Tuesday, January 28, 2020
The Pros And Cons Of Biofuels Environmental Sciences Essay
The Pros And Cons Of Biofuels Environmental Sciences Essay Nowadays, as the problem of greenhouse gases emissions is getting more serious, Carbon-negative biofuels represent the first potentially huge assault on the problem, in ways that are already technically feasible and practicable (Mathews, 2008). Scientists are having their research on how to ease or solve these problems. The topic of biofuels is being more popular in the recent years because it has the most potential to be a significant source of energy. Biomass is providing a surprisingly large amount of the worlds energy 10% of total global primary energy consumption (Energy Future Coalition, 2007). Advantages of biofuels Safety Biofuels are safe to handle and transport because they are biodegradable, much less toxic than even table salt (ten times), and have high flashpoints of about 300oF compared to gasoline and petroleum diesel fuel (diesel has a flash point of 125 F, for comparison) (Biodiesel Chemical Safety Data Oxford University). Because of its safety, the number of incidence of severe vehicle fires can be reduced, and its safety making it to be one of the safest of all alternative fuels. Also, biofuels produce fewer by-products than conventional hydrocarbon based fuels after combustion or burning. The conventional hydrocarbon-based fuels will produced a greater output of some noxious by-product, for example, carbon monoxide. That means, biofuels could lead to less localized smog in urban centers (Charles et al). Energy security and saving money An opportunity of developing countries to enhance national energy security has been provided by biofuels, by reducing expenditures and dependence on fluctuated price of oil. For example, Brazil, she started the biofuels programme when the oil prices increase in 1970. The initial biofuels programme took about 4 billion US dollars, and nowadays 100 billion US dollars are saved because of the programme (Raswant et al., 2008). For the world, there is the potential for expanded ethanol production to replace 10% of the worlds gasoline with enthanol that is 25 to 30 billion gallons (Charles et al., 2007). 2.3 Agriculture development The introduction of biofuels can help bring modern energy services to rural areas particularly. 75% of the worlds poor can be employed due to the greater investment are fostered. On the other hand, biofuels industry can also create new job opportunities in rural areas and a major new source of income for farmers can also be provided. And farmers can enter a market with higher prices and rising demand by producing transportation fuel. Growing energy crops is more likely to attract the kind of foreign investment that can modernize their agricultural practices as well as increase their food production (Energy Future Coalition, 2007). Carbon-negative Biofuels is carbon negative fuel because it can remove carbon that in the atmosphere and the theory is: biofuels can draws carbon by photosynthesis (growing of biomass). The technical means of turning biofuels carbon negative are already available. The following is the explanation of the difference between carbon positive, carbon neutral and carbon negative fuels. Firstly, carbon positive fuel, it provides negative effect to climate because the fuels are drawn from fossil fuel deposits, and burned thus releasing carbon dioxide to the atmosphere. Secondary, carbon neutral fuels, theses fuels will absorb carbon dioxide when they grow, but the same amount of carbon will release back into the atmosphere when burnt. This is definitely a carbon-neutral cycle. Finally, carbon negative fuels, these fuels will also absorb carbon dioxide when they grow as well as carbon neutral fuels, but the difference is when carbon negative fuels burn and used as fuel, not the same amount of carbon dioxide which absorb when they grow will release, they tend to release small amount into the atmosphere. In other words, these fuels can reduce carbon dioxide (Mathew, 2008). Diagram source: http://biopact.com/2007/10/strange-world-of-carbon-negative.html. Convenience Biofuels is convenience because it does not require changes to switch to use compare with the other renewable energy, for example, solar energy and wind energy. (Want to know it, 2010). For the transport vehicle, Use of bio-diesel and bio-petrol do not require any change in the vehicle engine (Times internet limit, 2008). 3. Disadvantages Soil degradation The more alternative energy sources, for example biofuels, the greater the demand of agricultural land. Such as Amazon basin, scientist predicted deforestation will escalate, with growing amounts of virgin rainforest being cleared for farmland, thus greater soil degradation are going to ensue (Charles et al). Impact on water resources Increase the use of biofuels will definitely increase the use of water resources, such as: water will be used for the irrigation of crops used as feedstock for biodiesel production and water is used for boiling and cooling in the process of producing biofuels in refineries. (Energetics Incorporated Columbia, 2007). And the use of water resources is keep increasing, for example, in the United States, the number of ethanol factories has already increased from 50 in 2000 to about 140 in 2008 and 60 is constructing, this trend represent the consumption of water is getting serious (Julian Rubin, 2008). Soil erosion, deforestation and loss of biodiversity On a small scale, as the carbon compounds in waste biomass are consumed by other microorganism, they break down the biomass in the soil to produce valuable nutrients that are necessary for crops. Lets move on to a larger scale, plant biomass waste provides small wildlife habitat. And when human use the biomass to produce biofuels, the organisms and natural habitats are to be threatened. For Soil erosion, when cellulosic ethanol is produced from feedstock like switchgrass and saw grass, the nutrients that required to grow the lignocellulose are removed and cannot be processed by microorganisms to replenish the soil nutrients, then the soil is of poorer quality. For the deforestation, lets have an example, Amazon rainforest, in order to produce sugar cane for ethanol fuel in Brazil, an areas have been cleared by burning and slashing techniques, large scale of deforestation was conducted, the major plant is mature trees, which can help remove carbon dioxide through photosynthesis, and this function is more efficient than sugar can or most other biofuels do. This deforestation is therefore contributes to un-sustainable global warming atmospheric greenhouse gas levels, loss of habitat, and a reduction of valuable biodiversity (Julian Rubin, 2008). Problems caused to car engine Nowadays, Biodiesel is using in order to replace petrol diesel in car engine, and biodiesel is made from vegetable oils, some problems occur when using biodiesel, such as, coking and trumpet formation on the injectors, oil ring sticking, and thickening and gelling of the lubricating oil, it is because of the higher viscosity and density, lower heating value and lower cetane number of vegetable oils. The following table show the above disadvantages of vegetable oils as diesel fuel compare with D2 fuel (Kralova and Sjoblom, 2010). Table Source: Kralova and Sjoblom, 2010 4. Conclusion To conclusion, biofuels have advantages and disadvantages, for the advantages, biofuels is safe because it has high flesh point, enhance national energy security and help countries saving money from import oil. Also, it can bring modern technology to rural area, and create job opportunity. And the most important advantages are, using biofuels can definitely ease the problem of carbon emission. On the other hand, biofuels have disadvantages as well, deforestation rate will increase, thus affect the biodiversity. And more water resources will be used. Lastly, using of biofuels in car engine will bring harms to the engine. Recommendation From the advantages and disadvantages which has discussed above, yes, it does help ease the problems of global warming from reducing carbon or provides benefit, but biofuel still have lot of hurdles to tackle. Therefore, it is too early to say that biofuels are the significant energy in the future. In my opinion, the research on biofuels should keep going and it would be great if more generations of biofuel appear, then the uses of biofuel can be apply and spread more widely. On the other hand, deforestation should not be employed, because it will totally affect the biodiversity, not only the biodiversity, but also soil.
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