Wednesday, August 21, 2019
Biofuels And Bioenergy
Biofuels And Bioenergy Introduction The use of fossil fuel as a source of energy has aided the development of the human race for many years. This technology has allowed for many benefits such as electricity, transportation, manufacturing machinery etc. The world is faced with the complex economic and environmental issues associated with energy use that must be addressed if we are to maintain and improve our lifestyle. Our economy depends on low cost energy. The idea of renewable energy has been around for quite some time but did not receive much attention mainly due to lower oil prices over half a century ago. However the time has now come when it can no longer be ignored as we enter a new level of consciousness about our fuel consumption and the lack of fossil fuels we have including awareness about the impact on the environment[i]. The pressure to have cheaper alternative energy has become more important especially at a time where we are facing a global recession. As pressing as these economic issues become, we are also faced with even greater environmental consequences if we do not change our energy use patterns. Looming in the background of everything is the mounting concern of carbon dioxide (CO2) build up and other so called greenhouse gases in the atmosphere, which trap the heat that usually radiates from the earth, and cause global climate change[ii]. Therefore clearly, developing alternatives to fuel should be one of the highest priorities of many nations. With record oil prices, the future of Biofuels made from biomass is of keen interest to the world. The global production of Biofuels has increased from 4.8 billion gallons in the year 2000 to about 16.0 billion in the year 2007, but this still accounts for less than 3 percent of the global transportation fuel supply[iii]. This literature reviews the technology of biofuels, their production, usage and impact on a global scale. What are Biofuels? A biofuel can be defined as fuel derived from biomass which is found in many living biological material. Living organisms and their metabolic byproducts such as manure have been successfully used as biomasses. Biomethane, Bioethanol, Biodiesel Biobutanol These fuels can be burnt to produce heat and power, used to run vehicles (Brazil has the highest proportion of road vehicles designed to run on biofuels which peaked at 90% in the 1980s) or powering fuel cells. The content by volume of a biofuel is a minimum of 80% biomass products. Biomass is a form of stored energy just like coal of petrol. The main advantage of biofuels compared with most other traditional fuel types is that this is a biodegradable technology, therefore it is comparatively harmless to the environment. A large amount of biofuels come from specifically grown agricultural crops such as sugar cane and corn. Another useful source is biodegradable by-products that come from industries, households and forestry e.g. timber and rice which can also be used to generate biofuel. There is a growing interest in the field renewable energy technology. And this has resulted in research currently being carried out on projects such as the large scale utilization of micro algae as an energy source. Brief History of Biofuels The initial use of biofuels was in the early days of the automobile industry. A German inventor known as Nikolaus August Otto came through with his invention of running the combustion engine using ethanol. Another historic invention was the powering of diesel engines using peanut oil was by Rudolf Diesel, the German inventor. But unfortunately however in the 19th century when crude oil became cheaper, cars began using fuels from oil which has led to where we are now. There is an increasingly importance in the use of biofuels as a replacement, now being considered by many countries such as the United Stated, by 2025 aim to replace 75% of the oil coming from the Middle East. Over the last century, the world has become accustomed to petroleum based transportation fuels, lubricants and other useful products derived from fossil fuels. However the recent oil prices have been escalating ever since the 1970s fuel crisis and the global climate has changing drastically. Perhaps the time has come to learn a lesson from history and adopt the idea of biofuels for the benefit of the living to save the planet instead of taking the easiest and cheapest way out, saving the planet for the next generations to come. Case Studies and practices of Biofuels We will now look at a few case studies where Biofuels have been successfully used and utilized. Case Study 1 A Lesson from Brazil The worlds second largest ethanol program is based in Brazil and they are capitalizing on bountiful soybean supplies to spread out into biodiesel. About 20 percent of the countrys fuel supply is obtained from the nations sugarcane crop which is processed into ethanol. Brazils policy program was changed to encourage the nations energy independence and creating a substitute value added market for sugar producers. The following was set off in the 1970s right after the famous OPEC oil embargo. Sugarcane producer have been well supported by the government which has spent billions to develop distilleries, build infrastructure and promote the production of pure ethanol and other transport fuels[iv]. It was shown that while the costs were high, this program benefited by saving far more in foreign exchange from the resulting reduced petroleum imports. Brazil in the mid to late 1990s pursed a less intrusive move towards the elimination of direct subsidies and price settings for ethanol with two main elements. Which were a blending requirement (which is now about 25%) and tax incentives favouring the use of ethanol and its purchase for flex-fuel vehicles. Today 80 percent automobiles produced in Brazil have flexible fuel capability[vi], up from 30 percent in 2004. Ethanol is widely available to consumers at nearly all of Brazils 32,000 gas stations; the consumers primarily have the choice between a 100-percent hydrous ethanol and a 25-percent ethanol-gasoline blend on the basis of relative prices[vii]. Roughly 20 percent of current fuel use in Brazil is ethanol, but it will be challenging to raise the share as Brazils fuel demands keep growing with the rest of the worldou. Brazil is a middle-income economy having a per capita energy consumption which is only 15 percent that of the United States and Canada. Unfortunately, the current biofuel production levels in Brazil are not much superior than they were in the late 1990s due to the limitations by the economy and environmentalist. Biofuels have however, come under serious attack recently saying that it is eating into farmlands meant for food production. And as a result last year the European Union backed out from a commitment which would introduce a 10 percent compulsory quota of biofuels in all transportation by 2020[viii]. While admitting that ââ¬Å"biofuels are no silver bullet,â⬠the authorities in Brazil understand and insist that biofuels are the best way forward for developing countries[ix]. A large expansion in ethanol production is underway in the United States, spurred by high oil prices and energy policies The production of ethanol is the U.S climbed to almost 5 billion gallons[x] in 2006, up nearly 1 billion gallons from 2005. Regardless of the speed and degree of this increase, the industry has stepped up the speed of expansion, with production expected go as high as 10 billion gallons by 2009[xi]. Market conditions and policy factors are fueling the rising interest in ethanol. A rapid run-up of oil prices over the past several years has combined with provisions of the Energy Policy Act of 2005 and already existing Federal and State biofuel programs to provide economic incentives for an expansion of U.S. ethanol production. This increase in prices reflects rising global demand for crude oil resulting from strong world economic growth, including rapid manufacturing gains in China and India. Further growth in global economic activity will continue to drive up world demand for oil, particularly in highly energy-dependent economies in Asia. Although the increase in demand is likely to be partly offset by future oil discoveries, more new technologies for discovery and extracting oil, and constant expansion and enhancement in renewable energy, the oil prices are expected to remain high by historical standards. As a result of these strong incentives, the ethanol production capacity has increased over the last year as more production plants have been built or are under construction. Once the constructions of the new plants are complete according to the Renewable Fuel Program of the Energy Policy Act of 2005 renewable fuel use should reach 7.5 billion gallons by year 2012[xii]. The vast expansion in biofuels production and use mandated by EISA will require the development of new methods and equipment to collect, store, and pre-process biomass in a manner acceptable to biorefineries. These activities, which constitute as much as 20% of the current cost of finished cellulosic ethanol, are comprised of four main elements: Harvesters collectors that remove feedstocks from cropland and out of forests. Storage facilities that support a steady supply of biomass to the biorefi nery, in a manner that prevents material spoilage. Preprocessing/grinding equipment that transform feedstocks to the proper moisture content, bulk density, viscosity, and quality. Transportation of feedstocks from the field to the biorefinery. Case Study 3 Biofuels in Senegal JATROPHA PROGRAM It all started in India when Jatropha Carcus-ââ¬Å"Hondurasâ⬠were carried in by Portuguese sailors a few hundred years ago. They were planted around other valuable plantations as a fence because animals and insects were repelled away from it. Meanwhile, Indian farmers found out that the nut contained oil which they used in their oil lamps. Over the years, these farmers bred the plant to have higher oil content as high as 40-50%. India has always been interested to produce biofuels however it had to come from non-food crops. The Biodiesel produced required certain characteristics for example it had to come from non-food crops and grown in non-prime agricultural land. Jatropha fulfilled these requirements as it is resistant to droughts, requiring minimum use of pesticides and fertilizers. Jatropha plants are very hardy and grow very fast producing seeds for extraction within a few months. The main objective of the program is to ensure Senegals self-sufficiency in biodiesel by 2012 with the production of 1 190 000 000 litres of crude Jatropha oil. This production will represent 1 134 000 000 litres of refined oil which can be used as biodiesel for vehicles as well as to generate power[xiii]. It is also the aim of the program to accelerate the modernisation of the agricultural sector, to create 100,000 direct employment opportunities for the local population particularly in the rural areas where the cultivation of jatropha will be mostly undertaken. The successful implementation of the jatropha program will ensure the diversification of the cultivation of cash crops, reduce the energy bill of households in the country as well as its heavy dependence on imported energy and improve the countrys international trade and balance of payment. Moreover, the program will contribute towards the reduction of environmental pollution caused by vehicle engines; and will also help alleviate poverty and inequality between rural and urban areas. BIOFUEL PRODUCTION TYPES SOURCES Biofuels can be classified in two ways, firstly by the state at which the fuel exists in their natural form which are mainly gas, liquid or solid. And secondly by the sources they have been produced from and the technology used to produce them. In this literature review, biofuels have been classified according the second way. FIRST GENERATION (food crops) First generation biofuels are derived from food crops such as starch, sugar and vegetable oil using conventional techniques discussed later on. Several types of first generation biofuels are discussed briefly below. Biodiesel Biodiesel is probably the most common and most popular type of biofuel in the world because it also is the easiest to produce from ordinary vegetable oil. Biodiesel is produced very simply by combining any type of oil or biomass with methanol and sodium hydroxide[xiv]. It can be used on any diesel engine without any changes to it by mixing with mineral diesel as was described earlier in the ââ¬Å"History of Biofuelsâ⬠section. Vegetable oil These kinds of oil can be either used for cooking purpose or even as fuel. The main fact that determines the usage of this oil is the quality. The oil with good quality is generally used for cooking purpose. Vegetable oil can even be used in most of the old diesel engines, but only in warm atmosphere. In most of the countries, vegetable oil is mainly used for the production of biodiesel. There has a been great interest shown by European countries and the USA, the graphs below show a rising trend of biodiesel production is USA and many countries of Europe. Biogas Syngas Biogas is produced from organic materials by anaerobic digestion. Waste materials which are biodegradable can also produce biogas if they are fed into anaerobic digesters[xv]. The resulting biomass can be used as fertiliser for agricultural usage. Biogas is rich in methane gas which can be recovered and used as burning fuel. Methane gas is also produced by the natural decay of garbage dumps over time. Another process to produce Syngas or biosyngas is by gasification of biomass into carbon monoxide and hydrogen. Hydrogen can be recovered from syngas or the syngas can be converted to diesel fuel using Fischer-Tropsch process[xvi]. Bioalcohols (bioethanol) Enzymes and micro-organisms are used to produce alcohols through the process of fermentation of starches and sugar[xvii]. Ethanol being the most common of those bioalcohol as in bioethanol produced from sugar cane in Brazil. A significant amount of ethanol is also produced from sugar beets and corn by fermentation in other parts of the world. SECOND GENERATION (non food crops) Second generation of biofuels had been developed to use biomass left from the non-food parts of current crops such as stems, leaves and husks left behind after the important parts of the crop has been taken. It also includes biomass from non food crops such as Jatropha plant (which are toxic), switch grass and industrial waste such as wood chips, skin and pulp from fruit pressings. This generation of biofuels is not cost competitive with existing fossil fuels, do not threaten food supplies and biodiversity[xviii]. THIRD GENERATION (agriculture) Third generation biofuels is obtained from algae and this is also called advanced biofuel. Algae is easy to grow and it is a high-yielding feedstock for the production of biofuel as it produces 30 times more energy per acre of land than traditional crops such as corn or soybean[xix]. They are biodegradable so it is environmentally friendly. Similar to obtaining the oil from vegetation, algae contains almost 40-50% oil which is squeezed out and the remaining biomass can be used as fertilizer or high protein animal feed. The oil from algae can be converted to biodiesel. FOURTH GENERATION (biodiesel to gasoline) Last but not least is fourth generation biofuels which is still undergoing research at the highest levels. The main aim is to convert biodiesel into gasoline similar to the one obtained from petroleum but it will be much cleaner with less harmful emissions. This is similar to how natural gas or methane is converted to petrol. However there is much more study required in this part and will probably not be available in 10-20 years time. First generation feedstocks include corn for ethanol and soybeans for biodiesel. These feedstocks are currently in use and their yields have been increasing. Second generation feedstocks consist of the residues or ââ¬Å"left-oversâ⬠from crop and forest harvests. They show much promise for near-term adoption with the development of cellulosic conversion technologies. Third generation feedstocks are crops whichrequire further RD to commercialize, such as perennial grasses, fast growing trees, and algae. They are designed exclusively for fuels production and are commonly referred to as ââ¬Å"energy cropsâ⬠. They represent a key long-term component to a sustainable biofuels industry[xx]. BIBLIOGRAPHY Charles E. Wyman (1996) Handbook on Bioethanol Production and Utilization, Taylor Francis Publishers, pg 1 Intergovernmental Panel on Climate Change. 1990. J.T. Houghton, G.J.Jenkins, and J.J. Ephraums, eds. ââ¬Å"Climate Change-the IPCC Scientific Assessment,â⬠Cambridge, United Kingdom: Cambridge University Press. Amber Waves, November 2007, Volume 5, Issue 5, William Coyle ââ¬Å"The Future of Biofuels A Global Perspective. Amber Waves, November 2007, Volume 5, Issue 5, William Coyle ââ¬Å"The Future of Biofuels A Global Perspective. Market Research Analyst, ââ¬Å"Worlds Ethanol Production Forecast 2008 2012â⬠http://www.marketresearchanalyst.com/2008/01/26/world-ethanol-production-forecast-2008-2012/ Flex-fuel Vehicles inBrazil: http://alternativefuels.about.com/od/ethanol/a/ffvsbrazil.htm Amber Waves, November 2007, Volume 5, Issue 5, William Coyle ââ¬Å"The Future of Biofuels A Global Perspective. CLIMATE CHANGE: ââ¬Å"Brazil Defends Biofuelsâ⬠, Claudia Ciobanu, http://ipsnews.net/news.asp?idnews=49597 CLIMATE CHANGE: ââ¬Å"Brazil Defends Biofuelsâ⬠, Claudia Ciobanu, http://ipsnews.net/news.asp?idnews=49597 Green Car Congress, ââ¬Å"Energy, Technologies, Issues and Policies for Sustainable mobilityâ⬠: http://www.greencarcongress.com/2007/08/us-ethanol-prod.html Amber Waves, September 2007, Volume 5, Issue 5, Paul. C. Westcot ââ¬Å"U.S. Ethanol Expansion Driving Changes Throughout the agriculture sector.â⬠Shurson, Jerry, Mindy Spiehs, Jennifer Wilson, and Mark Whitney. ââ¬Å"Value and use of ââ¬Ënew generation distillers dried grains with solubles in swine diets,â⬠Alltechs 19th International Feed Industry Symposium Proceedings, May 2003. Ministry of Agriculture, New orientation for the Agriculture Sector Policy, REVA Plan, Special Biofuels Program, March 2007, ââ¬Å"Biofuels in Senegal Jatropha Program 2007-2009.â⬠Biofuel Organisation: http://biofuel.org.uk/first-generation-biofuels.html Biofuel Organisation: http://biofuel.org.uk/first-generation-biofuels.html Lee S., Lee L., Encyclopedia of Chemical Processing, CRC Press (2005), ââ¬Å"Biofuels and Bioenergyâ⬠pp123 Biofuel Organisation: http://biofuel.org.uk/first-generation-biofuels.html RenewableEnergy.com News Article: Next generation of biofuels; http://www.renewableenergyworld.com/rea/news/story?id=49099 Washington Post News Article; http://www.washingtonpost.com/wp-dyn/content/article/2008/01/03/AR2008010303907.html United States Department of Agriculture, ââ¬Å"National Biofuels Action Planâ⬠, September 2008, Board Action Area 2: Feedstock production pg 5.
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