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Asunto:[LEA-Venezuela] Biocombustibles: ¿opción viable? - Biofuels: An ad visable strategy?
Fecha:Martes, 13 de Marzo, 2007  17:40:35 (-0400)
Autor:Jorge Hinestroza <jlhinestroza @.....com>

 
----- Mensaje original -----
Para: Alert
Enviado: Martes, 13 de Marzo de 2007 05:03 p.m.
Asunto: [AlertOilwatch] Biocombustibles: ¿opción viable? - Biofuels: An advisable strategy?


English Below

http://news.bbc.co.uk/hi/spanish/science/newsid_6430000/6430453.stm

BBC NEWS
Jueves, 8 de marzo de 2007 - 17:55 GMT

Biocombustibles: ¿opción viable?

Los biocombustibles, en lugar de solucionar el cambio climático, podrían terminar dañando más al medio ambiente.

Esa es la conclusión de una investigación realizada por investigadores españoles.

Muchos, en la política y la ciencia, ven a los biocombustibles como una fuente limpia y renovable de energía y una alternativa para reducir la emisión de gases contaminantes y el deterioro del medio ambiente.

Sin embargo, un nuevo estudio del Instituto de Ciencia y Tecnología del Medio Ambiente de la Universidad de Barcelona afirma que el uso de biocombustibles conlleva un impacto negativo tanto económico, social, como medioambiental.

Producción

Los biocombustibles, como el biodiesel y el etanol, se derivan de productos orgánicos como el maíz, caña de azúcar, aceites vegetales o estiércol de vaca.

"El principal argumento a favor de los biocombustibles es que ayudarán a reducir la concentración de gases de efecto invernadero en la atmósfera" dijo a BBC Ciencia Daniela Russi, quien llevó a cabo la investigación.

Sin embargo tal como señala Daniela Russi, "un análisis más detallado del ciclo de vida del biodiesel revela que el ahorro de energía y de CO2 no es tan alto como se piensa, e incluso podría ser negativo".

La materia prima que se usa en la producción de biocombustibles se obtiene mediante agricultura intensiva.

"Este sistema implica un alto uso de fertilizantes, pesticidas y maquinaria, ya que con métodos agrícolas menos intensivos, la producción sería mucho menor y los requerimientos de tierra y costos serían mucho más altos", afirma Russi.

"Este proceso requiere además del uso de combustibles fósiles (carbón y petróleo) tanto durante las fases de producción como en el transporte desde y hacia las plantas de procesamiento".

Contaminación

Otro argumento que a menudo escuchamos a favor de los biocombustibles es la contaminación urbana.

Estos combustibles no sólo se ven como una opción "verde" global y local para reducir la contaminación del tráfico y todos los problemas de salud asociados a ésta.

"En realidad -dice Daniela Russi- las ventajas en este aspecto son muy modestas".

Según la investigadora si se sustituyera la gasolina diesel con una mezcla de 5.75% de biodiesel -tal como intenta establecer la Unión Europea- los óxidos de nitrógeno (NOx) aumentarían de forma insignificante y los hidrocarburos (HC) y el monóxido de carbono (CO) disminuirían respectivamente 6% y 3%.

"Frente a estas modestas ventajas, las desventajas de la producción a gran escala de biodiesel, son enormes".

Estas desventajas, dice, incluyen los enormes requerimientos de tierra para cultivar, la sustitución de cosechas alimenticias por monocultivos, la deforestación para cultivos energéticos.

Esto a su vez conduciría a la desaparición de la biodiversidad, la disminución de tierras fértiles y agua y los efectos sociales negativos como el desplazamiento de comunidades locales.

Costo del maíz

Otra posible consecuencia, afirman los investigadores, es la reducción en la disponibilidad de alimentos.

Un ejemplo reciente se vio con el precio del maíz en Estados Unidos que aumentó a su valor más alto en 10 años debido a la creciente demanda en ese país de bioetanol derivado de maíz.

México -principal importador de maíz de Estados Unidos- resultó especialmente afectado ya que la gente debió pagar hasta 30% más por uno de sus alimentos básicos: la tortilla de maíz.

"En conclusión -dice Daniela Russi- el biodiesel no contribuirá a la solución de los problemas derivados de nuestra dependencia en los combustibles fósiles".

"Incluso -agrega- ésa es una idea que puede ser hasta peligrosa".

"Porque podría fomentar un falso optimismo de que hay una solución tecnológica para resolver el problema de nuestra excesiva dependencia a los combustibles fósiles".

"Y la única forma posible de lograrlo es modificar nuestros patrones de consumo con medidas de ahorro energético y de diversificación de fuentes de energía".


ENGLISH
Biofuels: An advisable strategy?

Biofuels have been an increasingly hot topic on the discussion table in
the last few years. In 2003 the European Union introduced a Directive
suggesting that Member states should increase the share of biofuels in
the energy used for transport to 2% by 2005 and 5.75% by 2010. In 2005
the target was not reached and it will probably not be reached in 2010
either (we are in 2006 at approximately 0.8%), but anyway the Directive
showed the great interest that the European Commission places on
biofuels as a way to solve many problems at once. The new European
energy strategy, presented on 10th January 2007, establishes that
biofuels should represent at least 10% of the energy used for transport .

Biofuels are not competitive with fossil fuel-derived products if left
to the market. In order to make their price similar to those of petrol
and diesel, they need to be subsidized. In Europe, biofuels are
subsidized in three ways:

1) agricultural subsidies, mainly granted within the framework of the Common Agricultural Policy;
2) total or partial de-taxation, which is indispensable, because energy taxes
account for approximately half of the final price of petrol and diesel;
3) biofuels obligations, which establish that the fuels sold at the pump
must contain a given percentage of biofuels.

These three political measures need financial means, which are paid for
by the European Commission (agricultural subsidies), by the governments
(reduced energy revenues), and by car drivers (increase in the final
fuel price). For this reason, an integrated analysis is needed in order
to discuss whether investing public resources in biofuels and employing
a large extension of agricultural land is the most advisable strategy to
solve the problems associated with fossil fuels.

The main argument behind the policies in favour of biofuels is based on
the idea that biofuels would not increase the concentration of
greenhouse gases in the atmosphere. In fact, the amount of carbon
dioxide emitted by biodiesel in the combustion phase is the same as that
absorbed by the plant during its growth through photosynthesis,
resulting in a neutral carbon budget. Moreover, substituting part of the
oil products with biofuels would reduce the European energy dependency
and increase energy security.

However, a more careful analysis of the life cycle of biodiesel reveals
that the energy (and CO2) savings is not so high as it might seem at
first sight, and in some cases might even be negative. In fact, the raw
materials for biofuels are normally obtained with intensive agriculture,
which imply a high use of fertilizers, pesticides and machinery. The
reason is that, with less intensive agricultural methods, the yield
would be lower and the land requirement and the costs would be higher.
Also, fossil fuels are used in the processing phase (oil pressing,
trans-esterification) and for transporting the oil seeds to the
processing plant and from there to the final users.

In any case, even if the objective of the Directive were met, the
savings would not be significant. In fact, since the transport sector
accounts for 30% of the final energy consumption, the 5.75% of the fuels
for transport corresponds to 1.8% of the final consumption. Taking into
account that this amount requires the indirect use of fossil fuels, the
final savings would be even lower.

For example, considering a very optimistic output/input ratio (the
biodiesel produced using one unit of fossil fuels) of 2.5 , we obtain
that reaching the 5.75% percentage (approximately 20 million tons of oil
equivalent) would imply saving around 36 million tons of CO2 equivalent,
i.e., less than 1% of the European Union emissions in 2004 (4,228
million tons CO2) If we take into account the emissions related to the
transport of raw materials that are imported and the imports of food
crops that would be substituted by energy farming, the savings would be
even less, and if the oil seeds are imported from outside Europe
possibly even negative.

Another point that is often raised to promote biofuels is urban
pollution. Biofuels are not only seen as a "green" fuel on a global
scale (reduction of greenhouse effect) but also on a local scale. They
would contribute to reducing traffic contamination, and therefore the
numerous ailments associated with it. In reality, the advantages from
this point of view are very modest. For example, according to a study of
the USA Environmental Protection Agency (2002), if diesel is replaced
with a blend of 20% biodiesel (B20), Nitrogen Oxides (NOx) would
increase by 2%, particulate matter (PM), unburnt Hydrocarbons (HC) and
Carbon Monoxide (CO) would decrease by respectively 10.1%, 21.1% and 11%
. Therefore, it can be assumed that with a 5.75% blend, the reduction in
PM, HC and CO would be respectively 3%, 6% and 3% (and the increase in
NOx would be negligible).

Against the modest advantages (a small substitution of fossil fuels and
a slight reduction of some contaminants with respect to diesel), the
disadvantages of a large-scale biodiesel production are apparent.
Due to the low yield, the land requirement is enormous. In the Biomass
Action Plan (Annex 11) it is calculated that in order to achieve the
5.75% target (18.6 million toe biofuels), about 17 million hectares
would be needed, i.e. one fifth of the European tillable land (97
million hectares). Since there is not so much marginal and abandoned
land in Europe, the consequence would be the substitution of food crops
and a huge increase of the food imports.

For this reason, both in the Biomass Action Plan and in the EU Strategy
for Biofuels it is stressed that Europe will promote the production of
raw material for biofuels in extra-European countries, where the
European Commission intends to incentive energy farming.
This means that the impacts of energy farming would be exported to
Southern countries. It is easily foreseeable that if the European demand
for biofuels increased because of biofuel obligations and other
supporting policies, Southern countries may be stimulated to replace if
not food crops at least native forests with large monocultures.
Energy farming would presumably have a big role in deforestation,
because pristine forests would be cut down in order to cultivate energy
crops. The consequences would be, besides a worrying reduction of wild
biodiversity, a decrease in soil fertility, water availability and
quality, and an increase in the use of pesticides and fertilizers, as
well as negative social effects like potential dislocation of local
communities.

The European Directive, and in general all biodiesel promoting policies,
do not only imply a competition for arable land but might also incentive
plantations of palm trees, whose oil is cheaper than any other source.
Palm plantations are responsible for most deforestation in South Eastern
Asia and represent a real threat to the remaining native forests. Also
they are responsible for a high soil erosion rate. For example, between
1985 and 2000 in Malaysia palm plantations caused 87% of the total
deforestation and further 6 million hectares will be deforested to make
room for palm trees . The same more or less applies to sugarcane
plantations in Brazil.

Moreover, taking into account the CO2 emissions due to inter-continental
transport and the increase of CO2 in the atmosphere due to deforestation
(forests are CO2 sinks), the final result might be an overall increase
of the greenhouse emissions instead of the whished reduction.
Another possible negative consequence is a reduction in world food
availability, which can be a particularly serious problem in a context
of increasing population and energy demand. A recent example is the
increase in corn price in Mexico by 30% in early 2007, caused by the
growing demand for corn-derived bioethanol in the USA (Mexico is a net
importer of corn from the USA). Some use the term "ethanolinflation" .

Also, a large scale biodiesel production would imply a strong
environmental impact in the agricultural phase: the huge monocultures of
energy crops would dramatically reduce agricultural biodiversity, with
strong environmental impact in terms of soil erosion, use of fertilizers
and pesticides, and water requirement. Also, one of the consequences may
be an increase in the use of GMOs. In fact, soybean, maize and rapeseed
(among the most used raw material to produce biofuels) are respectively
the first, second and fourth most important GMO crops.

Another argument often used in favour of biofuels is rural development.
However, it can be argued that support to biofuels should not be used as
agricultural subsidies. If the objective is to support agricultural
sector, subsidies should be granted to organic agriculture and landscape
protection.

Concluding, using public funding to support a large scale biofuel
production is not an advisable strategy. Obviously, these considerations
do not apply to used oil or agricultural residue recycling, nor
small-scale niche productions, all of which may be good strategies,
instead.

Summing up, biodiesel cannot contribute to the solution of the problems
related to the high dependency of our economy on fossil fuels. The idea
that biodiesel could be a solution for the energy crisis is not only
false, but also dangerous. In fact, it might favour an attitude of
technological optimism and faith in a technological fix of the energy
problem. We should never forget that if we want to reduce the use of
fossil fuels there is no magic wand: the only possible solution is to
modify consumption patterns.


Public release date: 7-Mar-2007

 Contact: Daniela Russi
 Daniela.Russi@uab.cat
 34-935-812-974
 ICTA, Universitat Autonoma de Barcelona


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