Advantages And Disadvantages Of Ethanol And Biodiesel Environmental Sciences Essay

Advantages And Disadvantages Of fermentation alcohol And Bio diesel engine Environmental Sciences EssayThe creations zero function has been increasing progressively since the industrial revolution 1. Global community is continuing to dramatically rise and the increase in economic development, particularly in China and India, over recent decades has contributed to increases in energy consumption 2. Currently, nearly 45 portion of Australias total energy consumption is bank noteed for by coal, with oil providing approximately 35 percent, congenital gas supplying approximately 15 percent and green power providing just over 5 percent 2. secondary give the axes ar stated to be a potentially viable preference to the expenditure of dodo enkindles. Fossil open fires contribute to some eighty percent of the total energy employmentd in the world 3, 4. Fossil fuels ar non-renewable resources that atomic frame 18 particular(a) in their supply and the keen of fossil f uels on a global scale contribute wee air pollution, such(prenominal) as nitrogen oxides (NOx), release signifi sewert amounts of greenhouse gases, such as hundred dioxide (CO2), and contribute to global warming 1, 3, 5, 6. alternate fuels are numbered to do a less adverse effect on the environment, and are stated to be a solution to the problems pretendd by fossil fuels 1. The main difference in the midst of fossil derived fuels and election fuels is the oxygen content, with election fuels having 10-45 wt% oxygen compared to fossil fuels which contain almost none 7. In Australia, the alternative fuels industry is relatively small, but is gradually expanding particularly in postulate to neutral spirits or biodiesel exertion8. Alternative fuels, such as ethanol and biodiesel whitethorn prospectively provide an alternative for global fuel requirements. at that place are however, a number of drawbacks related to alternative fuels which may inhibit them from complet ely switch fossil fuels without technological or genetic advancements 9.OutlineThis paper aims to come across the advantages and disadvantages of alternative fuels. The discussion allow for commence by defining alternative fuels and a number of relevant terms. The analysis will then consider ethanol as an alternative fuel and an overview of ethanol ware. Subsequently, biodiesels and an overview of biodiesel production will be examined. Following this, the advantages and disadvantages of alternative fuels will be considered. Lastly, the main arguments of this account will be summarised.DefinitionsAlternative fuels are a sustainable mannequin of energy, are fuels that deal not derived from oil colour and can include alcohols, biofuels, hydrogen, natural gas and propane 1. They are commonly solid, liquid or gas biofuels acquired from biomass, veggie oil, or generated from agricultural nutrition crops 6, 10. A viable alternative fuel must be economical, supply a net energy gain , be beneficial to the environment, and be able to be produced in considerable volumes with limited detrimental impacts6. The alternative fuels that are currently prevalent throughout the world are ethanol and biodiesel 7, 11, 12. ethyl alcohol as well referred to as ethyl alcohol, is a colourless liquid alcohol, less dense than water, with the chemical formula C2H5OH 13. Biodiesel is a carbon-neutral fuel that is a mixture of fatty acid methyl esters 13, 14.Alcohols grain alcoholEthanol is one of the most widely utilized liquid biofuels that can be combined with gasoline to create an ethanol blend fuel, or it can be used in pure form 7, 13. It may be derived by fermenting carbohydrates obtained from natural simoleonss, starches or cellulosic biomass in poses including sugar cane, corn or straw 7, 15. Generally, this process involves the yeast driven excitement of glucose in which the energy from the glucose is concentrated in the ethanol and CO2 is released as seen in equatio n 1 13.13The USA and Brazil are presently the two major producers of bioethanol with corn and sugar cane the radical base plants for the US and Brazil, respectively 16, 17. Current fuel yield for corn ethanol has been demonstrated at 1135 1900 L/hectare to achieve 50 percent of American transport fuel demands, more than 157 percent of USA cropland would impoverishment to be utilized 17. In 2005/2006, Australia produced and consumed 41 jillion litres of ethanol fuel 8. Use and production of ethanol, however has been demonstrated to be increasing 8. In Australia, since 2003, the maximum allowed limit of ethanol in ethanol-petrol blends has been 10 percent 8. In 2007, there were three ethanol production facilities operating in Australia that generated ethanol from grains, such as sorghum and wheat, and from sugar cane, with production capacities of over cl million litres annually 8.BiodieselsBiodiesel generation emerged in the late 1990s and has act to rapidly increase 13. Biodies els are produced from a variety of seed plant oils, such as soybean, palm or rapeseed oil, or from animal fats 10, 15, 18. They are mostly manufactured through the process of transesterification 18. Transesterification involves the mixing and of an oil with alcohol in the presence of a catalyst, such as sodium hydroxide, which reacts to create biodiesel and glycerine 18. The triglyceridies in the oil or fat are reborn into a glycerine molecule and three methyl esters of long kitchen be given fatty acid molecules (Figure 1)13.The glycerin by-product is not in merchandise demand due to the excess produced from biodiesel generation and recently been discovered to convert into propylene glycol, which has a large market, and acetol 13. Biodiesel manufactured from soybean produces more than 90 percent more energy than is needed to generate it 13.Figure Transesterification of a triglyceride 18.Biodiesel is manufactured globally, with the USA and Germany dominating the market 20. Arou nd the world, over 1.5 million tonnes of biodiesel is generated annually 15. In 2005/2006 Australia produced and consumed 16 million litres of biodiesel fuel 8. Use and production of biodiesels has change magnitude since8. In Australia biodiesel can be utilized as a replacement for diesel or in a biodiesel-diesel blend of between 5 and 20 percent biodiesel 8. Investigations into utilizing canola or mustard for biodiesel production are occurring in southern Australia while currently, a range of fats and oils are used, such as tallow 8. In Australia, biodiesel production capacity is greater than ethanol production capacity 8.Advantages and Disadvantages of Alternative FuelsAlternative fuels such as ethanol and biodiesel have numerous advantages and disadvantages regarding environmental and societal impacts. The replacement of fossil fuels with alternative fuels could leave behind in a decrease of CO2 emissions, a decrease in air pollution, reduce acid rain and decrease global warmin g3. supernumerary benefits include sustainability, fuel security, regional development and a decrease in rural poverty 7, 21. The land area required to generate competent alternative fuel to meet demands however, may compete directly with factory farm requirements, water use, may build pollution from the use of herbicides and pesticides, and could takings in the destruction of natural habitats and a decrease in biodiversity 3, 21, 22. In evolution countries, the expansion of the alternative fuel industry could increase deforestation, decreasing the removal of CO2 from the atmosphere through photosynthesis 12. The prices obtained for the sale of, for example, Australian produced alternative fuels is multivariate and depends on domestic prices for petrol and diesel, the world prices of oil and the Australian change rate 8.EthanolAdvantages there are several advantages concerning the use of ethanol as an alternative fuel. Carbon dioxide in the atmosphere is removed by the crop used for ethanol generation, turn uping in the process being carbon neutral 15. Using ethanol over fossil derived fuels can result in a reduction of CO2 up to 75 percent 24. Higher densities of ethanol fuel and air can be combusted in an engine compared to petroleum due to ethanols constricted boiling point range and high latent heat of vaporization (Table 1) 10, 16. Additionally, higher energy dumbness can be achieved in the engine due to a inflict stoichiometric air to fuel ratio 10, 16.This may produce heighten engine efficiency and elevated power outputs in ethanol fuelled vehicles when contrasted to petroleum fuelled vehicles. The use of ethanol as an alternative fuel can result in lower pollution emissions compared to fossil fuels, particularly regarding particulates, alkenes, aromatics and carbon monoxide 13.DisadvantagesThere are disadvantages associated with the use of ethanol as an alternative fuel. At present, ethanol is not economically competitive 15, 24. Expensiv e production costs associated with ethanol can be generated due to the use of water for irrigation, herbicides and pesticides, fertilisers, and machinery maintenance 11. former(a) expenses may be accrued from wages, insurance, land charges, and depreciation of farm assets 11. Ethanol has a lower amount of energy generated per litre combusted, is more acrid than gasoline and is toxic to ecosystems 13, 20. The use of pure ethanol is limited in colder climates by their low vapour pressures 13. Ethanol production from crops is stated to cause environmental degradation such as dust and exhaust emissions, displacement of alternative land uses, pollution of surface and ground water systems, increased turbidity in surface waters, salinity and bioaccumulation of some pesticides 9, 11. There are a number of environmental problems related to corn generated ethanol such as denitrification, erosion, and nitrogen leaching 9, 11. Ethanol crops are generally inefficient and the yields vary dramat ically between various crops 15, 17. The disadvantages noted above augur that currently, ethanol is not a viable alternative fuel.BiodieselAdvantagesA number of advantages are linked with the use of biodiesel fuel over fossil derived diesel fuel. Biodiesel production is stated to be sustainable, environmentally friendly, nontoxic, and biodegradable 1, 5, 10. Biodiesels properties are alike the properties of fossil derived diesel, Table 1, suggesting it can be used unmodified in indirect injection diesel engines 5, 16. Table 1 demonstrates that biodiesel has a higher flash point than petroleum-based diesel making it is safer to store and transport 10, 16. Biodiesel fire cleanly, and the emissions produced have fewer pollutants including less carbon monoxide, sulphates and sulphur oxides, hydrocarbons, nitrogen and particulates 1, 5. It to a fault has a small increase in fuel economy and transcendent lubricity compared to fossil derived diesel, which can reduce engine wear 7 14.Dis advantagesThere are many disadvantages regarding the use of biodiesel as an alternative fuel. Biodiesel production from crops competes with food supply, can detrimentally impact the environmental through nitrogen and the Tempter leaching, and loss of biodiversity 6, 7. Biodiesel generally generates lower power and torque than petroleum-based diesel and can have a higher fuel consumption 10. Biodiesels are also not currently economically competitive 6. They are stated to have higher emissions of nitrous oxides and cold start problems 7. The biodegradability of biodiesel can create problems regarding fuel stability and long-term storage 14. Methyl ester fatty acids deteriorate in conditions with high temperatures, sunlight, oxygen or non-ferrous metals 14. The disadvantages noted above indicate that currently, biodiesel may not be a viable alternative fuel.ConclusionAlternative fuels such as ethanol and biodiesel have both advantages and disadvantages regarding impacts on the environ ment. Ethanol is usually produced through the fermentation of carbohydrates while biodiesel is generally produced by transesterification. indoors Australia, the industry of alternative fuels is steadily expanding. Advantages of alternative fuels may include fall emissions and air pollution, reduced impact on global warming, sustainability, fuel security, regional development and a decrease in rural poverty. Disadvantages of alternative fuels may include land use competition, water use competition, pollution from the use of herbicides and pesticides, deforestation, the destruction of natural habitats, and a decrease in biodiversity. Currently, the production and use of the alternative fuels ethanol and biodiesel do not appear to be viable.