Advanced biofuels. 1. What are advanced biofuels?

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1 TM Advanced biofuels In the debate on climate change and reduction of greenhouse gases emissions, first, second or even third generation biofuels are frequently mentioned. The use of the concept of different generations can be in itself confusing. However it should be noted that it is a simplifying term used to categorise what is in reality a diverse range of technologies and feedstock types. Advanced biofuels (2 nd and 3 rd generations) offer the chance to have a better environmental impact and are aimed at the use of non-food feedstock and residues of food feedstock. As these advanced biofuels come to the market they will coexist with first generation biofuels, and as technology improves their market share will gradually increase. The wide spread adoption of first generation biofuels, using technology that is well known today, is necessary to speed up the development and market introduction of advanced biofuels. This in turn will help address scale-up and distribution issues and create a broader market. 1. What are advanced biofuels? Advanced biofuels are those biofuels that have the potential to be produced in significant quantities and deliver a significant lifecycle GHG emission saving while minimizing competition for agricultural land. They also have the potential to be economically competitive in terms of cost with conventional fossil fuels just as ethanol from sugar cane in Brazil is today. Advanced biofuels may be produced for instance from waste, agricultural (food crops) residues, nonfood (ligno) cellulosic biomass, crops grown on marginal land and algae. 1.1 Bioethanol & biobutanol Bioethanol is a biofuel derived by the fermentative transformation of sugars (glucose, starch or biomass). It is a full substitute for gasoline in so-called flexi-fuel vehicles in various blending concentrations up to 100%. In smaller blend quantities it can be used in conventional, unmodified vehicles.

2 Process flow diagram for ethanol production from ligno-cellulose Biomass Pre-treatment Hydrolysis Fermentation Product Separation Grinder Cellulose, Hemicellulose, Lignin Glucose & Pentose Monomers, Lignin Fermentation broth Ethanol Co-products Energy Energy Enzymes Yeast, Bacteria Source: International Energy Agency, Gaps in the research of second generation transportation biofuels Residue (process fuel) Biobutanol is an alcohol belonging to the high alcohol branch and can be used as fuel. Like bioethanol, biobutanol is produced by fermentation and uses the same feedstocks. Therefore a bioethanol plant can be converted into a biobutanol plant and vice versa. Biobutanol can be mixed with gasoline more easily than bioethanol and can be used at higher blends in current engines 1. The key difference between the first and the advanced generations of bioethanol is the feedstock: first generation is mostly based on sugar (sugar beet, sugar cane) or starch (corn, wheat, sorghum) derived from food crops, whereas advanced generation biofuels are based on ligno-cellulosic materials such as agriculture and forest residues, industrial wastes, or dedicated crops. These include, for example, switch grass, short rotation coppice or new varieties of corn or sugar cane 2 which generally produce more biomass. From a technological point of view, advanced bioethanol is more complex to produce as ligno-cellulosic biomass must undergo a pre-treatment before the enzyme treatment that will release the sugar for fermentation into ethanol. 1.2 Biodiesel Biodiesel is usually produced from oilseed rape, soy and palm oils. Improved production processes allow the use of alternative to feedstocks such as used cooking oils, animal fats and algae. Alternative non-food oil crops such as jatropha may also serve as a feedstock for biodiesel. Biodiesel (or FAME 3 ) is produced through trans-esterification (a chemical reaction) of vegetable oils, but also residual oils and fats. With minor engine modifications, it can be used either as a full substitute for diesel or blended into traditional diesel up to 20%. Using hydrogenation (the catalytic reaction of oils and fats with hydrogen), novel processes are being developed as an alternative to the well established trans-esterification procedure. This process can produce a high quality syndiesel from low quality feedstocks like tallow, used cooking oils and fats 4-5. A more recent process for converting complete biomass (from for example crop residues or wood) into a biodiesel is the BTL (biomass to liquid) technology. This uses gasification or pyrolysis (chemical decomposition of organic materials by heating in the absence of oxygen or any other reagents) to transform biomass into syngas (synthetic gas) and retransform it into diesel or gasoline 6.

3 2. What is the status of advanced biofuels technology development? Technologies Laboratory Pilot Plant Demonstration Plant Market Sugar/starch ethanol Ligno-cellulosic ethanol Biobutanol Jatropha biodiesel BTL Algae biodiesel It should be noted that the technology development status (specially for the demonstration stage) is not homogenous in different part of the world. For instance ligno-cellulosic ethanol demonstration already exist in the U.S. and China. 2.1 Bioethanol and biobutanol A number of demonstration plants to produce ligno-cellulosic ethanol are now operating or under construction in the EU and in North America 7. Regular updates on the development of production facilities are provided by the International Energy Agency on its website 8. Pre-treatment effect on ligno-cellulosic material. Enzyme technology for making ligno-cellulosic ethanol will be available soon 9. Full scale commercialisation is expected to happen over the coming years, most probably before Source: (From Hsu et al., 1980) / International Energy Agency, Gaps in the research of second generation transportation biofuels Biobutanol from fermentation was a process used in the first half of the 20th century. Though neither particularly efficient nor competitive with petrochemical processes, some production plants remained in China which are now reactivated to produce biobutanol fuel. With higher oil prices and environmental concerns several groups are attempting to increase the biobutanol yield of the process to improve its competitiveness. Two large companies 10 have developed plans to convert an existing bioethanol plant for biobutanol production as soon as the technology is available. They are planning a pilot plant to further develop the technology. It is expected to be operational in 2010.

4 2.2 Biodiesel Jatropha is a tropical and subtropical plant which contains more than 30% oil 11. It is a potential new feedstock for the production of non-edible plantoils for energy use. It is currently grown and tested in countries such as India, Indonesia, Brazil and several African countries. In the future, it may become an attractive alternative to established oil crops, since it is an environmentally flexible crop with reduced water needs and hence has potential to become a sustainable source of bioenergy production. The first crude jatropha oil was produced in 2008 and commercial fuel is expected become available in 2009/ With new processes under development, it is now possible to reuse glycerol 13 a by-product of the current biodiesel production process for biodiesel production. Biotransformation of glycerol into oils by means of algae and yeasts 14 as well as the reintroduction of the residual glycerol in the biodiesel synthesis process means that 100% of the feedstock is used 15. This process should be commercially available within the next five years. The development of BTL (biomass-to-liquid) for the production of synthetic diesel is most advanced in Europe, particularly in Germany. Industry is 16 expected to have its first industrial scale production plant operational within the next three to five years. The use of algae for the production of biomass and oils for biofuels is still in its early stages 17. In the production process, algae can be cultivated in open ponds to capture carbon dioxide from the air. This CO 2 can also be processed as a waste product from power station, which is captured via closed glass or plastic tube circulation fermentors. 3. What are the advantages of advanced biofuels? Advanced biofuels mitigate climate change 18 by allowing further GHG emission reductions. For example, bioethanol produced from wheat straw only release 20g CO ² /km along its life cycle while petrols release on average 163g CO ² /km 19. Advanced biofuels reduce pressure on food crops by developing alternative fuels from non food feedstock and agricultural residues. Moreover, they can use waste products as feedstocks, reducing the amount of agricultural waste to be landfilled or disposed of by other mechanisms. Advanced biofuels reduce pressure on land use 20 as they require less farmland to grow the same amount of feedstock. For example, lignocellulosic ethanol is produced using the whole crop instead of only easily accessible sugars and starch. Jatropha, can help avoid land competition as it can be grown on marginal land that is unsuitable for food crops. In the future, biodiesel from algae could further aleviate pressure on land as it could be produced in fermentors. Advanced biofuels produce useful by-products. Like first generation biofuels by-products, these fuels can be used in other chemical processes, burned for heat and power or used as fertilizer. As an example, biodiesel from jatropha can be burnt in a standard diesel car while the residual press cake can also be processed into biomass to power electricity plants. In mature plantations, every hectare can currently produce between 1,5 and 2 tonnes of oil and 3-4 tonnes of biomass. Trials are also underway to convert the residual meal from the crushing process into a valuable protein source for animal feed use. 21 Advanced biofuels are more flexible to market preference (diesel vs gasoline). With the BTL technology, syngas can be used to produce either diesel or gasoline 22. Equally algae can be used to produce biodiesel through its oils and bioethanol from its biomass. Lastly biobutanol can be used as both gasoline and diesel substitutes. Biofuels CO 2 profile saving by feedstock 20 Bioethanol Feedstocks examples Corn (US) Production cost /MWh 46 CO 2 profile** 90 Wheat (EU) Sugar beets (EU) Sugarcane (Brazil) Wood* Other lignocellulosic feedstock* Biodiesel Rapeseed (EU) Soy bean (US) Syndiesel BTL* (Fischer-Tropsch) Second generation biofuel * Expected cost in 2020 ** Percentage of CO 2 release for the corresponding fossil fuel (well to wheel) Source: McKinsey; Eucar/Concawe/JRC well-to-wheels study, 2003, 2005

5 4. What are the challenges for advanced biofuels? 23 Advanced biofuels provide promising opportunities which several companies have already embraced in order to invest for the future. These investments aim notably to reduce the relatively high production costs, to improve the efficiency of biomass to biofuels conversion and to reduce the costs of biomass transportation, notably via a better biomass logistics system. Various technologies, which can optimise the use of crops or provide more efficient biomass pre-treatment are being investigated. Pre-treatment of biomass is technically challenging and constitutes a large part of the processing cost. In the case of enzyme-based ligno-cellulosic ethanol for example, a package of enzymes/microbes will be required for hydrolysis (breakdown of cellulose to sugar) and fermentation; which adds significant process costs. The commercialisation of biofuels and advanced biofuels will also mean that infrastructure to harvest, transport, store and refine biomass must be developed. To avoid unnecessary transportation, biofuels and advanced biofuels production could be coupled with the production of other biobased products in integrated biorefineries. An integrated biorefinery is a cluster of bio-industries, using a variety of different technologies to produce chemicals, biofuels, food ingredients and power from biomass raw materials. The benefits of an integrated biorefinery are numerous. The development of alternative feedstocks and cost-competitive conversion processes will mean cheaper and more environmentally sustainable options for integrated biorefineries. This will also allow biorefineries to spread over a wider geographical region. Source: Novozymes

6 5. How can biotechnology contribute to advanced biofuels? Biotechnology is currently one of the most effective and innovative technologies we have to meet European targets for biofuel use, while reducing the adverse environmental impacts of transport and limiting increased cultivated land. Industrial biotechnology with its competitive, clean and clever use of biobased technologies can play a key role in making biofuels more sustainable. As an example, biocatalyzed bioethanol production from ligno-cellulosic biomass uses enzymes that convert (hemi)cellulose and organic agricultural waste to sugar. Innovation in industrial biotechnology, especially in the development of enzymes that can convert (hemi)cellulose with improved efficiency, is key to the development of advanced biofuels. These enzymes will reduce advanced biofuels production costs and make them cost-competitive with petrol-based fuels (to a varying degree depending on the price of oil per barrel). The challenges from agricultural requirements to produce food and energy can only be met if we use all options available for increasing productivity and safeguarding harvests. Innovative crop protection products and plant biotechnology provide solutions to reduce the energy consumption in agriculture while conserving natural resources and contributing to mitigate the effect of climate change. Modern plant biotechnology and plant breeding methods have a key role to play in the quest to increase yields and quality in a sustainable way. Plant biotechnology also offers solutions to address technical requirements through the development of crops that produce more fermentable carbohydrates or higher yields.one notable example is modern canola hybrid oil-seed which can produce up to percent higher yields on average than those achieved with regular hybrid varieties. References and Further Reading 1 British Petroleum and DuPont: Biobutanol factsheet bp.com/liveassets/bp_internet/globalbp/staging/global_assets/ downloads/b/bio_biobutanol_fact_sheet_jun06.pdf 2 Fernando Reinach, Votorantim Ventures, Brazil presentation at IB World Congress, Toronto Fatty Acid Methyl Esters Liquid Transport Biofuels - Technology Status Report, nnfcc.co.uk/metadot/index.pl?id=6597&isa=dbrow&field_ name=file&op=download_file Novozymes 10 British Petroleum and DuPont 11 GEXSI Global market study on Jatropha 12 D1 Oils FACT Fuel from Agriculture in Communal Technology GEXSI Global market study on Jatropha kg of glycerol are produced for 1 ton of biodiesel, theglycerolchallenge.org/ 14 Neuron BPH, 15 Institut de Ciència i Tecnologia (IUCT), 16 Choren See also EuropaBio s factsheet: Industrial biotechnology and climate change ClimateChange_IB.pdf 19 Liquid Transport Biofuels - Technology Status Report, nnfcc.co.uk/metadot/index.pl?id=6597&isa=dbrow&field_ name=file&op=download_file 20 See also EUropaBio s factsheet: Biofuels and land use: europabio.org/biofuels/land%20use_biofuels%20factsheet.pdf 21 GEXSI Global market study on Jatropha Claims and Fact on Jatropha curcas L., Wageningen University Facts_on_Jatropha_-WUR 22 Source: International Energy Agency, Gaps in the research of second generation transportation biofuels. 23 See also EuropaBio s facsheet: Biotechnology making biofuels sustainable Brochure.pdf Other factsheets in the series available on: Biofuels/Biofuels_about.htm TM For further information please contact: EuropaBio EuropaBio s (the European Association for Bioindustries) mission is to promote an innovative and dynamic biotechnology-based industry in Europe. EuropaBio s corporate and associate members operate worldwide. Avenue de l Armée 6 B-1040 Brussels Tel : Fax : ib@europabio.org May 2009