Introduction:
The modern United States economy relies on fossil fuels for up to 82% of the overall energy supply. This energy supports industrial processes, commercial and residential, and transportation purposes. Oil accounts for 34% of the overall energy demand, coal accounts for 39%, natural gas represents 27%, hydropower accounts for 7%, while nuclear energy accounts for 19% (United States Energy Department, 33). However, in terms of net energy consumption, fossil fuels accounted for 67.5% while other energy sources; that is, nuclear and other renewable energy sources, such as hydro-power and wind-energy accounted for 32.5% in 2013 (United States Energy Department, 33).
In the conversion and subsequent use of these fuels into energy-producing elements, each of the fuels has merits and demerits. This report shall focus on the environmental concerns arising from each of the aforementioned fuels and how their use influence other decisions entailing plant design, operations and cost. Therefore, the economic costs of a distinct fuel increase with its decrease in efficiency (United States Climate Action Report 59).
The use of coal in the United States dates back in the 1880s, and its use has continued to be up to the modern day. In 2013, coal accounted for 39 percent of the total energy demands. However, coal has been documented as the dirtiest among all fuels due to its substantial emissions, which negatively affects the environment. The thick soot, laden with sulphur dioxide and carbon dioxide effluents, results to acidic rain that cause considerable damage to plants, animals, buildings, and infrastructure. In addition, coal-fired industrial processes have been studied to yield up-to 13 percent of the mercury produced from human activity (United States Energy Department 41).
Several technological processes have been available among the coal-processing plants to alleviate adverse effects from coal, such as greenhouse effect and global warming. For example, the pre-combustion capture is a gasification process that efficiently removes nitrogen, sulphur, and excess carbon dioxide. These are the main gases associated with global warming and ultimate climate change (United States Climate Action Report 85).
The purification cost subjects the energy sector into collateral economic costs, such as installation of fuel cells and other hybrid systems. The gasification process is expensive, and it is yet to be proven. Critics to the concept highlight that despite the resulting 70 percent energy efficiency, the technology remains invalid as long as the gases are released into the atmosphere.
Natural gas:
Natural gas is a fuel made from carbon and hydrogen and is combusted to generate electricity. In addition, the gas is gaining wide-usage in motor vehicles with over 142, 000 natural gas-powered vehicles on the American roads. Upon combustion, the fuel emits methane, nitrogen, and carbon oxides, which are the principal gases accelerating global warming and climate change.
Compared to coal-based fuels, natural gas produces about half of the emissions produced by coal (United States Energy Department 49). In addition, the water used in combustion is eventually released into rivers, which results to thermal pollution. The intense heat destroys most of the aquatic life. Toxic metals such as lead and mercury also end up in the water resulting to blood poisoning.
As an intervention against the adverse, the federal government introduced the carbon-tax rate system, which creates a market price for greenhouse gases emission. All power plants ought to ratify such tax systems on an annual basis, and thus accelerating their industrial operation costs. The concept is based on the assumption that power plants shall limit their emissions to a level that becomes cheap or affordable and successively reduce the emission. Companies are increasingly adopting the natural gas generator technology to produce cleaner natural gas, with lessened environmental impacts, which can convert gases such as propane into natural gas.
Nuclear energy:
As compared to other energy alternatives, nuclear energy offers environmental benefits since it does not contribute to greenhouse gases emission, such as the sulphur and carbon dioxides. Nonetheless, the cumulative effects from nuclear wastes rise above the wastes from other fossil fuels. The wastes are in the form of solid wastes, process chemicals, spent fuel, and intensely heated cooling water.
The solid waste is radioactive in nature, which causes blood poisoning, mutations and growth of cancerous tissues in animals and human as well as systemic damage to plants. When the heated cooling water is discharged into rivers and other water sources, there is a drastic increase in temperature, which results to death of aquatic life, mainly from burns and oxygen deprivation (United States Climate Action Report 68).
In mitigating against the damaging effects, the process of energy generation has its focus on appropriate disposal of the solid wastes. The procedures entail recycling of spent fuels; that is, reprocessing them into less injurious components. In addition, the wastes are buried in specialized trenches. The reprocessing and burying procedures are very expensive, and this has prompted the United States government to affix an extra cost of 0.1 cents per kilowatt-hour of power generated.
The ultimate waste disposal and reprocessing capital-intensive systems render the energy source expensive considering the high operating costs involved in the processing of nuclear energy. Consequently, many power plants are entreating the government for economic subsidies (United States Energy Department 73).
Hydroelectricity:
Hydropower is one form of the of the renewable energy sources. The power is dependent on water availability and changes in elevation; high availability and water levels are essential in adequate power generation. Though hydropower has no air-contaminating attributes, its mechanical construction interferes with the ecological functionality of aquatic ecosystems (National Renewable Energy Laboratory 12).
Compared to other energy sources, hydropower prevails as the most cost-effective form of energy. The power source eliminates the greenhouse gas emissions or radioactive wastes, and rids-off hazards arising from gas and coal mining. Moreover, hydroelectric plants have a predictable load factor that relies on a constant water reservoir.
Conclusion:
The use of conventional fossil fuels to meet energy demands, which is widely used, has progressively yielded to widespread environmental degradation. The damage has seen to the loss of both plant and animal species as well as interfering with the natural functionality of the ecosystems where these species exist.
Consequently, companies have continued to adopt the technology in alleviating the injurious effects, which has in return accelerated the operation costs of the power plants. However, with renewable energy sources, such as hydropower, it is vivid that the overhead costs in industrial redesigns and waste management can be lessened (National Renewable Energy Laboratory 27).
Works cited:
United States Energy Department, Las Vegas Valley Public Land and Tule Springs Fossil Beds National Monument: Report (to Accompany S. 974). , 2014. Internet resource.
National Renewable Energy Laboratory (NREL). Renewable Electricity Futures Study. , 2012. Print.
United States Climate Action Report 2014: First Biennial Report of the United States of America: Sixth National Communication of the United States of America under the United Nations Framework Convention on Climate Change. , 2014. Internet resource.
