The biocarburants are Carburant S produced starting from renewable organic materials and not-fossils. This production can be done starting from a whole of varied techniques: production of oil, alcohol by alcoholic Fermentation of sugars or Starch hydrolized, gas fuels obtained starting from biomass vegetable or animal (dihydrogene or methane), or containing hydrocarbon solids like the Charcoal.
To use the biocarburants in the engines, two approaches are possible:
- Is one seeks to adapt biocarburant it (by chemical conversion to obtain Biodiesel for example) to engines designed to function with derivatives of oil; it is the currently dominant strategy but it does not have the best energy assessment nor environmental.
- Is one seeks to adapt the engine to biocarburant natural, not chemically transformed. Several companies specialized in these adaptations. Substitution can be total or partial. The Moteur Elsbett functions for example entirely with the pure Plant oil. This strategy allows a local production and more decentralized fuels.
DenominationThe term “biocarburant” (of the Greek bios , which means life, alive , and of Latin carbo , who means coal and evokes the carbon ) means that this fuel is obtained starting from organic materials.
Il poses problem in the French-speaking countries of Europe because the term “bio” indicates there the products of the Organic farming (Danone was thus obliged to re-elect its yahourt Bio in Activia ). Some thus prefer to employ the word agrocarburant or agro-biocarburant for the products resulting from agriculture. For example in the scientific press of Popularization in France, the magazine Science and Avenir employs the two words, just like the Grenelle of the environment in 2007, others preferring the word “biocarburant” which remains majority.
The search engines of the Internet show that the element préfixale " agro-" (drawn from the Greek agros: field) is used more and more. Associated with the carburizing substantive, it indicates the fuels more precisely resulting from the Agriculture, differentiating them of the not-agricultural biocarburants (for example the Méthane resulting from waste, or the biocarburants produces starting from wood). There can remain one ambiguitié of denomination for wood resulting from the Agroforesterie (energy valorization of the sizes of hedges and the wood collected in coppices managed in very short, short, and average-rotation by farmers).
One also employs the expressions “ green fuel ” (according to the tendency to call “green” all that is conceived for less harming the environment) and “ vegetable fuel ” (which have the same operational limits as “agrocarburant” ).
There exist dies known as of “second generation” (die “cellulose ethanol” and die “oil of microalgue” in particular) which aim at better assessments energetics and increased productions.
Dies of first generation
The die oils
See also: Plant oil carburizing
Many plant species are oleiferous such as for example the Karanj, the pourghère ( Jatropha curcas ), the Palmier with oil, the Tournesol or the Colza. The outputs with the hectare vary from one species to another and are exceptional with the microalgues. Oils of worn cracklings, oils of slaughter-houses or fish shops can also be used.
Any plant oil extraction can be carried out by simple cold pressing - crushing, or by chemical way, or a combination of the two methods. The use of an organic solvent makes it possible to reach a level of extraction of 99% but at a higher cost. The Raw Plant oil (HVB, or HVP) can be used directly in the adapted diesel engines (in particular because of its relatively high viscosity). The triglycerides which constitute plant oils can also be transformed into monoesters methyl (Methyl Esters of Plant oil - EMHV) and into glycerol by a reaction of cross esterification with methanol molecules (one obtains ethyl esters with ethanol). The smaller molecules of the biodiesel thus obtained can then be used like fuel in the engines with lighting by compression. This biodiesel does not contain sulfur, is not toxic and is highly biodegradable. The Biodiesel is also called in France Diester ™.
The die alcohol
Many a species vegetable are cultivated for their sugar: it is the case for example of the Canne to sugar, the sugar Betterave, the Maïs, the Blé or lately of the Ulve.
the bio-éthanol is obtained by Fermentation Sucre S (simple sugars, hydrolized starch) by Levure S of the kind Saccharomyces . The ethanol can replace partially or completely the gasoline. A small proportion of ethanol can also be added in Gazole but this practice is not very frequent.
the Ethyl-thirdly-butyl-ether (ETBE) is a derivative (an ether) of ethanol. It is obtained by reaction between ethanol and the Isobutène and is used like additive with height of 15 % with the gasoline to replace lead. Isobutylene is obtained during the refining of oil.
the bio-butanol (or butanol) is obtained thanks to the anaerobic Gram bacterium positive Clostridium acetobutylicum which has enzymatic equipment enabling him to transform sugars into butanol-1 (acetonobutylic Fermentation). Dihydrogène, and other molecules are also produced: Acid acetic, Propionic acid, Acetone, Isopropanol and ethanol (see the diagram of the metabolic ways of '' Clostridium acetobutylicum ''). The companies BP and Dupont currently market the biobutanol; it has many advantages compared to ethanol and is more and more often evoked like biocarburant substitution for the hour of expensive oil. The production units of bioéthanol can be adapted to produce the biobutanol
the methanol (or " alcohol of bois"), obtained starting from methane is also usable, in replacement partial (under certain conditions) of the gasoline, like additive in the gas oil, or, in the long term, for certain types of combustible batteries. Methanol is however very toxic for the man.
The die gas
the bio- Méthane is the principal one constituting Biogaz resulting from the alkaline Fermentation (or Méthanisation) of animal or vegetable organic matters rich in sugars (starch, cellulose, with difficulty woody residues) by bacteria methanogenes which live in anaerobic mediums. The independent sources are the muds of the purification plants (the production makes the station at least partly autonomous in energy), the liquid manures of breedings, the effluents of agribusiness industries and household waste. The gases resulting from fermentation are composed of 65% of methane, 34% of CO2 and 1% of other gases whose hydrogen sulfide and diazotizes it. Methane is one biocarburant being able to replace the Natural gas (this last is composed of more than 95 % of methane). It can be used either in engines with positive ignition (technology petrol engines) or in engines known as dual-fuel. They are diesel engines supplied with majority by methane or biogas and for which the explosion is ensured by a light contribution of Biodiesel/oil or Gazole. When it is produced with small or average scale, methane is difficult to store. It must be thus to be exploited on the spot, in food of a Generator for example.
A possibility which is developed in Europe and in the United States east its purification to the standards of natural gas so that it can be injected in the networks of Natural gas, and thus to replace of small portion for the traditional uses which are made by it. The energetic efficiency of this die biocarburant is currently much better than the others and technically simpler but it is médiatisée very little in France.
dihydrogene (bio-hydrogen): the reforming of bio-methane makes it possible to produce dihydrogene. This last can also be produced by bacterial way or microalgale.
die BTL (or Biomass to liquid ) makes it possible to obtain fuels thanks to the Procédé Fischer-Tropsch.
the Gas-generating : invented by Georges Imbert (1884-1950), the gas generator is a system which can replace the gasoline in the spark-ignition engines by solid fuels, of which wood.
The die charcoal (biocarburant solid)
The Charcoal is obtained by Pyrolyse wood, straw or other organic matters. An Indian engineer developed a process allowing of Pyrolyse R the sugar cane sheets, sheets which are almost never developed currently.
Dies of second generation
A major disadvantage for the development of the fuels of first generation is that they enter in competition with the food cultures and the ecosystems to high biodiversity. New dies with purely energy vocation, the best outputs and more interesting on the emergent environmental level gradually, one then speaks about cellulose ethanol.
- the transformation of the Lignin and the Cellulose (of wood, the straw) into alcohol or gas (lignocellulosic-biocombustible die) been the subject of intense research in the whole world. Technologies of the transformation of the cellulose (the most common macromolecule on ground) are complex, energy of enzymatic degradation to the gasification. Canadian companies (such as for example Iogen), American (Broin Co.) and two Swedish universities (pilot Factory of Örnsköldsvik) currently pass to the phase of cellulose industrial production of ethanol.
- According to the director of the Program of the United Nations for the Environment, the Termites have bacteria able to transform " efficiently and economic chips of sugar wood for the production of éthanol". The enzymes found in the digestive tract of the termites and produced by these symbiotic bacteria are indeed able to convert wood sweetens some in 24 hours the potential of the cellulose die is enormous and technologies evolve/move quickly.
It is probably starting from cultures of Microalgue S, 30 to 100 times more effective than the terrestrial oilseeds, than of the biocarburants could be produced with the best outputs, making thus possible a mass production without massive deforestation nor competition with the food cultures. To obtain an optimal output oils some, the growth of the microalgues must be carried out with a concentration in CO2 from approximately 13%. This is possible at a very weak cost thanks to a coupling with a source of CO2, for example a thermo plant with coal, natural gas, biogas, or a unit of alcoholic fermentation, or a cement factory. The fermentation of sugars (coming directly from plants as the cane with sugar, of sugar beet, the hydrolysis of the starch of corn, corn, or of the hydrolysis of cellulose presents in wood as well as the stems and the sheets of all types of plants) out of ethanol generates great quantities of CO2 (with high concentration) which can nourish the microalgues. The production of 50 liters ethanol by alcoholic fermentation is accompanied by the production of 15 liters CO2. With regard to the die oils, the oil cakes obtained after extraction of plant oil ( Jatropha curcas , karanj, saijan, sunflower, colza etc) can be used to produce biogas (methane). Methane can feed a thermo plant (electrical production) and released CO2 can also nourish the microalgues. The assessment total carbon and the durable character of the die thus depend on the source of C02 used. The coupling cellulose die ethanol - die microalgue is a way with a future from the point of view of a sustainable development. To note that the growth of the microalgues is of course possible under the natural atmospheric conditions (concentration in CO2 of 380ppm), but the outputs are then much weaker.
Ulva lactuca , the lettuce of sea or Ulve is in this moment with the test in Denmark. To the University of Aarhus, Michael Bo Rasmussen already passed to the tests. The idea to use the coast appears interesting in this country.
the Whey or small-milk is on the way to become a source of biocarburants. The German dairy group Müllermilch announced that it would launch out, from here the end of the year, in the production of bio-éthanol starting from residues of milk, first world! This die has as an main advantage developing a by-product little used of the milk industry.
Jatropha curcas , a shrub which pushes in arid region and which produces on average 1892 liters of oil per hectare and per annum, is also a very promising plant. Its culture (realized in manner éco-person in charge) makes it possible in particular to fight against the turning into a desert (photographs opposite). At the time of the Biofuel Summit 2007 which was held in Madrid, the Dutch specialist Winfried Rijssenbeek (RR Energy) made the promotion of qualities of this euphorbiacée: " This plant, which produces oleaginous seeds, is an alternative interesting to the palm trees with oil and soya for the south. Initially because it is not edible and thus does not enter in competition with the food sector. Other favors, Jatropha curcas can be cultivated on difficult, unsuitable grounds the other cultures and makes it possible to fight against the turning into a desert ".
Pongamia pinnata (or Karanj) is a tree with rapid growth, nitrogen fixer, very resistant to the dryness, which push in full sun, on difficult grounds, even on salted grounds, and oil producer. India currently strongly encourages the plantation of this tree (as well as shrub Jatropha curcas ) in the unsuitable zones with the traditional cultures, this in optics to produce plant oil. The average outputs are of 5 tons graines/ha/an (1,7 tons of oil and 5,3 tons of cakes) it tenth year, which is excellent.
The Polyculture (association of several species) is preferable by far from an environmental point of view to monocultures. One can thus plan to plant forests where mix Mahua, Saijan, Karanj as well as other gasolines useful for the local populations.
The energy assessment thus the assessment carbon is in general better when one rather adapts the engine to pure plant oil (Moteur Elsbett for example) than to adapt plant oil (chemical conversion into Biodiesel, heavy process) to engines designed to function with derivatives of oil.
A team of the Université of Wisconsin, directed by James Dumesic exposed in June 2007 in the Nature a new process of transformation of the Amidon in order to produce a new liquid fuel, the Diméthylfurane. Its properties seem more advantageous than those of ethanol.
Economic assessment and interest geostrategic of the biocarburants
- Worldwide production of EMHV (biodiesel, " Diester") in 2005 ~ 4 million tons (Germany: 45% of the worldwide production - France: 15% - Italy: 11% - The USA: 7%)
- Worldwide production of ethanol in 2005: 36 million tons including 75% used for carburation (37% of the worldwide production: South America - 36%: North America and Central America - Asia: 15% - Europe: 10%)
- Worldwide consumption of oil in road transport in 2005: 1,6 billion tons
" In 2005, European production of ethanol " carburant" was of 750.000 tons for 950.000 tons consumed: 200.000 T were thus imported. First producer until 2001, France from now on is preceded by Spain, Sweden and Germany. With regard to die EMHV, the production increased in a very important way over the 5 last years (annual average growth rate: 35%). France produced 492.000 tons in 2005, of which a part at summer exported towards Germany. Germany is from now on the principal producer and European consumer of EMHV: 1,7 MT were produced in 2005 to compare with the 450.000 tons produced in 2002, that is to say a multiplication by almost 4. " - Source: IFP
The two larger bioéthanol producers are the the United States and the Brésil with 16 and 15,5 billion liters produced in 2005. European Union: 900 million liters (the principal producer is the Spain).
The various dies of biocarburants can stimulate the agricultural activity the synthesis of biocarburants to the local scales (Plant oil carburizing for example) allows an energy autonomy of the farmers, and to limit the transport of the fuels.
See also: Biocarburants in Brazil
See also: Biocarburants in the United States
See also: Biocarburants in the European Union
See also: Biocarburants in France
Compete with the food production
Vis-a-vis the climate changes and with the blaze of the oil prices, the biocarburants are considered like an element of durable energy alternative. But the agrobiocarburants (biocarburants produced starting from agricultural produce) could also support the deforestation and the erosion of the grounds, and compete with the food. Their production only guided by economic imperatives could lead to serious social consequences and/or environmental. The development of the production of the Palm oil for agribusiness industry and the organic chemistry being accompanied by a very fast destruction of forests in Malaysia, one could fear an aggravation of this situation if this culture ceased being minority in the production of biocarburant world. The price of twisted, basic food in Latin America, recently flamed in Mexico. The Mexican government made some carry the blame on exports of corn towards the USA where it is used to produce ethanol. On her personal site, Jean-Marc Jancovici, supports that the replacement of the totality of the oil consumed in the world by oil of colza, sunflower oil and beet alcohol is impossible, they can however be one of the means allowing a reduction in the recourse to fossil energies. Studies taking into account other agricultural cultures and other modes of production concluded with the possibility for the bioénergie of ensuring a significant share of our requirements in displacement. The requirements with this scenario are important measurements of energy efficiency and a passage towards a local agriculture not very consuming energy.
The use of part of the arable lands to produce biocarburants (die alcohol or die oils) can be a factor of rise in the prices of the basic agricultural produce intended for the food. The course of corn, used to produce ethanol, has reached in 2006 its more high level for 10 years with the purse of Chicago, because of an imbalance of supply and. That was reflected on the cost of living in Mexico and in other countries of Latin America where the cornstarch is one of the bases of the food, even if the rise in the prices of twisted Mexican remains mainly ascribable has a political decision (liberalization of the market of twisted before subjected at a fixed price by the state) and with the economic context (monopolistic position of the principal producer of twisted in Mexico).
This rise can be reflected on the price of other agricultural produce. The experts of the Deutsche Bank estimate that will be the case for the bovine meat (the cattle is nourished with corn). In Germany, where 16% of surfaces of cultures are currently intended for the production of biocarburants, the price of malt with doubled in 2006, involving a rise in the price of beer.
This assertion must however be placed in the context of the national plans of developments of the biocarburants: according to Claude Mandil, director of the international agency of energy, the current programs of biocarburants have objectives " agricultural and not énergétiques". Accordingly, the goal of the developed countries (the United States, Europe) is to subsidize their agricultural dies and to run out their production without having recourse to massive exports disputed more and more in the authorities controlling the international business. Within the European Union, the development of biocarburant occurs in fact parallel to the reduction even the suppression of obligatory freezing on the one hand ground cultivated, (or fallows) set up in 1992, whose objective was to fight against the agricultural suproduction. In addition, in the situation former of weak farm prices, the flow at low prices of products towards slightly structured countries had negative effects on the installation or the maintenance of a local prodution of these countries. The rise of the farm prices, can be felt hard by the consumers of the countries in the process of development, it is also a support in fact for their own producers.
The developing countries specialized in an agricultural monoculture (Brazil, Indonesia) developed economic mechanisms making it possible to guarantee itself of a fall of the price synonymous with economic crisis. The breeding remains the principal cereal consumer produced in the OECD countries (80 to 90% of the production), far in front of the industry of the biocarburants. The work undertaken on behalf of OECD and FAO and presented in the " report/ratio; Agricultural Outlook 2007 - 2016" confirm this analysis and charges the agricultural raising of prices to exceptional climatic events (drynesses), the weakness of existing stocks and a strong demand related to the changes of dietary habits in the world population (rise of the consumption of dairy products and meats). However, in the long run the impact of the structural modifications accompanying fast development by the biocarburants could maintain farm prices high in the next decade.
The biocarburants of second generation (microalgues, oleiferous plants of arid regions etc) to purely energy vocation should make it possible to solve this problem of competition with the cultures with food vocation.
In France, the French objective of 7% of biocarurants in 2010 represents 310.000 hectares of field crops, that is to say 1% of SAU, according to ONIGC. ADEME estimates for its part that the same objective would mobilize approximately 2 million hectare and that it would be necessary to manage the tensions between energy and food production consequently.
Impacts on the biodiversity, the resource water and the grounds
Production of biocarburant, request means of the intensive agricultural production, in term of manure and plant health products. In a study published in Bioscience , the researchers Marcelo Dias de Oliveira et al., (University of State of Washington) conclude that the die ethanol starting from cane with sugar reduces the biodiversity and increases the erosion of the ground.
The production of ethanol in Brazil, is based in particular on the exploitation of new grounds cleared for that.
Dukes estimates that the replacement of the fossil fuels by a combustion of current plants would correspond at least to 22% of the terrestrial vegetable production (including marine plants), thus increasing by 50% the appropriation of this resource by the man, and compromising the survival of the other species which depend on it.
Tyler Volk, professor of the Earth Systems Group of the department of biology of the university of New York, estimates that “ the massive production of ethanol could increase the pressure on the cultivable grounds, raise the prices of food and accelerate deforestation ”.
The durable character of the production of biocarburants can be put at evil if it is carried out in a nondurable way: exhaustion of the grounds, water pollution and destruction of natural environments for this production. According to the estimates of the the friends of the Earth , the plantation of palm trees with oil was responsible for 87% of the Déforestation in Malaysia between 1985 and 2000. 4 million hectares of forest was thus destroyed in Sumatra and Borneo. 6 million hectares in Malaysia and 16,5 million in Indonesia are programmed to disappear. The threat is serious. " Even the famous National park of Tanjung Puting in Kalimantan was put in part by growers. The orangs-outans in freedom are dedicated to disappear. The rhinoceroses of Sumatra, the tigers, let us gibbons them, the tapirs, the nasiques ones and of the thousands of other species could take the suite." . Several studies whose report/ratio of British Department for Transport on the biocarburants note the urgency to stop deforestation in tropical zone. This deforestation, related mainly or not to the biocarburants relates to in particular the Brésil (destruction of the Amazon forest to carry out monocultures of cane with sugar), the Malaysia, the Indonesia, the Kenya, the Congo, the Nigeria, the Liberia, the Brésil, the Colombia, or the Mexico.
Energy-savings and gas emission with greenhouse effect
The man emits each year 24 billion tons of C02 in the atmosphere. The massive emissions of Gaz to greenhouse effect (C 02, CH 4 etc) are at the origin of the Climate warming.
The combustion of fossil energies (Oil, coal, Natural gas) led to the release of CO2 in the atmosphere, carbon which was trapped in the basement since million years (from where the term of fossil energy). It comes from the decomposition of the fauna and the flora which lived on the Earth before. The consumption of these hydrocarbons releases in the atmosphere of CO2 which had left the Cycle of carbon since several million years.
On the contrary, the carbon emitted during the combustion of biocarburants (die oils or die ethanol) was fixed beforehand by the plants (colza, corn, corn…) at the time of the Photosynthesis. The assessment carbon thus seems, a priori, neutral and the recourse to this energy makes it possible to avoid additional gas emissions with greenhouse effect. To determine if there is a real profit in term of emission of CO2, it is a question of making the energy assessment of the production of biocarburant.
A study published in Nature resources research, the researchers David Pimentel and Tad Patzek conclude “that there is no energy benefit to use the biomass of the plants to manufacture fuel.” at the end of a calculation tending to show that total energy necessary to the production of ethanol starting from corn, with the production of wood and that of biodiesel starting from soya or sunflower is for each one of these cases higher from 27 to 118% with produced energy. It is given for that of the quantities of energy spent to manufacture and during conditioning, transport and spreading of the pesticides and the Engrais, with the manufacture of the agricultural tools, the drainage with the irrigation as well as the energy spent by the workers them-even apart from their work. This study nevertheless was denounced like strongly skewed by the assumptions taken and the interpretation of the results. The stations of energy expenditure are for example nonverifiable or are based on obsolete techniques.
In France, the Agency of the environment and control of energy (ADEME) and the Réseau Action Climate publish studies on the interest of the biocarburants to reduce the gas emissions to greenhouse effect.
The ADEME carried out a synthesis of the various studies, by standardizing the results. The conclusion of the summary report of 2006 is: " Whereas the results published are radically different and give place to opposed conclusions, the standardized results make it possible to draw a conclusion common to the three studies: the ethanol and the biodiesel allow both to reduce the dependence to nonrenewable energies compared to the fossil fuels. With regard to the GES, the indicators published underline the same benefit of the biocarburants compared to the fuels fossiles.". The effective valorization of the coproduits (by the cellulose die ethanol or methanisation for example) will make it possible to improve this assessment considerably. The conclusions of a report of the British Department for Transport go in the same direction, while however underlining the considerable environmental impact of the development of the traditional dies in tropical zone. These impacts can, according to ONG Via Campesina, to result in returning the biocarburants worse than oil than they replace.
However, a recent study of P.J. Crutzen and. Al (P.J. Crutzen, specialist in nitrogen oxides and the layer of ozone, received the Nobel Prize of chemistry for its work on these subjects) claims that the use of the biocarburants of first generation could in makes increase the greenhouse effect (see the article and its discussion on line on, to also see for a simple presentation of this article on the site of chemistryworld). According to these authors, the increase in the emissions of Protoxyde of nitrogen had with the use of nitrate fertilizers for the production of biocarburants could have a more unfavourable effect on the greenhouse effect than the reduction of the production of CO2. Indeed, because of the persistence of the nitrogen protoxide in the atmosphere, this gas has, over one one hundred years duration, a capacity heating equal to 296 times that of CO2. According to Crutzen, the nitrogen protoxide emissions would have been underestimated until now. The arguments for and against this thesis are available in the two preceding references.
According to the Network Action Climate, in a study published in May 2006, the results of the die ethanol present energy-savings limited, very relative for ETBE, even negative for corn ethanol, and allow some savings in GES.
Always according to the same study, the oleaginous die is much more interesting especially with regard to pure oil. The energy assessment as well as the assessment carbon are always much better when one rather adapts the engine to pure plant oil (Moteur Elsbett for example) than to adapt plant oil (chemical conversion into biodiesel, heavy process) to engines designed to function with derivatives of oil. To stronger reason if one prefers perennial plants located zones where they do not enter in competition with others. Plants which can develop in arid region like Jatropha curcas, Pongamia pinnata or Madhuca longifolia could present much better results.
The utility of the biocarburants depends thus in an important way and the die chosen, and the effective valorization of the coproduits. From where importance to find outlets to them, in particular for the oil cakes of colza and sunflower.
In France, according to the ministry for industry, two principal biocarburants is used at present: the ETBE (ethyl thirdly butyl ether, starting from ethanol) for the vehicles gasoline (90% of the consumption of biocarburant in France) and the EMHV (biodiesel or Diester) for the vehicles diesel. Dimensioned ethanol the ETBE receives the preference of the ministry compared to E85, richer (85%) in ethanol: With the technical plan, the ETBE is the best way of incorporating ethanol in the fuel, thanks to its octane number raised as much as with its low volatility. This technical conclusion is the subject of a consensus in professional environments. What leads the Network Action Climate to say: the ambitious and expensive governmental play which lays down to replace 7% of the oil fuels by agrocarburants from here 2010 would decrease the emissions of GES of road transport by less than 7% (whereas road transport in France saw their emissions GES to increase by +23% since 1990). .
On a world level, the production of biocarburants in 2005 was of 37 million tons (MT) for bioéthanol and 3,2 MT for the biodiesel.
According to Total Canopy Programs, gathering the scientific leaders on the tropical subject of the forest, deforestation is one of principal the person in charge of emmissions of gas with greenhouse effect. With 25% of emmissions total it is preceded only by energy, but well with the top of transport (14%).
Several recent articles denounce in the biocarburants a mirage which would make us lose sight of the fact essence: to stop deforestation and to decrease fuel consumption. The danger is that the production of biocarburants accompanies a consumption increasing by fuel, being restricted to facilitate the provisioning of it.
Biocarburants and quality of the air
The combustion of the bioéthanol produces more Aldéhydes that the gasoline, but those of bioéthanol are less toxic (Acétaldéhyde S against Formaldéhyde S for the gasoline). According to Jacobson Mark of the university of Stanford, the combustion of ethanol involves the formation of oxides of nitrogen and volatile organic compounds (COV), which them react to form ozone, person in charge of the formation of the Smog. " An even modest rise of ozone in the atmosphere can be at the origin of an increase in the cases of asthma, of a weakening of the immune system. According to the World Health Organization, more than 800.000 people die annually in the world because of ozone and pollution atmosphérique." - “With final, the incidence of cancers related to E85 would be similar to those related to the gasoline. In addition, in certain areas of the country, the use of E85 would result in to increase ozone the concentration, a perfect ingredient of the fog”.
Possibility of replacement of fossil energies
In 2003, the biologist Jeffrey Dukes calculated that the fossil energies burned in one year (1997) came from a prehistoric organic matter mass which represented more than 400 times the energy which contrary is fixed and accumulates naturally in same time on planet. In the same article, Dukes estimates that the replacement of the fossil fuels by a combustion of current plants would correspond at least to 22% of the terrestrial vegetable production (including marine plants), thus increasing by 50% the appropriation of this resource by the man.
Obtaining these biocarburants requires important cultivable surfaces. According to Jean Marc Jancovici, Consulting engineer specialist in the emissions of gases with greenhouse effect, it would be necessary for example to cultivate 118% of the entire surface of France in sunflower to replace the entirety of the oil 50Mtep consumed each year by French in transport (104% of national surface with Colza, 120% with beet and 2700% with corn). To replace completely fuel consumption fossils by biocarburants, it would take… several times terrestrial surface. The biocarburants will be only one supplement as long as we do not pass to the era biocarburants of second generation. For Jean-Marc Jancovici, the biocarburants are thus an interesting problem of agricultural policy, but a negligible element of an energy policy .
The European directive 2003/30/CE request so that in 2010 the biocarburants account for 5,75% of consumption. France envisages to assemble this rate to 10%. The British government hopes that the biocarburants can provide in 2050 a third of the demand for carburizing, which one envisages the increase.
History and prospects
The biocarburants parallel to appeared the birth auto industry; Nikolaus Otto, inventor of the Engine spark-ignition , had conceived this one to function with ethanol. The Ford T (produced of 1903 to 1926) rolled with this alcohol. Diesel Rudolf, inventor of the combustion engine made turn its machines to the Groundnut oil. At the time of the two world wars, the Gazogène S quickly appeared to avoid the lack of fuel or gasoline.
In the middle of the 20th century, when oil became abundant and cheap, the industrialists and the consumers ignored the biocarburants. The first and second Oil crisis (1973 and 1979) made them again gravitational. Many studies were thus led at the end of the years 1970 and to the beginning of the year 1980. In the United States, work of the NREL ( National Renewable Energy Laboratory , US Department off Energy , DOE) on renewable energies started in the years 1970 in the context of the Peak American oil, which had been envisaged besides since 1956 by the geophysicist King Hubert. It then appeared essential to the US government to turn to foreign oil sources or to develop other fuels.
The oil counterblow of 1986 (prices of the Pétrole drop), and the lobbying of the oil Multinationale S made fall enthusiasm for the agrocarburants. Since 2000, a rise of the oil price, the approach of the oil Peak, the need for fighting against the Greenhouse effect and finally the threats on the security of supply led the governments to multiply the speeches and the promises of assistances for the sector of the agrocarburants. George Bush in her speech of the union of January 2006, declared that the objective of the USA east to reduce by 75% the oil importations coming from the the Middle East since 2025. The European commission wishes that the Member States include at least 5,75% of biocarburants in the gasoline, by subsidizing the biocarburants. Finally the Sweden aims at an energy independence since 2020.
In April 2007, a report/ratio of UNO does not manage to quantify the advantages and disadvantages of the biocarburants. He proposes to the decision makers to encourage their production and durable use as well as others bioénergies , while seeking to maximize the benefit for the poor and the environment while developing the Research and development for uses of public interest. Two projects of European directive are under examination in 2007; on the quality of the biocarburants and their promotion.
En 2007, the requests for subsidy in Europe related to 2,84 million ha, whereas the device of assistance of the CAP was planned (in 2004) for 2 million ha devoted to the agrocarburants. Only 70% of the ha could thus be subsidized (45€ per ha). (whereas one cultivated of them already 1,23 million ha. This subsidy could be called in question Pa the police chief European to agriculture Mariann Fischer Boel in a Communication " Checkup of the CAP " , the oil price (90 dollars the barrel) does not justify any more this help. The last écobilan makes in France was made by PWC (consulting) in 2002. Following the Grenelle of the Environment (Oct. 2007), in France the government ordered new with the Ademe.
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