Difference between revisions of "Biofuels"

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Biofuels have been championed as environmentally-friendly sources of power that help to tackle climate change. However, the report by the Organization for Economic Cooperation and Development (OECD) said biofuels may "offer a cure that is worse than the disease they seek to heal". <ref>Biofuels Offer Cure Worse Than the Disease - OECD,by Sybille de La Hamaide ,Planet Ark's daily Reuters World Environment News© 2008  [http://www.google.com link: http://www.planetark.com/dailynewsstory.cfm/newsid/44269/story.htm]</ref>
 
 
 
 
==Introduction==   
 
==Introduction==   
Concentrations of greenhouse gases (GHGs) in the Earth’s atmosphere have become a global concern because of their potential to '''affect''' long-term climate changes. About 82% of'''the United States'''' GHG emissions are from'''the combustion of''' fossil fuels used to generate electricity and operate vehicles.  '''O'''ther emissions are from methane, (Applied Energy, Volume 71, Issue 1, January 2002,Pages 15-30).  On another hand, US agriculture's contribution to air pollutant as a consumer of energy is small, as agricultural crop, livestock and poultry production accounts for only about 1% of direct energy use. However, the production agriculture accounts for about 7% of annul net GHG emissions (US Department of Agriculture, 2004a). Increase in agricultural productivity and conservation can reduce energy intensity of agricultural production and pollution. '''These last two sentences were very confusing.  Are they really necessary? It seems like the main point you want to make starts in the following sentence.'''Recent studies show that replacing fossil energy with renewable energy, like biofuels, is an important way of reaching the climate policy goals. (Soil and Tillage Research, Volume 61, Issues 1-2, August 2001, Pages77-92). '''Maybe start right here! -->'''There is a significant opportunity to reduce pollutants and GHG emission'''s''' by using biofuels. Like biodiesel, biofuels have many desirable environmental properties. They are non-toxic '''and''' biodegradable, and biodiesel exhaust emits less toxic air emissions, carbon monoxide and particular matter than petroleum diesel (Graboski and McCormick, 1998). Biofuels also have advantages that the plants grown each year to produce the fuel sequester carbon, which offsets the carbon released during fuel combustion (National Renewable Energy Laboratory, 1998). '''Reread and reword this last sentence.'''
+
Biofuels are considered an energy source with high potential to address problems in several areas, such as the crisis of climate change, environmental degradation, energy supply and security<Ref>Runar Brännlund, Bengt Kriström, Tommy Lundgren and Per-Olov Marklund, ''The Economics of Biofuels'',2007</Ref>. The use of biofuels largely depends on the availablity of different feedstocks. However, biofuels have some common features that they are all non-toxic and biodegradable, and they can reduce greenhouse gas(GHG) emissions. Recent studies from ''Soil and Tillage Research'' show that replacing fossil energy with renewable energy like biofuels is an important way of reaching climate policy goals <Ref>R. Horn, M. Kutílek, R. Lal, J. Tisdall,''Soil and Tillage Research'' , Volume 61, Issues 1-2, Pages77-92, August 2001, </Ref>.
  
 
==Types of biofuels==
 
==Types of biofuels==
 +
The figure below shows that there are various opportunities for the production of biofuels. The features between biofuels and fossil fuels are quite similar. For instance, biodiesel is similar to fossil diesel, and bioethanol is similar to petrol. This is a great advantage since the existing infrastructure does not necessarily to be intensively change.
  
Today, there are various sources for the production of biofuels. Although all the transport fuels can be classified in fossil fuels, the process chains for all transport fuels are different since which types of primary sources are needed(see the table below).
 
 
'''Process chains for fuel production'''
 
  
 
[[Image:Process_chains_for_fuel_production.jpg]]
 
[[Image:Process_chains_for_fuel_production.jpg]]
Line 16: Line 11:
 
----
 
----
  
'''First generation biofuels'''
+
'''First-generation biofuels'''
 +
 
 +
PPO, biodiesel, ETBE and bioehthanol are the first-generation biofuels. They are generally produced by the action of microorganisms and enzymes through the fermentation of any biological feedstock<Ref>Dominik Rutz & Rainer Janssen , ''Biofuel Technology Handbook'',page39, 2008</Ref>. Bioethanol, the most common biofuel feedstock, offers the greatest short-term bioful potential today since the conversion is widely developed and approved in practice <Ref>Sergey Zinoviev, Sivasamy Arumugam, and Stanislav Miertus,''Biofuel Production Technologies'', Institute of Energy and Environment, Leipzig, Germany and Paolo Fornasiero, University of Trieste, Italy, November 2007</Ref>. Although the first-generation biofuels are different in properties, technical requirements, economical aspects and potential usages, they can all contribute to guarantee long-term sustainability.
  
Bioethanol, the most commonly biofuel feedstock, is a fuel generally produced by the action of microorganisms and enzymes through the fermentation of any biological feedstock, which contains appreciable amounts of sugar or materials that can be converted into sugar such as starch or cellulose.
 
  
 +
'''Second-generation biofuels'''
 +
 +
Second-generation biofuels are derived from feedstocks, which are not traditionally used for human consumption. They include BTL fuels and ethanol from lingo-cellulose. These products are not yet commercial available since their conversion technologies are not improved enough as products of first-generation biofuels. However, second-generation biofuels are considered to be more environmental healthy and produce less GHGs than first generation biofuels. The reason is that they can make use of the vast majority of feedstock in the process of production and avoid the waste inherent in the production of first generation biofuels<Ref>Deurwaarder, E.P., 2005. Overview and Analysis of National Reports of the EU Biofuel Directive: Prospects and Barriers for 2005. ECN (Energy Research Centre of the Netherlands) http://www.ecn.nl/docs/library/report/2005/c05042.pdf</Ref>. Second-generation biofuels can not only help solve this waste problem, but also can supply a larger proportion of our fuel supply sustainably, affordably, and with greater environmental benefits.
  
'''Second generation biofuels'''
 
  
 
----
 
----
'''Pathways of Different biofuels'''
+
The figure below focuses on the pathways of biofuel production. It shows that feedstocks sources can be divided into animal fats, oil crops, sugar plants, starchy plants, cellulosic biomass and wet biomass. During the different processes, such as refining, extraction, hydrolysis and fermentation etc., they can be transformed into liquid or gaseous biofuels.
 +
 
 +
'''Pathways of Different biofuels'''<Ref>Dominik Rutz & Rainer Janssen , ''Biofuel Technology Handbook'',page39, 2008</Ref>
  
 
[[Image:Pathways_of_different_biofuels.jpg]]
 
[[Image:Pathways_of_different_biofuels.jpg]]
  
 
==Current biofuel promotion policies==
 
==Current biofuel promotion policies==
 +
A turning point for biofuels policies occurred in 2005–06, when several countries dramatically stepped up targets and mandates for biofuels to make a great promotion of their use<Ref>Koizumi, Tatsuji, Ohga, Keiji, ''Biofuel Programs in China, Malaysia and Japan'', Agricultural Outlook Forum 2007</Ref>. The promotion of biofuels is attractive for many governments, especially for the ones who want to take action to fight against global warming, diminish environmental pollutions, and to set up a sustainable policy of future gobal energy requirements.
  
 +
The result of recent policy activity is that biofuels mandates now exist at the national level. "In the United States, a renewable fuel standard was enacted in 2005 that requires fuel distributors to increase the annual volume of biofuels blended up to 7.5 billion gallons (28 billion liters) by 2012 (although this target was expected to be met anyway through tax incentives). The federal government also extended a 43 cents/gallon (12 cents/liter) biodiesel tax credit for blenders through 2008"<Ref>''REN21 News and Update, Biofuels Promotion Policies'',29 November 2006, http://gsr.ren21.net/index.phptitle=Biofuels_Promotion_Policies</Ref>. It is clear that policy has played an important role in influencing on the promotion of biofuels.
  
 
==Environmental benefits and problems==
 
==Environmental benefits and problems==
 +
By the way of reducing GHGs and local pollution, biofuels can provide many benefits to the environment. For example, bioethanol is water soluble, non-toxic and biodegradable<Ref>Moreira and Goldemberg, 1999 J.R. Moreira and J. Goldemberg, The alcohol problem, Energy Policy 27 (4) (1999), pp. 229–245</Ref>. In addition, bioethanol is not as flammable as petrol, which means that it can reduce the incidence of severe vehicle fires and other daily transportation accidents. Compared to the carbon dioxide-based fuels, it is an environmentally friendly option to use hydrocarbon-based fuels.
  
 +
It is important to remember that, as Abdersib and Fergusson(2006) argue, "none of the fuels derived from biomass energy can be considered truly carbon-neutral when one bears in mind that stages of production, transportation and processing required non-renewable energy. Attention also need to be paid to crop types, especially since it is clear that some first-generation feedstocks are more applicable to biofuel production than others. <Ref>Anderson and Fergusson, 2006 G.Q.A. Anderson and M.J. Fergusson, ''Energy from biomass in the UK: sources, processes and biodiversity implications'', Ibis 148 (2006), pp. 180–183.</Ref>" Furthermore, attention should also paid to the application of fertilizers, pesticides and herbicides and the production of biofuels itself to guarantee they are not harmful to the environment in the long term.
  
==Socio-economic benefits and problems==
+
==Socio-economic benefits of biofuels==
In the United States, biofuel production has not proven to be broadly economically feasible
+
Generally, biofuels are expected to have a positive impacts in socio-economic, especially for local areas. Biofuel production is a new market for agriculture products and as a result, it offers new income options for farmers. For example, under the generous subsidies provided by the Common Agricultural policy(CPA), members of powerful European farming lobbies are guaranteed sufficient incomes in a truly competitive agricultural market<Ref>Botterill, 2006 L.C. Botterill, Soap operas, cenotaphs and sacred cows: country mindedness and rural policy debate in Australia, Public Policy 1 (1) (2006), pp. 23–36.
 +
</Ref>. It shows that the increased feedstock production will have a significant contribution in the agriculture sector. Therefore, agriculture not only plays a role in food production, but also in energy provision in the future.
  
 
==Case Study—Biofuels in China==
 
==Case Study—Biofuels in China==
Biofuels have become a broad debate in many countries' energy policies since it covers many aspects, such as energy security, food security, climate change mitigation, and international biofuel development. With 20 percent of world's population and 10 percent of its arable land, the center debate of biofuel production ins China is the conflict between food security and energy crops.  
+
Biofuel usage has become a broad debate in many countries' energy policies since it covers many areas, such as energy security, food security, climate change mitigation, and international biofuel development<Ref>Lee, Henry, Clark, William C. and Devereaux, Charan, ''Biofuels and Sustainable Development'', October 2008</Ref>. With 20 percent of the world's population and 10 percent of its arable land, China's debate on biofuel production is about the conflict between food security and energy crops. Now, the Chinese central government has taken ambitious moves to reduce petroleum products by adopting renewable energy sources.  
  
In January 2007, China’s State Forestry Administration (SFA) and the oil company PetroChina signed an agreement of developing diversity of potential energy crops, an oil-bearing plant, Jatropha. Jatropha curcas has considered as a high potential biodiesel feedstock in China since it grows on marginal land in Southwest China, and thus avoids the completion with food system. Southwest China, including Guizhou Province, Sichuan Province, and Yunnan Province, is the official target area for Jatropha production in China(see table below). Especially for Yunnan Province, it has significantly more land available for Jatropha production than neither Guizhou nor Sichuan Province. Therefore, Yunnan may be the p province capable of achieving the National Development and Reform Commission (NDRC)'s goal: to expand Jatropha plantations to 10 million mu in each Southwest province in China.  
+
In January 2007, China’s State Forestry Administration (SFA) and the oil company PetroChina signed an agreement of developing diversity of potential energy crops, such as an oil-bearing plant, Jatropha<Ref>Qi-Bao Suna, Lin-Feng Li, Yong Li, Guo-Jiang Wu, Xue-Jun Ge, ''SSR and AFLP Markers Reveal Low Genetic Diversity in the Biofuel Plant Jatropha curcas in China'', 2008</Ref>. Jatropha curcas is considered as a high potential biodiesel feedstock in China since it grows on marginal land in Southwest China and avoids the compeltition with the food system. Southwest China, including Guizhou Province, Sichuan Province, and Yunnan Province, is the official target area for Jatropha production in China(see table below). Especially for Yunnan Province, it has significantly more land available for Jatropha production than neither Guizhou nor Sichuan Province. Therefore, Yunnan may be the province capable of achieving the National Development and Reform Commission (NDRC)'s goal: to expand Jatropha plantations to 10 million mu in each Southwest province in China<Ref>Horst Weyerhaeuser, Timm Tennigkeit, Su Yufang, and Fredrich Kahrl, ''Biofuels in China: An Analysis of the Opportunities and Challenges of Jatropha Curcas in Southwest China'',© ICRAF China 2007
 +
ICRAF, Working Paper Number 53</Ref>.
 +
 
 +
Guizhou, Sichuan, and Yunnan Provinces are the poorest regions in China. Although the southwest is one of the most ecologically important regions in China, the individuals' incomes and provincial goverment revenue per person are below the national averages. Planting Jatropha could offer rural income generation and employment opportunities to improve the living standard of the local farming lobbies<Ref>''Biofuels in China: An Analysis of the Opportunities and Challenges of Jatropha Curcas in Southwest China'',© ICRAF China 2007
 +
ICRAF, Working Paper Number 24</Ref>. 
 +
 
 +
'''The Process of transferring Jatropha into biofuel'''<Ref>Jatropha: Biodiesel in India,http://www.indiadivine.org/audarya/world-review/446837-jatropha-biodiesel-india.html</Ref>
 +
[[Image:复件_Shell18.jpg]]
  
  
 
'''Estimate Current and Planned Jatropha Area in Southwest China by Province'''
 
'''Estimate Current and Planned Jatropha Area in Southwest China by Province'''
 
[[Image:Estimated_Current_and_Planned_Jatropha_Area.jpg]]
 
[[Image:Estimated_Current_and_Planned_Jatropha_Area.jpg]]
 
==Future studies==
 
The amount of subsidy, the extent of biofuel penetration into the energy market and the rate of technical progress are the key considerations in the future biofuel prospects. In this study, the only form of subsidy considered is in the form of a carbon price which may not be subsidy at all but rather a reflection of the future externality cost of GHG emission into the atmosphere. Namely, if a prospect offset 95% of the carbon created from energy equivalent amount of fossil fuel then at a US$40/MT carbon price this amounts to a US$38/MT implicit subsidy and relative to a wood price in the vicinity of US$25 to US$30/MT, this substantially offsets the purchase price to a biofeedstock user(Agiculure as a Producer and Consumer of Energy, J.Outlaw,2005).
 
Energy market penetration of biofuels is similarly important. Biofuels can penetrate when new plants are built or older plants are retrofit. New power or petroleum refining plants are needed as existing plants are retired or as demand for energy use grows(Potential for Biofuel-based Greenhouse Gas Emission Mitigation: Rationale and Potential,2004). Therefore, progress in biofeedstock yields whether at the farm or in the form of conversion ratios to energy products as energy products will be important to maintain a competitive role.
 
 
==Conclusion==
 
 
  
 
==Notes==
 
==Notes==
 
<references/>
 
<references/>

Latest revision as of 18:46, 16 December 2008

Introduction

Biofuels are considered an energy source with high potential to address problems in several areas, such as the crisis of climate change, environmental degradation, energy supply and security[1]. The use of biofuels largely depends on the availablity of different feedstocks. However, biofuels have some common features that they are all non-toxic and biodegradable, and they can reduce greenhouse gas(GHG) emissions. Recent studies from Soil and Tillage Research show that replacing fossil energy with renewable energy like biofuels is an important way of reaching climate policy goals [2].

Types of biofuels

The figure below shows that there are various opportunities for the production of biofuels. The features between biofuels and fossil fuels are quite similar. For instance, biodiesel is similar to fossil diesel, and bioethanol is similar to petrol. This is a great advantage since the existing infrastructure does not necessarily to be intensively change.


Process chains for fuel production.jpg



First-generation biofuels

PPO, biodiesel, ETBE and bioehthanol are the first-generation biofuels. They are generally produced by the action of microorganisms and enzymes through the fermentation of any biological feedstock[3]. Bioethanol, the most common biofuel feedstock, offers the greatest short-term bioful potential today since the conversion is widely developed and approved in practice [4]. Although the first-generation biofuels are different in properties, technical requirements, economical aspects and potential usages, they can all contribute to guarantee long-term sustainability.


Second-generation biofuels

Second-generation biofuels are derived from feedstocks, which are not traditionally used for human consumption. They include BTL fuels and ethanol from lingo-cellulose. These products are not yet commercial available since their conversion technologies are not improved enough as products of first-generation biofuels. However, second-generation biofuels are considered to be more environmental healthy and produce less GHGs than first generation biofuels. The reason is that they can make use of the vast majority of feedstock in the process of production and avoid the waste inherent in the production of first generation biofuels[5]. Second-generation biofuels can not only help solve this waste problem, but also can supply a larger proportion of our fuel supply sustainably, affordably, and with greater environmental benefits.



The figure below focuses on the pathways of biofuel production. It shows that feedstocks sources can be divided into animal fats, oil crops, sugar plants, starchy plants, cellulosic biomass and wet biomass. During the different processes, such as refining, extraction, hydrolysis and fermentation etc., they can be transformed into liquid or gaseous biofuels.

Pathways of Different biofuels[6]

Pathways of different biofuels.jpg

Current biofuel promotion policies

A turning point for biofuels policies occurred in 2005–06, when several countries dramatically stepped up targets and mandates for biofuels to make a great promotion of their use[7]. The promotion of biofuels is attractive for many governments, especially for the ones who want to take action to fight against global warming, diminish environmental pollutions, and to set up a sustainable policy of future gobal energy requirements.

The result of recent policy activity is that biofuels mandates now exist at the national level. "In the United States, a renewable fuel standard was enacted in 2005 that requires fuel distributors to increase the annual volume of biofuels blended up to 7.5 billion gallons (28 billion liters) by 2012 (although this target was expected to be met anyway through tax incentives). The federal government also extended a 43 cents/gallon (12 cents/liter) biodiesel tax credit for blenders through 2008"[8]. It is clear that policy has played an important role in influencing on the promotion of biofuels.

Environmental benefits and problems

By the way of reducing GHGs and local pollution, biofuels can provide many benefits to the environment. For example, bioethanol is water soluble, non-toxic and biodegradable[9]. In addition, bioethanol is not as flammable as petrol, which means that it can reduce the incidence of severe vehicle fires and other daily transportation accidents. Compared to the carbon dioxide-based fuels, it is an environmentally friendly option to use hydrocarbon-based fuels.

It is important to remember that, as Abdersib and Fergusson(2006) argue, "none of the fuels derived from biomass energy can be considered truly carbon-neutral when one bears in mind that stages of production, transportation and processing required non-renewable energy. Attention also need to be paid to crop types, especially since it is clear that some first-generation feedstocks are more applicable to biofuel production than others. [10]" Furthermore, attention should also paid to the application of fertilizers, pesticides and herbicides and the production of biofuels itself to guarantee they are not harmful to the environment in the long term.

Socio-economic benefits of biofuels

Generally, biofuels are expected to have a positive impacts in socio-economic, especially for local areas. Biofuel production is a new market for agriculture products and as a result, it offers new income options for farmers. For example, under the generous subsidies provided by the Common Agricultural policy(CPA), members of powerful European farming lobbies are guaranteed sufficient incomes in a truly competitive agricultural market[11]. It shows that the increased feedstock production will have a significant contribution in the agriculture sector. Therefore, agriculture not only plays a role in food production, but also in energy provision in the future.

Case Study—Biofuels in China

Biofuel usage has become a broad debate in many countries' energy policies since it covers many areas, such as energy security, food security, climate change mitigation, and international biofuel development[12]. With 20 percent of the world's population and 10 percent of its arable land, China's debate on biofuel production is about the conflict between food security and energy crops. Now, the Chinese central government has taken ambitious moves to reduce petroleum products by adopting renewable energy sources.

In January 2007, China’s State Forestry Administration (SFA) and the oil company PetroChina signed an agreement of developing diversity of potential energy crops, such as an oil-bearing plant, Jatropha[13]. Jatropha curcas is considered as a high potential biodiesel feedstock in China since it grows on marginal land in Southwest China and avoids the compeltition with the food system. Southwest China, including Guizhou Province, Sichuan Province, and Yunnan Province, is the official target area for Jatropha production in China(see table below). Especially for Yunnan Province, it has significantly more land available for Jatropha production than neither Guizhou nor Sichuan Province. Therefore, Yunnan may be the province capable of achieving the National Development and Reform Commission (NDRC)'s goal: to expand Jatropha plantations to 10 million mu in each Southwest province in China[14].

Guizhou, Sichuan, and Yunnan Provinces are the poorest regions in China. Although the southwest is one of the most ecologically important regions in China, the individuals' incomes and provincial goverment revenue per person are below the national averages. Planting Jatropha could offer rural income generation and employment opportunities to improve the living standard of the local farming lobbies[15].

The Process of transferring Jatropha into biofuel[16] 复件 Shell18.jpg


Estimate Current and Planned Jatropha Area in Southwest China by Province Estimated Current and Planned Jatropha Area.jpg

Notes

  1. Runar Brännlund, Bengt Kriström, Tommy Lundgren and Per-Olov Marklund, The Economics of Biofuels,2007
  2. R. Horn, M. Kutílek, R. Lal, J. Tisdall,Soil and Tillage Research , Volume 61, Issues 1-2, Pages77-92, August 2001,
  3. Dominik Rutz & Rainer Janssen , Biofuel Technology Handbook,page39, 2008
  4. Sergey Zinoviev, Sivasamy Arumugam, and Stanislav Miertus,Biofuel Production Technologies, Institute of Energy and Environment, Leipzig, Germany and Paolo Fornasiero, University of Trieste, Italy, November 2007
  5. Deurwaarder, E.P., 2005. Overview and Analysis of National Reports of the EU Biofuel Directive: Prospects and Barriers for 2005. ECN (Energy Research Centre of the Netherlands) http://www.ecn.nl/docs/library/report/2005/c05042.pdf
  6. Dominik Rutz & Rainer Janssen , Biofuel Technology Handbook,page39, 2008
  7. Koizumi, Tatsuji, Ohga, Keiji, Biofuel Programs in China, Malaysia and Japan, Agricultural Outlook Forum 2007
  8. REN21 News and Update, Biofuels Promotion Policies,29 November 2006, http://gsr.ren21.net/index.phptitle=Biofuels_Promotion_Policies
  9. Moreira and Goldemberg, 1999 J.R. Moreira and J. Goldemberg, The alcohol problem, Energy Policy 27 (4) (1999), pp. 229–245
  10. Anderson and Fergusson, 2006 G.Q.A. Anderson and M.J. Fergusson, Energy from biomass in the UK: sources, processes and biodiversity implications, Ibis 148 (2006), pp. 180–183.
  11. Botterill, 2006 L.C. Botterill, Soap operas, cenotaphs and sacred cows: country mindedness and rural policy debate in Australia, Public Policy 1 (1) (2006), pp. 23–36.
  12. Lee, Henry, Clark, William C. and Devereaux, Charan, Biofuels and Sustainable Development, October 2008
  13. Qi-Bao Suna, Lin-Feng Li, Yong Li, Guo-Jiang Wu, Xue-Jun Ge, SSR and AFLP Markers Reveal Low Genetic Diversity in the Biofuel Plant Jatropha curcas in China, 2008
  14. Horst Weyerhaeuser, Timm Tennigkeit, Su Yufang, and Fredrich Kahrl, Biofuels in China: An Analysis of the Opportunities and Challenges of Jatropha Curcas in Southwest China,© ICRAF China 2007 ICRAF, Working Paper Number 53
  15. Biofuels in China: An Analysis of the Opportunities and Challenges of Jatropha Curcas in Southwest China,© ICRAF China 2007 ICRAF, Working Paper Number 24
  16. Jatropha: Biodiesel in India,http://www.indiadivine.org/audarya/world-review/446837-jatropha-biodiesel-india.html