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Energy development

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Energy development [[is the ongoing effort to provide sustainable energy resources through knowledge, skills, and constructions. When harnessing energy from primary energy sources and converting them into more convenient secondary energy forms, such as electrical energy and cleaner fuel, both emissions (reducing pollution) and quality (more efficient use) are important.

Higher electricity use per capita correlates with a higher score on the Human Development Index(1997). Developing nations score much lower on these variables than developed nations. The continued rapid economic growth and increase in living standards in developing nations with large populations, like China and India, is dependent on a rapid and large expansion of energy production capacity.
Higher electricity use per capita correlates with a higher score on the Human Development Index(1997). Developing nations score much lower on these variables than developed nations. The continued rapid economic growth and increase in living standards in developing nations with large populations, like China and India, is dependent on a rapid and large expansion of energy production capacity.

Contents

Dependence on external energy sources

Technologically advanced societies have become increasingly dependent on external energy sources for transportation, the production of many manufactured goods, and the delivery of energy services. This energy allows people, in general, to live under otherwise unfavorable climatic conditions through the use of heating, ventilation, and/or air conditioning. Level of use of external energy sources differs across societies, as do the climate, convenience, traffic congestion, pollution, production, and greenhouse gas emissions of each society.

Increased levels of human comfort generally induce increased dependence on external energy sources, although the application of energy efficiency and conservation approaches allows a certain degree of mitigation of the dependence. Wise energy use therefore embodies the idea of balancing human comfort with reasonable energy consumption levels by researching and implementing effective and sustainable energy harvesting and utilization measures.

Limitations to energy development

A key limit to the development of any particular energy source is availability of the underlying resource. Most of the world's main energy sources are based on the consumption of non-renewable resources (petroleum, coal, natural gas, and uranium). While still a small segment of the energy supply, renewable sources such as wind power and solar power are growing rapidly in market share.

Closely linked to energy development are concerns about the possible environmental effects of energy use, such as climate changes. Energy development issues are part of the much debated sustainable development problem.

Primary energy sources

Primary energy sources are substances or processes with concentrations of energy at a high enough potential to be feasibly encouraged to convert to lower energy forms under human control for human benefit. Except for nuclear fuels, tidal energy and geothermal energy, all terrestrial energy sources are from current solar insolation or from fossil remains of plant and animal life that relied directly and indirectly upon sunlight, respectively. And ultimately, solar energy itself is the result of the Sun's nuclear fusion. Geothermal power from hot, hardened rock above the magma of the earth's core is the result of the accumulation of radioactive materials during the formation of Earth which was the byproduct of a previous supernova event.

Fossil fuels

Main article: Fossil fuel

Fossil fuels, in terms of energy, involve the burning of 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.

Pros

  • The technology and infrastructure already exist for the use of fossil fuels, (although oil and natural gas are approaching peak production, and will require a transition to other fuels and/or other measures).
  • Commonly-used fossil fuels in liquid form such as light crude oil, gasoline, and LPG are easy to distribute.

Cons

  • Petroleum-powered vehicles are very inefficient. Only about 15% of the energy from the fuel they consume is converted into useful motion.[1] The rest of the fuel-source energy is inefficiently expended as waste heat. The heat and gaseous pollution emissions harm our environment.
    • The inefficient atmospheric combustion (burning) of fossil fuels in vehicles, buildings, and power plants contributes to urban heat islands,[2] which contribute to overall global warming.
      • The combustion of fossil fuels leads to the release of pollution into the atmosphere. According to the Union of Concerned Scientists, a typical coal plant produces in one year:[3]
          • 3,700,000 tons of carbon dioxide (CO2), the primary cause of global warming.
          • 10,000 tons of sulfur dioxide (SO2), the leading cause of acid rain.
          • 500 tons of small airborne particles, which result in chronic bronchitis, aggravated asthma, and premature death, in addition to haze-obstructed visibility.
          • 10,200 tons of nitrogen oxides (NOx), (from high-temperature atmospheric combustion), leading to formation of ozone (smog) which inflames the lungs, burning lung tissue making people more susceptible to respiratory illness.
          • 720 tons of carbon monoxide (CO), resulting in headaches and additional stress on people with heart disease.
          • 220 tons of hydrocarbons, toxic volatile organic compounds (VOC), which form ozone.
          • 170 pounds of mercury, where just 1/70th of a teaspoon deposited on a 25-acre lake can make the fish unsafe to eat.
          • 225 pounds of arsenic, which will cause cancer in one out of 100 people who drink water containing 50 parts per billion.
          • 114 pounds of lead, 4 pounds of cadmium, other toxic heavy metals, and trace amounts of uranium.
        • Dependence on fossil fuels from volatile regions or countries creates energy security risks for dependent countries. Oil dependence in particular has led to war, major funding of radical terrorists, monopolization, and socio-political instability.
        • Fossil fuels are non-renewable, un-sustainable resources, which will eventually decline in production[4] and become exhausted, with dire consequences to societies that remain highly dependent on them. (Fossil fuels are actually slowly forming continuously, but we are using them up at a rate approximately 100,000 times faster than they are formed.)
          Image:Moss Landing Power Plant p1270026.jpg
          The Moss Landing Power Plant burns natural gas to produce electricity in California.
          • Extracting fossil fuels is becoming more difficult as we consume the most accessible fuel deposits. Extraction of fossil fuels is becoming more expensive and more dangerous as mines get deeper and oil rigs must drill deeper, and go further out to sea.[5]
            Gas flare from an oil refinery.
            Gas flare from an oil refinery.

            Since these power plants are thermal engines, and are typically quite large, waste heat disposal becomes an issue at high ambient temperature. Thus, at a time of peak demand, a power plant may need to be shut down or operate at a reduced power level, as sometimes do nuclear power plants, for the same reasons.

            Biomass, biofuels, and vegetable oil

            Sugar cane residue can be used as a biofuel
            Sugar cane residue can be used as a biofuel
            Main articles: Alcohol fuel, Biomass, Vegetable oil economy, vegetable oil as fuel, biodiesel, Ethanol fuel

            Biomass production involves using garbage or other renewable resources such as corn or other vegetation, to generate electricity. When garbage decomposes the methane produced is captured in pipes and later burned to produce electricity. Vegetation and wood can be burned directly, like fossil fuels, to generate energy, or processed to form alcohols.

            Vegetable oil is generated from sunlight and CO2 by plants. It is safer to use and store than gasoline or diesel as it has a higher flash point. Straight vegetable oil works in diesel engines if it is heated first. Vegetable oil can also be transesterified to make biodiesel which burns like normal diesel.

            Pros

            • Biomass production can be used to burn organic waste products resulting from agriculture. This type of recycling encourages the philosophy that nothing on this Earth should be wasted. The result is less demand on the Earth's resources, and a higher carrying capacity for Earth because non-renewable fossil fuels are not consumed.
            • Biomass is abundant on Earth and is generally renewable. In theory, we will never run out of organic waste products as fuel, because we are continuously producing them. In addition, biomass is found throughout the world, a fact that should alleviate energy pressures in third world nations.
            • When methods of biomass production other than direct combustion of plant mass, such as fermentation and pyrolysis, are used, there is little effect on the environment. Alcohols and other fuels produced by these alternative methods are clean burning and are feasible replacements to fossil fuels.
            • Since CO2 is first taken out of the atmosphere to make the vegetable oil and then put back after it is burned in the engine, there is no net increase in CO2. So vegetable oil does not contribute to the problem of greenhouse gas.
            • Vegetable oil has a higher flash point and is safer than most fossil fuels.
            • Transitioning to vegetable oil could be relatively easy as biodiesel works where diesel works, and straight vegetable oil takes relatively minor modifications.
            • The World already produces more than 100 billion gallons a year for food industry, so we have experience making it.
            • Algaculture has the potential to produce far more vegetable oil per acre than current plants.
            • Infrastructure for biodiesel around the World is significant and growing.

            Cons

            • Direct combustion of any carbon-based fuel without emission filtering generally leads to air pollution similar to that from fossil fuels.
            • Some researchers claim that, when biomass crops are the product of intensive farming, ethanol fuel production results in a net loss of energy after one accounts for the fuel costs of petroleum-and-natural-gas fertilizer production, farm equipment, and the distillation process.[6]
              • There is a long list of reasons why even non-food-based cellulosic ethanol cannot solve our energy crisis or global warming problems.[7]
                • Direct competition with land use for food production.
                • Current production methods would require enormous amounts of land to replace all gasoline and diesel. With current technology, it is not feasible for biofuels to replace the demand for petroleum.
                • Even with the most-optimistic energy return on investment claims, in order to use 100% solar energy to grow corn and produce ethanol (fueling machinery with ethanol, distilling with heat from burning crop residues, using NO fossil fuels at all), the consumption of ethanol to replace only the current U.S. petroleum use would require three quarters of all the cultivated land on the face of the Earth.[8]

                  Hydroelectric energy

                  Main article: Hydroelectricity

                  In hydro energy, the gravitational descent of a river is compressed from a long run to a single location with a dam or a flume. This creates a location where concentrated pressure and flow can be used to turn turbines or water wheels, which drive a mechanical mill or an electric generator.

                  Pros

                  • Hydroelectric power stations can promptly increase to full capacity, unlike other types of power stations. This is because water can be accumulated above the dam and released to coincide with peak demand.
                  • Electricity can be generated constantly, so long as sufficient water is available.
                  • Hydroelectric power produces no primary waste or pollution.
                  • Hydropower is a renewable resource.
                  • Hydroelectricity assists in securing a country's access to energy supplies.

                  Cons

                  • The construction of a dam can have a serious environmental impact on the surrounding areas. The amount and the quality of water downstream can be affected, which affects plant life both aquatic, and land-based. Because a river valley is being flooded, the delicate local habitat of many species are destroyed, while people living nearby may have to relocate their homes.
                  • Hydroelectricity can only be used in areas where there is a sufficient supply of water.
                  • Flooding submerges large forests (if they have not been harvested). The resulting anaerobic decomposition of the carboniferous materials releases methane, a greenhouse gas.
                  • Dams can contain huge amounts of water. As with every energy storage system, failure of containment can lead to catastrophic results, e.g. flooding.
                  • Hydroelectric plants rarely can be erected near load centres, requiring large transmission lines.

                  Tidal Power Generation

                  Main article: Tidal power

                  Tidal power can be extracted from Moon-gravity-powered tides by locating a water turbine in a tidal current, or by building impoundment pond dams that admit-or-release water through a turbine. The turbine can turn an electrical generator, or a gas compressor, that can then store energy until needed. Coastal tides are a source of clean, free, renewable, sustainable energy.

                  Nuclear energy

                  Main article: Nuclear power
                  Image:Diablo canyon nuclear power plant.jpg
                  Diablo Canyon Power Plant Nuclear power station.
                  Image:Nuclear power stations.png
                  The status of nuclear power globally. Nations in dark green have reactors and are constructing new reactors, those in light green are constructing their first reactor, those in dark yellow are considering new reactors, those in light yellow are considering their first reactor, those in blue have reactors but are not constructing or decommissioning, those in light blue are considering decommissioning and those in red have decommissioned all their commercial reactors. Brown indicates that the country has declared itself free of nuclear power and weapons.
                  Image:Nuclear Power History.png
                  History of the use of nuclear power (top) and the number of active nuclear power plants (bottom).

                  Nuclear power stations use nuclear fission to generate energy by the reaction of uranium-235 inside a nuclear reactor. The reactor uses uranium rods, the atoms of which are split in the process of fission, releasing a large amount of energy. The process continues as a chain reaction with other nuclei. The heat released, heats water to create steam, which spins a turbine generator, producing electricity.

                  Depending on the type of fission fuel considered, estimates for existing supply at known usage rates varies from several decades for the currently popular Uranium-235 to thousands of years for uranium-238. At the present use rate, there are (as of 2007) about 70 years left of known uranium-235 reserves economically recoverable at an uranium price of US$ 130/kg.[9] The nuclear industry argue that the cost of fuel is a minor cost factor for fission power, more expensive, more difficult to extract sources of uranium could be used in the future, such as lower-grade ores, and if prices increased enough, from sources such as granite and seawater.[9] Increasing the price of uranium would have little effect on the overall cost of nuclear power; a doubling in the cost of natural uranium would increase the total cost of nuclear power by 5 percent. On the other hand, if the price of natural gas was doubled, the cost of gas-fired power would increase by about 60 percent.[10]

                  Opponents on the other hand argue that the correlation between price and production is not linear, but as the ores' concentration is becoming smaller, the difficulty (energy and resource consumption are increasing, while the yields are decreasing) of extraction is rising very fast, and that the assertion that a hear price will yield more uranium is overly optimistic; for example a rough estimate predicts that the extraction of uranium from granite will consume at least 70 times more energy than what it will produce in a reactor. As many as eleven countries have depleted their uranium resources, and only Canada has mines left which produce better than 1% concentration ore.[11] Seawater seems to be equally dubious as a source.[12] As a consequence an eventual doubling in the price of uranium will give a marginal increase in the volumes that are being produced.

                  Another alternative would be to use thorium as fission fuel. Thorium is three times more abundant in Earth's crust than uranium,[13] and much more of the thorium can be used (or, more precisely, converted into Uranium-233 and then used).

                  Current light water reactors burn the nuclear fuel poorly, leading to energy waste. Nuclear reprocessing[14] or burning the fuel better using different reactor designs would reduce the amount of waste material generated and allow better use of the available resources. As opposed to current light water reactors which use uranium-235 (0.7 percent of all natural uranium), fast breeder reactors convert the more abundant uranium-238 (99.3 percent of all natural uranium) into plutonium for fuel. It has been estimated that there is anywhere from 10,000 to five billion years worth of Uranium-238 for use in these power plants.[15] Breeder technology has been used in several reactors. However, the breeder reactors at Dounreay in Scotland, Monju in Japan and the Superphénix at Creys-Malville in France, in particular, have all had difficulties and were not economically competitive and have been decommissioned. The People's Republic of China intends to build breeders.[16]

                  The possibility of nuclear meltdowns and other reactor accidents, such as the Three Mile Island accident and the Chernobyl disaster, have caused much public fear. Research is being done to lessen the known problems of current reactor technology by developing automated and passively-safe reactors. Historically, however, coal and hydropower power generation have both been the cause of more deaths per energy unit produced than nuclear power generation.[17][18] Various kinds of energy infrastructure might be attacked by terrorists, including nuclear power plants, hydropower plants, and liquified natural gas tankers. Nuclear proliferation is the spread from nation to nation of nuclear technology, including nuclear power plants but especially nuclear weapons. New technology like SSTAR ("small, sealed, transportable, autonomous reactor") may lessen this risk.

                  The long-term radioactive waste storage problems of nuclear power have not been fully solved. Several countries have considered using underground repositories. Nuclear waste takes up little space compared to wastes from the chemical industry which remain toxic indefinitely.[14] Spent fuel rods are now stored in concrete casks close to the nuclear reactors.[19] The amounts of waste could be reduced in several ways. Both nuclear reprocessing and fast breeder reactors could reduce the amounts of waste. Subcritical reactors or fusion reactors could greatly reduce the time the waste has to be stored.[20] Subcritical reactors may also be able to do the same to already existing waste. The only way of dealing with waste today is by geological storage.

                  The economics of nuclear power is not simple to evaluate, because of high capital costs for building and very low fuel costs. Comparison with other power generation methods is strongly dependent on assumptions about construction timescales and capital financing for nuclear plants. See Economics of new nuclear power plants.

                  Depending on the source different energy return on energy investment (EROI) are claimed. Advocates (using life cycle analysis) argue that it takes 4–5 months of energy production from the nuclear plant to fully pay back the initial energy investment.[21] Opponents claim that it depends on the grades of the ores the fuel came from, so a full payback can vary from 10 to 18 years, and that the advocates' claim was based on the assumption of high grade ores (the yields are getting worst, as the ores are leaner, for less than 0.02% ores,the yield is less then 50%).[22]

                  Advocates also claim that it is possible to relatively rapidly increase the number of plants. Typical new reactor designs have a construction time of three to four years.[23] In 1983, 43 plants were being built, before an unexpected fall in fossil fuel prices stopped most new construction. Developing countries like India and China are rapidly increasing their nuclear energy use.[24][25] However, a Council on Foreign Relations report on nuclear energy argues that a rapid expansion of nuclear power may create shortages in building materials such as reactor-quality concrete and steel, skilled workers and engineers, and safety controls by skilled inspectors. This would drive up current prices.[26]

                  Pros

                  • The cost of making nuclear power, with current legislation, is about the same as making coal power, which is considered very inexpensive (see Economics of new nuclear power plants). If a carbon tax is applied, nuclear does not have to pay anything because nuclear does not emit toxic gases such as CO2, NO, CO, SO2, arsenic, etc. that are emitted by coal power plants.
                  • Because of the fear of a nuclear disaster, nuclear safety has become a major issue.
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