JUST A BRIEF INTRODUCTION
Dear Blog readers i would like to introduce my personal section of the green blob giving a little definition of what we could considerer as a Bio fuel.
We could essentially define it as a fuel extracted by natural materials, in specific by what has been cultivate, and this is the main feature that allows it to be inserted into the main family of bio energy or renewable energies. But bio fuels maintain a little but significant difference with other sustainable energies. Windpower and solar energy are infinite sources of power but bio fuels are renewable as long as they are generated by crops. Their logic use should be the substitution of common and well known fuel like gasoline, with a positive impact over natural environment due to the lowest gas carbon emission. This characteristic is not the only favourable one to a big implementation and distribution of this kind of fuels, they could also play a big role in a future strategic power balance in the world of tomorrow. They will assure a complete independence from oil producer states.
Bio fuels are not a recent discover, if we look to the first diesel motor, lunched at the end of 19th century, we could see that it has been alimented by vegetable oil. Probably the evolution and the pressure of the market, with the new rampaging oil industry, has pushed the entire world into a non bio development. But now days this model shows us its limits if we look at the world pollution and also the strategic development with the incoming end of oilfields.This new category of fuel might be a solution for a substainable world but within their advantages bio fuels keeps also disadvantages. If we considerer an extensive use of them, they will produce a new run for free earth fields, to be used to crop of each vegetable is able to produce bio fuel, like the colonialism expansion of the 17th and 18th century. Deforestation and also starvation due to the lack of food, especially in Africa and other parts of the world will be dramatically often.
In this blog section I will try to put under the sunlight this debate especially looking at this early mentioned problems that are hidden into what we too much simply define as ecofriendly fuels.
WORLD ENERGY SITUATION
As first topic I will try to delineate the actual world energy situation with paying specific attention over classic energy resources. Oil, for example is seen like the covert engine of our economies and in a wide perspective of our lifestyle system too. Since the discovering of fire from our ancients in the prehistoric age, human been has confronted with an inexorable struggle and run to the procuring of energy. After the industrial revolution there has been a real explosion in energy demand towards our actual mass society. Our production system is based on oil natural gas and coal, and for the first one not only if we see it from an energy request perspective to move cars or industries but also through is derivates that are the core of our developed world, from cosmetics to clothes never forgetting all the plastic things that range from computers to chairs and so on. After second world war this particular common sense to intend evolution has been spread to each continent with the consequence of a growing oil and energy demand. Probably this way of seeing the evolution has been dictated by technical reasons but also political ones, during the cold war era two vision of the world were in competition and each side had to win earth and minds of people to assure the final victory. Industrial expansion, services and affluent society, seen as continuous progression on human evolution, had to bee guarantied at any cost, also if it would have meant disparity of natural resources, distributions of benefits and environment damage. Clime has changed during the last 300 years, from 1980 to 2010 world crude oil consumption has rose from 54 billions barrels per day until reaching about 90 billions.[1] Natural gas from 48,000 until over 110,000 billion cubic feet and coal consumption has well over doubled during the same period.[2] In general we can see that world total primary energy consumption has doubled during the last 30 years.[3] Power ambitions of new States like China , Brazil , India
[1] http://www.indexmundi.com/energy.aspx?product=oil&graph=consumption
[2]http://www.indexmundi.com/energy.aspx?product=gas&graph=consumption http://www.indexmundi.com/energy.aspx?product=coal&graph=consumption
[3] http://www.indexmundi.com/energy.aspx?product=total-primary-energy&graph=consumption
THE SOLUTION
With a steadily increase of oil price, the risk of an ending of oil fields and the first studies on greenhouse gases effects, since the second half of the 20th century academic studies and governments have focused on alternative fuels. They discovered again biofuels. Biofuels are the best way of reducing the emission of the greenhouse gases. Today, the use of bio fuels has expanded throughout the globe, expecially bio fuels derived from crops. Some of the major producers and users of biogases are Asia, Europe and America. Theoretically, biofuel can be easily produced through any carbon source; making the photosynthetic plants the most commonly used material for production. Almost all types of materials derived from the plants are used for manufacturing biogas. One of the greatest problems that is being faced by the researchers in the field is how to covert the biomass energy into the liquid fuel. The most important feature of biomass is that they are renewable sources of energy unlike other natural resources like coal, petroleum and even nuclear fuel. Some of the agricultural products that are specially grown for the production of biofuels are switch grass, soybeans and corn in United States. Brazil produces sugar cane, Europe produces sugar beet and wheat while, China produces cassava and sorghum, south-east Asia produces miscanthus and palm oil while India produces jatropha.
The first generation of biofuels
The first generation biofuels refer to the fuels that have been derived from starch, sugar, animal fats and vegetable oil. Some of the most popular types of first generation biofuels are:
Biodiesel: The most common bio fuel used in Europe. Biodiesel is typically made by chemically reacting lipids (e.g., vegetable oil, animal) with an alcohol. Bio Diesel is ready to be used in standard diesel engines.
Vegetable oil: These kinds of oil are the most useful becouse they can be either used for cooking or fuel. The oil is obtained using the conventional techniques of production.
Biogas: It is the gas produced with the biodegradation of waste materials which are fed into anaerobic digesters which yields biogas.
Bioalcohols: These are alcohols produced through the process of fermentation of starches and sugar. Ethanol is the most common type of bioalcohol whereas butanol and propanol are some of the lesser known ones.
All the informations have been taken from:
http://biofuel.org.uk
http://energyfromwasteandwood.weebly.com
https://najjapak.wordpress.com/category/first-generation-biofuels/
HIDDEN TRUTHS
Bio energy from renewable sources has its merits and is key to tackle global climate change. But Bio fuels are not as ‘green’ as they seem. To produce them, a large amount of land is need to cultivate the crop, together with irrigation, use of fertilizers, transportation, conversion and refinery processes, all these require an energy input with a parallel output of pollution.
It is increasingly understood that 1st-generation bio fuels produced primarily from food crops are limited in their ability to achieve targets for oil-product substitution, climate change mitigation and economic growth. Their sustainable production is under review, as is the possibility of creating undue competition for land and water used for food. A possible exception that appears to meet many of the acceptable criteria is ethanol produced from sugar cane.
In particular some negative characteristic are linked to these fuels… They:
· contribute to higher food prices due to competition with food crops
Last year in the U.S.
· are an expensive option for energy security taking into account total production costs excluding government grants and subsidies;
· provide only limited Green House Gases reduction benefits
An Oxfam briefing paper concluded that by 2020, the EU’s renewable fuel mandates could induce 46 to 68 times more emissions from deforestation in Indonesia
· do not meet their claimed environmental benefits because the biomass feedstock may not always be produced sustainably;
· are accelerating deforestation
Scientists and economists have been in agreement about the threat that fuel crops pose to not only global food prices, but also deforestation rates in the tropics. Gibb’s findings are based on a systematic analysis of detailed satellite images collected between 1980 and 2000, which shows that cropland converted to soybean cultivation in Brazil has grown at an average rate of 15% per year since 1990, and that oil palm plantations in Indonesia
· potentially have a negative impact on biodiversity; and
· compete for scarce water resources in some regions.
All the informations have been taken from:
http://www.birdlife.org/climate_change/biofuels/eu_biofuels.html
http://energyfromwasteandwood.weebly.com/generations-of-biofuels.html
http://thinkprogress.org/climate/2009/02/19/203712/do-first-generation-biofuels-spell-doom-for-tropical-rainforests-global-climate-worlds-poor/?mobile=nc
SECOND GENERATION BIO FUELS
The goal of second generation bio fuel processes is to extend the amount of bio fuel that can be produced sustainably by using biomass consisting of the residual non-food parts of current crops, such as stems, leaves and husks that are left behind once the food crop has been extracted, as well as industry waste such as woodchips, skins and pulp from fruit pressing.
First generation bio fuel processes are useful but limited in most cases: there is a threshold above which they cannot produce enough bio fuel without threatening food supplies and biodiversity. Many first generation bio fuels depend on subsidies and are not cost competitive with existing fossil fuels such as oil, and some of them produce only limited greenhouse gas emissions savings. When taking emissions from production and transport into account life cycle assessments from first generation bio fuels frequently approach those of traditional fossil fuels.
Given the current investments being made to gain improvements in technology, some expectations have arisen that, in the near future, these “new” bio fuels will reach full commercialization. This would allow much greater volumes to be produced at the same time as avoiding many of the drawbacks of 1st-generation bio fuels. However, from an IEA analysis, it is expected that, at least in the near to medium-term, the bio fuel industry will grow only at a steady rate and encompass both 1st- and 2nd-generation technologies that meet agreed environmental, sustainability and economic policy goals. The transition to an integrated 1st- and 2nd generation bio fuel landscape is therefore most likely to encompass the next one to two decades, as the infrastructure and experiences gained from deploying and using 1st-generation bio fuels is transferred to support and guide 2nd-generation bio fuel development.
But what are the main techniques involved in 2 generation Bio Fuels??...
Thermo chemical routes
Carbon-based materials can be heated at high temperatures in the absence (pyrolysis) or presence of oxygen, air and/or steam (gasification).These thermo-chemical processes both yield a combustible gas and a solid char. The gas can be fermented or chemically synthesized into a range of fuels, including ethanol, synthetic diesel or jet fuel.
Gasification
Gasification technologies are well established for conventional feedstocks such as coal and crude oil. Second generation gasification technologies include gasification of forest and agricultural residues, waste wood, energy crops and black liquor. Output is normally syngas for further synthesis. Syngas can also be used in heat production and for generation of mechanical and electrical power via gas motors.
Pyrolysis
Pyrolysis is a well established technique for decomposition of organic material at elevated temperatures in the absence of oxigen. In second generation bio fuels applications forest and agricultural residues, wood waste and energy crops can be used as feedstock to produce bio-oil for fuel oil applications.
Municipal Solid Waste: Municipal Solid Waste comprises a very large range of materials, and total waste arising are increasing.
Green Waste: Green waste such as forest residues or garden or park waste.
Black Liquor: Black liquor, the spent cooking liquor from the kraft process that contains concentrated lignin and hemi-cellulose.
Energy Crops: Plants are made from lignin, hemi cellulose and cellulose; second generation technology uses one, two or all of these components.
..and a little news..
http://www.guardian.co.uk/environment/2008/dec/30/biofuel-test-plane
http://www.bioenergywiki.net/Second-generation_biofuels
http://en.wikipedia.org/wiki/Second_generation_biofuels
http://www.connect-green.com/page/12/
http://www.greenfudge.org/2010/09/21/biofuel-from-garbage/
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