Biofuels

Biofuels is a blanket term for fuels derived from recently-deceased biological materials. Biofuels exist as liquids, solids and gases and are most commonly used to power vehicles, heat homes and fuel cooking stoves. They are often promoted as environmentally friendly alternatives to fossil fuels, but have faced significant opposition worldwide due to concerns over their sustainability and overall viability. Biofuels produced in the traditional manner are often referred to as " first generation biofuels," those made from sugars, starches, fats or oils using conventional techniques. ¹ Newer technologies focus on feedstocks from non-food sources and the non-edible parts of food crops.

Liquid biofuels

Liquid biofuels can be produced from a wide variety of feedstocks to be used in conventional engines. They can be divided into two general categories: biofuel derived from alcohols and biofuel derived from fats and oils.

Life Cycle of Medium to Large Scale, Agri-based Biofuels

Source: DOE EERE Author: DOE. Permission: No Copyright.

Bio-alcohols

Ethanol is a volatile, flammable, and colorless alcohol derived from sugars and starches in biomass such as sorghum, wheat, rice, or yard clippings; in the United States it is typically made from corn. Ethanol can be combined with gasoline in varying concentrations, usually to be used in gasoline engines. E10, which contains 10% ethanol and 90% unleaded gasoline, can be used in almost all conventional gasoline engines and is covered under warranty by every major U.S. automobile manufacturer. E85, or 85% ethanol, is considered an alternative fuel under the Energy Policy Act of 1992.² This blend can only be used in E85-capable flexible fuel vehicles (FFVs), which are available in a variety of models from U.S. and foreign automakers.

Ethanol produces fewer emissions of CO2 and benzene than gasoline, but its emissions and energy balance vary based on feedstock. According to the EPA corn-based ethanol generates about 30 percent more energy than the fossil fuel energy used to produce it, and over its life cycle reduces petroleum use more than 90% over gasoline.³ Still, other ethanol feedstocks may offer significant environmental benefits over corn. For example the World Bank estimates that sugarcane biodiesel produced in Brazil reduces gasoline emissions by about 90 percent, whereas US corn ethanol lowers gas emissions by 10-30 percent.⁴

Biobutanol can be produced from any type of biomass. It offers advantages over ethanol as it has a higher energy density, can be blended with gas in any concentration to be used in conventional gasoline engines, and can be transported through existing pipeline infrastructure.⁵ While biobutanol has not been produced successfully on a large scale the technology has received significant investment, specifically through a joint venture being undertaken by the DuPont corporation and British Petroleum (BP).⁶

Cellulosic ethanol has the same chemical composition as first-generation ethanol but is based from the cellulose and hemicelluloses in woody fibers. Cellulosic technology has strong appeal since cellulose presents a ubiquitous and renewable resource, but it is not yet in wide use.⁷

Bio-oils

A mobile, small-scale biodiesel processing unit.

Source: Piedmont Biofuels Cooperative http://www.biofuels.coop. Author: Lindsay Vacek. Permission: Permission granted by owner.

Biodiesel is a cleaner-burning alternative to petroleum diesel that can be produced from virtually any fat or vegetable oil. Through a chemical process called transesterification, heavy glycerol molecules are swapped with a lighter alcohol (most often methanol) under very high temperatures, which lightens the fuel so that it runs through any ignition-compression vehicle without modifications to the engine. Pure biodiesel (B100) can be blended with petroleum diesel in any proportion.⁸ In the United States biodiesel has traditionally been made from soybeans, but animal fats and other agri-crops such as rapeseed, flax and canola have become increasingly common. In countries across Central and South America, Asia and Africa, biodiesel may also be produced from Jatropha oil from the Jatropha Csucas tree.

Biodiesel is widely available in many European countries as B100, but due in large part to state mandates it is most commonly sold in the United States as B2 (2% biodiesel) or B5 (5% biodiesel). Biodiesel must comply with a strict set of standards (ASTM D7651)⁹ in order to be sold for on-road use in the United States.

Straight vegetable oil, including "virgin" oils or recycled oils, can be converted into biodiesel or used in diesel engines that have undergone a conversion process. The conversion creates a second tank intended for vegetable oil, while the first tank holds diesel or biodiesel fuel. The driver starts the car drawing fuel from the first tank, then switches to the second tank when the engine has heated and the oil has sufficiently thinned.¹⁰

Algal biofuel can be derived from aquatic plants raised in open ponds or incubating units. Algae produces vastly more oil per acre than traditional feedstocks; the limiting factor is actually access to carbon dioxide. As a result, current technologies face significant cost limitations. The DOE estimates that algal biofuel produced with currently-available technology would cost over $8 per gallon, while the price of soy biodiesel today hovers around $4 per gallon.¹¹

It is generally agreed that biodiesel fuel offers a superior emissions profile to standard petroleum diesel. According to the National Renewable Energy Laboratory (NREL), a vehicle powered by B20 reduces life-cycle petroleum consumption by 19%, carbon dioxide emissions by 16%, and further reduces hydrocarbon emissions by 20%.¹² Higher blends mean even greater emissions reductions. However there have been questions concerning biodiesel's nitrogen oxide (NOx) emissions, with studies by EPA and NREL showing both higher and lower NOx levels as compared to diesel emissions.¹³

Biofuel from solids and gases

Solid Biofuel refers to any type of solid biomass or other matter that can be burned directly, such as wood, agricultural waste, energy crops and biochar. Burning solids releases heat that can be harnessed for energy, as well as liquids and solids that can be used as biofuel.

Biogas can be produced through the anaerobic digestion of biodegradable materials such as biomass, manure or sewage. It consists mostly of methane and carbon dioxide mixed with other trace gases, and can be used to generate electricity or compressed for use as a transportation fuel. Biodigesters are often viewed as ideal partners for farms that produce animal waste, as the digester doubles as an energy source and sanitation device.¹⁴

Syngas ("synthetic gas") is produced by heating and compressing any material that contains carbon, such as biomass or coal, and is comprised of carbon monoxide, carbon dioxide and hydrogen.¹⁵ It can be made into transportation fuels such as methane gas or synthetic diesel fuel, and the ash that is generated as a sidestream can be used as fertilizer.¹⁶

Benefits

While biofuels vary by type, it is generally agreed that many have significant advantages:

Most biofuels are biodegradable, nontoxic and derived from renewable materials.
Biofuels may enhance agricultural production, which may be of particular use in less developed areas.
Biofuels offer a means of domestic energy production that can enhance regional energy security.
Biofuel production offers a way to both produce and consume fuel on a local level, both for efficiency and as a local economic stimulus. Such locally driven, small to medium-scale operations have the potential to be the most economical and reliable energy sources for poor communities.¹⁷

Drawbacks and limitations

Despite their varied benefits, biofuels are also the subject of much debate and face significant limitations in the fuel marketplace:

Competition for Resources
Biofuels produced from agricultural products can drive a competition for common resources like land and water. It is likely that biofuel production has destabilized the costs of staples like corn, wheat and soy that are used as feedstocks. Such price increases likely have the greatest impact on poor communities who are net buyers of staple crops.¹⁸

Deforestation

Agricultural biofuel production may be contributing to the worsening problem of deforestation. In fact U.S. biofuel incentives have been blamed for record deforestation in Indonesia and the Amazon, where trees are being burned away in record numbers for soy farming.¹⁹ Forests serve as important carbon sinks that help regulate global climate -- in fact, recent studies have shown that tropical forests are absorbing 18% of the CO2 emitted annually through fossil fuel consumption.²⁰

Use of non-renewable resources

Some biofuel conversion processes use nonrenewable resources in production or distribution. For example, ethanol is usually made with natural gas, and biodiesel is produced with methanol.²¹ In addition, fossil fuels are usually used to truck the biofuel to market.

Infrastructure Limitations

Biofuels often require different infrastructure networks than are typically used for petroleum, which can present significant limitations. For example, conventional gasoline engines can only use 10% ethanol, and even FFV engines must use ethanol mixed with at least 15% gasoline.²² Because it is more corrosive and water-affinitive than gasoline, ethanol also requires modifications in pipe infrastructure.²³

Goverment initiatives

Biofuels have received much legislative and programmatic support worldwide in nations of all levels of economic development. Many countries around the world, as well as individual states in the U.S., actively encourage biofuel use as part of their renewable energy portfolio. In the United States most biofuel legislation falls under the category of "mandated fuel use, tax incentives, loan and grant programs, [or] certain regulatory requirements."²⁴ The Renewable Fuel Standard (RFS), a particularly ambitious federal mandate, will increase the volume of renewable fuel required to be blended into standard petroleum from 9 billion gallons in 2008 to 36 billion gallons by 2022.²⁵ Other U.S. agencies have shown marked support for biofuels; the U.S. Department of Energy (DOE), for example, is implementing an aggressive plan towards the research and development of various biomass technologies from 2007 through 2017.²⁶ Many other nations have or are in the works of enacting biofuel legislation. Some examples include:

Brazil has a production mandate of 7 Billion gallons per year, of which 2 billion gallons per year are a surplus.²⁷
Thailand has imposed an E10 mandate and is working with Shell Oil to produce more flex fuel vehicles.²⁸
China is experimenting with mandates in some regions.
India has an E10 mandate dating from October 2008.²⁹
Latin America and the Caribbean region are moving towards an E10 mandate with support from the Inter-American Development Bank's Sustainable Energy and Climate Change Initiative.³⁰

Roundtable on Sustainable Biofuels

The Roundtable on Sustainable Biofuels (RSB) was initiated in 2007 to create a standard for biofuels production and processing that would ensure environmental, social, and economic sustainability, while reducing the impact of biofuels on global climate change. RSB principles and criteria are currently being developed through a consultative, multi-stakeholder process, with public comment periods following the ISEAL best practices. A key provision in the RSB 2008 draft is:

Principle 3: Biofuels shall contribute to climate change mitigation by significantly reducing GHG emissions as compared to fossil fuels. Standard methods for measuring the life-cycle GHG impact of biofuels (Life Cycle Analysis, LCA) will be developed under this principle to even the playing field and remove any subjectivity from the process. (RSB 2009)²²

The RSB recognizes that GHG impacts of biofuels production exist both on the farm, where producers control practices, and off the farm, where market forces may compromise compliance with Principle 3. The current version of the standard focuses on practices that a producer can actually control. Producers are advised on strategies to minimize the risk of iLUC by:

• Maximizing use of waste and residues as feedstocks; marginal, degraded or previously cleared land; improvements to yields; and efficient crops;
• International collaboration to prevent detrimental land use changes; and
• Avoiding the use of land or crops that are likely to induce land conversions resulting in emissions of stored carbon.

The RSB also attempts to deal with biological diversity, conservation and expects to include a deforestation cut-off date in the final standard.

Round Table on Responsible Soy & Soy Working Group
Better Sugar Initiative (BSI)

The Better Sugar Initiative (BSI) was initiated in 2005, but is still in an early stage of development compared to the other roundtables discussed here. Principles have been drafted, but criteria have not, though at the time this was written, draft criteria were expected to be released soon. The BSI is a “global multi-stakeholder non-profit initiative dedicated to reducing the environmental and social impacts of sugar cane production” and is following the ISEAL best practices (http://www.bettersugar.org). Some innovative ideas are being considered by the board, including having buyers purchase the sustainability certificate in addition to the sugar in order to help offset some of the cost of certification.
Forest Stewardship Council (FSC)

Footnotes

1. : .UK Biofuel Information Site. First Generation Biofuels. Retrieved on 13 January 2009.

2. : Robyn Kenney, The Encyclopedia of the Earth. November 18, 2008. Energy Policy Act of 1992, The United States.Retrieved on 13 January 2009.

3. : US EPA SmartWay Grow & Go Program. EPA420-F-06-068, October 2006 "Frequent Questions". Retrieved on 20 January 2009.

4. : Biofuels, the Promise and the Risks. World Development Report 2008: Agriculture for Development. Biofuels: The Promise and the Risks, pg. 2. Retrieved on 15 January 2009.

5. : Green Car Congress. JBEI Researchers Engineer Yeast to Produce n-Butanol, 6 December 2008. Retrieved on 10 February 2009.

6. : DOE Alternative Fuels and Advanced Vehicles Data Center. Biobutanol Production. Retrieved on 10 February 2009.

7. : Rick Newman. The US News and World Report, 11 January 2008. "Cellulosic Ethanol". Retrieved on 10 February 2009.

8. Infosheet: Biodiesel Use On-farm?Ministry of Argriculture,Food&Rural Affairs, Ontario.ca.

9. : ASTM D6751-08 Standard Specification for Biodiesel Fuel Blend Stock (B100) for Middle Distillate Fuels

10. : Lilia Scott. EHow.com: "How to Convert a Car to Run on Vegetable Oil." Retrieved on 10 February 2009.

11. : Department of Energy, Energy Efficiency and Renewable Energy. Biomass Program: Algal Biofuels. Retrieved on 10 February 2009.

12. : Bob McCormick, The National Renewable Energy Laboratory: Effects of Biodiesel on NOx Emissions . ABR Working Group, June 8, 2005. Retrieved on 1 February 2009.

13. : Bob McCormick, The National Renewable Energy Laboratory: Effects of Biodiesel on NOx Emissions

14. : Gerald Knaauf, et al. The Challenge of Sustainable Bioenergy: Balancing climate protection, biodiversity and development policy, a Discussion Paper, p.5. Retrieved on 10 February 2009

15. : UK Biofuel Information Site. What is Syngas? Retrieved on 10 February 2009.

16. : Planet Green. Green Glossary: "Gasification". 26 January 2009. Retrieved on 10 February 2009.

17. : United Nations report on Biofuels. Sustainable Bioenergy: A Framework for Decision Makers, p. 7-9.

18. : World Development Report 2008: Agriculture for Development Biofuels: The Promise and the Risks. Retrieved on 10 February 2008.

19. : Rhett A. Butler, 17 January 2008. U.S. biofuels policy drives deforestation in Indonesia, the Amazon. Mongabay.com Environmental Science and Conservation News. Retrieved on 10 February 2009.

20. : David Adam, The Guardian, 18 February 2009, "Fifth of World Carbon Emissions Soaked up by Extra Forest Growth, Scientists Find". Retrieved on: 19 February 2009.

21. : Ethanol boom may boost U.S. natural gas prices. Reuters News Agency, 19 April 2007. Retrieved on 25 January 2009.

22. : Christine Gable and Scott Gable, "From Gasoline to Alcohol - E85 as a Transitional Fuel". About.com. Retrieved on 30 January 2009.

23. : American Petroleum Institute, Association of Oil Pipelines. In The Pipe: Increased Ethanol Use Creates Challenges. Retrieved on 10 February 2009.

24. Brent D. Yacobucci, 5 January 2009. Biofuels Incentives: A Summary of Federal Programs. Congressional Research Service, p.2. Retrieved on 13 January 2009.

25. : The Environmental Protection Agency, Fuels and Additives. "The Renewable Fuel Standard Program." Retrieved on 25 January 2009.

26. : The United States Department of Energy Biomass Program. "About the Program." Retrieved on 25 January 2009.

27. Fact Sheet: Why Ethanol and Biodiesel Alone Can Not Achieve 35 Billion Gallons of Petroleum Displacement by 2017，Natrual Gas Vehicles for America.

28. Thailand to mandate 2% palm oil biodiesel next year, Biopact.

29. India to Mandate E10, Green Car Congress.

30. E10: Use of Musa Biodiversity to Improve Livelihoods, IPGRI Project Portfolio.