香港代写assignment|Biomass Energy

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Biomass Energy

The use of biomass energy as a wide spread, renewable power source provided with proper knowledge, state control and technological how-to, can change both the earth's environment and our attitude towards alternative power resources. To understand how this can happen, the basics of what biomass energy is and how it works have to be presented. All organic matter, such as agricultural residue, wood and animal waste, energy crops, and methane, is a potential source for biomass energy ( Biomass energy can be produced by either growing crops especially for this purpose (i.e. sugarcane, soya bean, corn, sweet potato, maize, willow and eucalyptus trees), or converting organic waste ( The organic matter can be burned to produce heat, like the wood fire of old, or they can produce ethanol or other alcoholic fuels ( There are differing opinions between respectable scientific communities and one has to analyze the different arguments for and against the use of biomass energy in order to make an informed decision concerning biomass energy.

There are a number of arguments advocating the use of biomass energy. As we see an increase of the greenhouse effect, the trend is to start using renewable power sources. Because in order for biomass energy to be produced needs only organic matter and no chemical is needed for its production, it qualifies as a clean renewable power source. For these reasons, biomass energy generates far less air emissions than fossil fuels. Methane, a more powerful greenhouse gas, can be used for the production of biomass energy thereby decreasing the methane levels in the atmosphere. Biomass materials are often waste products from existing industrial activities that would otherwise be disposed of--at considerable cost. For example, if you burn unusable waste material such as bark, construction waste and tree clippings, you reduce the pressure to expand local landfill sites while generating useful energy (

Biomass energy decreases the reliance on fossil fuels that may be imported, and whose price therefore is subject to variable economic and/or political issues. Bioenergy has a generally positive impact on the local economy. Biofuels are bulky and have a low-energy density so it is not economical to transport them long distances. As a result, the money spent to purchase biofuels generally remains in the local area ( As biomass energy is produced locally, it creates thousands of jobs at a local scale as it is labor intensive to create biomass energy. As such, the production of biomass energy helps revitalize rural communities. Extra income without an investment in special equipment can be derived from the collection of agricultural residues, such as straw or corn stover, or from the removal of dead, diseased or low-quality trees from forests.

However, there are arguments that contradict those above. Scientists found that reforestation would sequester between two and nine times as much carbon over 30 years than would be saved by burning biofuels instead of gasoline. 'You get far more carbon sequestered by planting forests than you avoid emissions by producing biofuels on the same land' says a prominents scientist ( The unsustainable and uncontrolled conversion of natural and even virgin ecosystems into managed energy plantations in order to produce material suitable for biomass energy, can lead to the release of carbon from the soil as a result of the accelerated decay of organic matter. ( It has been established that since the beginning of farming the soybean in Brazil, seven million hectares of the Amazonian rainforest have been converted into energy plantations. Thus, the concerns that environmentalists have expressed about the destruction of the forests in order to make room for biomass crops, such as maize and sugarcane, have been realized. Says, Renton Righelato of the World Land Trust, a conservation agency that seeks to preserve rainforests, "When you do this, you immediately release between 100 and 200 tonnes of carbon [per hectare]" ( Another by-product of the planting of crops suitable for the production of biomass energy is the loss of biodiversity. Transforming natural ecosystems into energy plantations with a very small number of crops, as few as one, can drastically reduce the biodiversity of a region. Such 'monocultures' lack the balance achieved by a diverse ecosystem, and are susceptible to widespread damage by pests or disease (

Another important argument is that there simply may not be enough land to grow energy crops and food crops simultaneously. According to a UK survey, the most productive energy crop in the UK is rapeseed and the average yield is 3-3.5 tons per hectare and one ton of rapeseed produces 415 kg of biodiesel, so every hectare of arable land could provide 1.45 tons of transport fuel. Road transport in the UK consumes 37.6m tons of petroleum products a year ( The total hectares needed to be planted in order to produce the biodiesel quantity of equal to 37.6m tons of fossil fuel would be roughly 25.9m hectares. The UK does not have this much arable land. In the case of Brazil, Alexandre Conceicao, a member of the MST (Landless Workers Movement), pointed out the orientation was towards the global market concerning energy crop plantations with no regard to the domestic production of food ( So, there might not be any reliance on foreign fossil fuels, but there may be reliance on foreign food exporters.

There are also arguments against the intended location of future energy crop plantations. There has been the suggestion that by converting arable land in Africa into energy crop plantations, both global warming would be tackled and Africans would be helped. It was said that this strategy, "provides a sustainable development path for the many African countries that can produce biofuels cheaply" ( Although palm oil can produce four times as much biodiesel per hectare as rapeseed and is grown in places where labor is cheap, planting it is already one of the world's major causes of tropical forest destruction ( It is obvious that the production of biomass energy in this manner would entail serious environmental consequences.

The possible creation of jobs has also come under doubt. There have been protests in Brazil about the 'slavery' conditions that the sugar cane plantation workers face. "The social cost of this policy is the overexploitation of labour with an army of seasonal workers who cut one ton of sugar cane for 2.50 reals (1.28 dollars) in precarious conditions which have already caused the deaths of hundreds of workers," says Alexandre Conceicao of the MST ( Camilla Moreno of the Rural University of Rio de Janeiro said that,

the growth of the ethanol industry is breathing life into 'a modern-day version of the sugar plantation slave-labour past,' along with the expansion of a new form of 'ecological imperialism.' Moreno pointed out that large tracts of land have been purchased by international (largely U.S. and European) investment funds, which has brought 'a new form of capitalism that was not familiar to Brazil' (

The above statements show that not only do the Brazilian people, as a whole, do not benefit from the production of biomass energy, but also that the actual workers are not rewarded properly for their work and work under wretched conditions.


广泛的传播,可再生能源发电源提供正确的知识,国家控制和技术如何利用生物质能源,既可以改变地球的环境和我们的态度替代能源资源。要明白怎么会发生这种情况,什么生物质能的基本知识,以及它是如何工作将提交。所有的有机物,如农业残余物,木材和动物废物,能源作物,和甲烷,是一个潜在的通生物质能( ~ ene02p10/biomass.htm )的。生物质能可所产生的无论是种植作物,特别是为这个目的(如甘蔗,大豆,玉米,红薯,玉米,柳树和桉树) ,或将有机废物( dieret /生物/ biomass.html ) 。有机物可燃烧以产生热量,像老木生火,或者他们可以生产乙醇或其他的酒精燃料“ ( ~ ene02p10/biomass.htm )的。可敬的科学界之间有不同的意见,并有不同的参数进行分析和对生物质能的利用,以便作出明智的决定,关于生物质能。
提倡使用生物能源有许多的参数。正如我们所看到的温室效应增加,趋势是开始使用可再生能源发电来源。因为为了要生产生物质能只需要有机物质,其生产所需的任何化学物质,它有资格作为一种清洁的可再生电源。由于这些原因,生物质能产生比化石燃料排放量远远低于空气。更强大的温室气体中,甲烷,可用于生产生物质的能量,从而减小了在大气中的甲烷含量。生物质材料往往是浪费从现有的工业活动,否则将被出售的产品 - 在相当大的成本。例如,如果你烧不可用废料如树皮,建筑垃圾和树剪报,可以减少压力,要求扩大当地的垃圾填埋场,同时产生有用的能源( CAID = 2& PGID = 62 )。
生物质能减少对化石燃料的依赖可能进口的,其价格因此受经济变量和/或政治问题。生物能源具有普遍对当地的经济产生积极的影响。生物燃料是笨重的,具有低能量密度,所以它是不经济的长距离运输。因此,所花的钱购买生物燃料一般保持在当地( ) 。由于生物质能源在当地生产,创造数以千计的就业机会,在当地的规模,因为它是劳动密集型的创建生物质能。因此,生物能源的生产有助于振兴农村社区。从农业残余物,如稻草或玉米秸秆,或去除死亡,患病或低质量的树木从森林收集,没有专用设备的投资可以得到额外的收入。
不过,也有与上述矛盾的论点。科学家发现两九次之间尽可能多的碳通过燃烧生物燃料代替汽油将被保存超过30年,造林隔离。 “你得到更多的种植森林固碳比你避免在同一块土地生产生物燃料的排放量,说:”一个的prominents科学家不可持续的,不受控制的自然的,甚至处女生态系统转换成能量管理种植园,以生产适合生物质能源材料,加速有机物质衰变的结果可能会导致从土壤中的碳释放。 ( ) 。它已经建立,自年初以来,农业在巴西的大豆, 700万公顷的亚马逊雨林已转换成能量的种植园。因此,关注环保的森林的破坏表示关注,以便使生物质作物,如玉米和甘蔗的空间,已经实现。说,保护世界土地信托机构,旨在保护雨林, Renton Righelato的, “当你这样做,你立即释放100吨和200吨的碳每公顷[ ]”适合用于生产生物能源作物种植的另一个副产品是生物多样性的丧失。自然生态系统转变成一个非常小的一些作物的种植能源,作为一个很少,可以大大减少一个地区的生物多样性。这种“单一种植”缺乏一个多样化的生态系统达到平衡,容易受到广泛的破坏害虫或疾病( )的。
另一重要原因是,有可能根本没有足够的土地来种植能源作物和粮食作物的同时。据一家英国的调查,在英国是最有生产力的能源作物油菜籽平均单产为每公顷3-3.5吨一吨菜籽油生产生物柴油415公斤,每公顷耕地可提供1.45吨的运输类燃料。公路运输在英国消耗37.6米万吨,石油产品一年( ) 。需要种植以生产生物柴油的数量等于化石燃料37.6米吨的总公顷。将大致25.9米公顷。英国没有这么多的耕地。在巴西的情况下,亚历山大·孔塞桑, MST (失地工人运动)的成员,指明了方向是走向全球市场的关于能源作物种植园,没有考虑到国内生产的食品( / news.asp中? idnews = 38051 ) 。因此,有可能是任何对外国化石燃料的依赖,但也有可能对外国食品出口的依赖。
也有对未来的能源作物种植的预定位置的参数。已经有,非洲耕地转换成能源作物种植,既全球变暖将解决和非洲人将帮助的建议。有人说,这一战略“提供了可持续发展的道路,为许多非洲国家可以生产生物燃料便宜” ( ) 。尽管棕榈油可以生产四倍多的生物柴油每公顷油菜籽生长在劳动力便宜的地方,种植它已经是世界热带雨林破坏的主要原因之一( /功能/生态/ fuelines.html的)。很明显,以这种方式生产生物质能源将产生严重的环境后果。
可能创造就业机会也受到怀疑。目前已经在巴西大约抗议'奴役'的甘蔗种植园的工人面临的条件。 “这一政策的社会成本是2.50雷亚尔(1.28美元) ,在不稳定的条件下,已经造成数百名工人死亡谁砍一吨甘蔗的季节工人与军队的过度劳动, ”亚历山大说,孔塞桑的MST ( ) 。农村里约热内卢大学的卡米拉·莫雷诺说,
乙醇行业的增长注入生命'一个现代版的甘蔗种植园的奴隶劳动的过去,随着一种新形式的“生态帝国主义的扩张。 ”莫雷诺指出,已经购买了大片土地(主要是美国和欧洲)国际投资基金,这带来了一种新形式的资本主义' ,这是不熟悉巴西( ? = 38051 idnews )