy of nuclear fission.
Minor sources of energy include sun, wind, tides in the sea, geothermal, ocean thermal electric conversion, fuel cells, thermionic, thermoelectric generators etc.
Wood was dominant source of energy in the pre-industrialization era. It gave way to coal and coke. Use of coal reached a peak in the early part of the twentieth century. Oil got introduced at that time and has taken a substantial share from wood and coal. Wood is no more regarded as a conventional source. Hydroelectricity has already grown to a stable level in most of the developed countries. A brief account of the various important sources of energy and their future possibilities is given below.
The percentage use of various sources for the total energy consumption in the world is given in the chart below:
Coal, oil, gas, uranium and hydro are commonly known as commercial or conventional energy sources. Looking at the percentage distribution one finds that world's energy supply comes mainly from fossil fuels. The heavy dependence on fossil fuels stands out clearly. One of the so most significant aspects of the current energy consumption pattern in many developing countries is that non-commercial sources such as firewood, animal dung and agricultural waste represent a significant 8% of the total energy used in the world. These constitute about 4 times the energy produced by the hydro and 60 times the energy produced by nuclear sources.
In some developing countries non-commercial energy sources are a significant fraction of the total resources. This dependence of the developing countries is likely to continue unless replaced by other alternative sources of energy.
Coal.
Since the advent of industrialization coal has been the most common source of energy. In the last three decades, the world switched over from coal to oil as a major source of energy because it is simpler and cleaner to obtain useful energy £rom oil.
Modern steam boilers burn coal in any of its forms as a primary fuel. Coal developed from vegetable matter which grew in past geological ages. Trees and plants falling into water decayed and produced peat bogs. Gigantic geological upheavals burried these bogs under layers of silt. Soil pressure, heat and movement of the earth's crust distilled off some of the bog's gaseous matter to form brown coal, or lignite. Continuing subterranean activity reduces the coal's gaseous content progressively to form different ranks ; peat lignite, bituminous and anthracite.
According to estimates coal is abundant. It is enough to last for 200 years. However, it is low in calorific value and its shipping is expensive. Coal is pollutant and when burnt it produces CO2 and CO. Extensive use of coal as a source of energy is likely to disturb the ecological balance of CO2 since vegetations in the world would not be capable of absorbing such large proportions of carbon dioxide produced by burning large quantities of coal.
Oil. Almost 40% of the energy needs of the world are fed by oil.
The rising prices of oil has brought a considerable strain to the economy of the world more, so in the case of the developing countries that do not possess oil reserves enough for their own consumption. With today's consumption and a resource amount of 250,000 million tones of oil, it would suffice for about 100 years unless more oil is discovered. The question is whether an alternative to oil would then be available; the world must start thinking of a change from a world economy dominated by oil.
Refining petroleum or crude oil produces our fuel oils.
Gas. Gas is incompletely utilized at present and huge quantities are burnt off in the oil production process because of the non availability of ready market.
The reason may be the high transportation cost of the gas. To transport gas is costlier than transporting oil. Large reserves are estimated to be located in inaccessible areas.
Gaseous fuels can be classified as :
(1) Gases of fixed composition such as acetylene, ethylene, methane etc.
(2) Composite industrial gases such as producer gas, coke oven gas, water gas, blast furnace gas etc.
Agriculture and organic wastes.
At present small quantities of agricultural and organic wastes consisting of draw saw dust, bagasse, garbage, animal dung, paddy husk and corn stem accounting a major energy consumption. Most of the remaining material was burnt or left, unused causing considerable environmental problems.
1. The waste should be utilized near the source, in order to reduce the transportation cost.
2. Appropriate equipments for burning, or extracting energy from the materials should be developed to suit the local conditions and meet the requirements of the rural areas.
3. Other non energy uses of the material should also be considered.
Considering the availability and the location of material produced, these resources are regarded as an important energy supply for the rural areas in the near future.
Water Power.
Waterpower is developed by allowing water to fall under the force of gravity. It is used almost exclusively for electric power generation. In fact, the generation of water power on a large scale became possible around the beginning of the twentieth century only with the development of electrical power transmission. Prior to that, water power plants (Hydroelectric plants) were usually of small capacities usual less than 100 kW.
Potential energy of water is converted into mechanical energy by using prime moves known as hydraulic turbines.
Water power is quite cheap where water is available in abundance. Although capital cost of hydroelectric power plants is higher as compared to other types of power plants but their operating costs are quite low, as no fuel is required in this case.
Hydro-electric power is one of the indirect ways in which solar energy is being used. Thus, the main factor in its favor is that it is the only renewable non-depleting source of the present commercial sources.
In addition it does not create any pollution problem. The development rate of hydropower is still low, due to the following problems.
1. In developing a project, it will take about 6-10 years time for planning, investigation and construction.
2. High capital investment is needed, and some parts of the investment have to be derived from foreign sources.
3. There are growing problems on relocation of villages involved, compensation for damage, selecting the suitable resettlement area and environmental impact.
Because of long transmission line to the villages with low load factor, the electric power will be available to the people in rural areas may not be economical and the setting up of isolated diesel generation plants will also experience high losses with the existing electric tariff rates. This leads to the development of mini or micro hydro electric projects to supply the electric power to remote areas. These projects may operate as isolated systems or connected to the main grid where it is feasible.
The importance or micro hydroelectric projects have been observed in some parts of the country with availability of river flow throughout the year with a possibility of medium to higher head development. In order to reduce the cost of development to the acceptaole figure, several measures have been considered as follows:
(a) Development of low cost turbines and generators.
(b) Participation of villages in the development and operation of the project.
(c) Using the appropriate technology and tolerable substandard requirement and project civil work component at the beginning stage.
Food for more thought: A map & a picture is worth more than a thousand words:
Nuclear Power.
According to modern theories of atomic structure, matter consists at minute particles known as atoms. These atoms represent enormous concentration of binding energy. Controlled fission of heavier unstable atoms such as U235, Th232 and artificial element Pu239, liberate large. amount of heat energy. This enormous release of energy from a relatively small mass of nuclear fuels makes this source of energy of great importance. The energy released by the complete fission of one kg of U235, is equal to the heat energy obtained by burning 4500 tonnes of high grade coal or 2200 tons of oil. The heat produced by nuclear fission of the atoms of fissionable -material is utilized in special heat exchangers for the production of steam which is then used to drive turbo generators as in the conventional power plants.
However there are some limitations in the use of nuclear energy namely high capital cost of nuclear power plants, limited availability of raw materials, difficulties associated with disposal of radioactive waste, and shortage of well trained personnel to handle the nuclear power plants.
The uranium reserves in the world at present are small. These reserves are recoverable but are expensive. Further it is estimated that uranium reserves have only 3% of the energy contained in the oil reserves. A country like France produces about 30% of its total energy by nuclear methods, whereas a country like India has uranium sufficient enough only to produce 6 x 106 kW, a mere 1 % of its current energy requirements.
Development of fast breeder reactor, which is not yet free from technical difficulties, will decide the future of nuclear power. Controlled fusion may also add brighter prospects to the use of nuclear energy.
Nuclear power is having considerable potential. In countries like France and Belgium, it is contributing to the extent of 70 percent and 58 percent to the overall power generated.
Three systems are considered for nuclear power generation. The first is based on natural uranium yielding power and plutonium. The second employs fast breeder reactor using plutonium and depleted uranium. The third is by fast breeder reactor using thorium and converting it to uranium.
The first method alone has been commercialized ,and the other methods may take some more time for large scale use. A number of scientific and technological hurdles have to be crossed till the stage of thorium-based fast breeder reactor is reached. Design and indigenous fabrication capabilities have also to be achieved.
The Nuclear option.
One response to the problem of increasing fossil fuel dependency has been to advocate a rapid expansion of nuclear power. However, even if thousands of large nuclear reactors could be built over the coming decades, nuclear power would still only make a small contribution to meeting world energy demand. After more than a quarter of a century of development, nuclear power provides only a few percent of the world's electricity which itself only accounts for a small proportion of the total energy demand. Furthermore, the nuclear path is fraught with dangers. The intractable nature of many of the environmental as well as the social, political and technical problems, and the continued escalation in the costs, have led to widespread disenchantment with nuclear technology.
It is sometimes suggested that nuclear fusion has better prospects, but this may be as much wishful thinking as the early dreams of atomic electricity too cheap to be worth metering. Nuclear fusion is fundamentally different from nuclear fission; it involves fusing together of light atoms rather than the breaking apart of heavy ones.
To ignite and sustain a fusion reaction between say, Deuterium and Tritium (two forms of hydrogen), it would be necessary to heat the fuel to a temperature in excess of 100 million degree centigrade-hotter than the sun-and to confine the resulting plasma for sufficient time to be able to extract useful amount of energy. Even if this daunting problem can be solved, the cost of the machinery that will be required is likely to make fusion wholly uneconomic.
Guess why high speed train system SNCF is possible in France, and in some other
countries ?
Emerging Energy Technologies. Next!
