Biofuels

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Biofuels: a world issue.

TABLE OF CONTENTS

INTRODUCTION 3
THE FAVOURABLE CONTEXT TO THE EMERGENCE OF NEW FUELS 3
ORIGIN AND RESOURCES OF BIOFUELS 4
A) BIOMASS 4
B) SEVERAL TYPES OF BIOFUELS 4
BIOFUELS IN THE WORLD 6
A) ETHANOL 6
B) THE EMHV 6
ASSESSMENTS OF THESE FIELDS IN FRANCE 7
A) ECONOMIC ASSESSMENT 7
B) ECOLOGICAL ASSESSMENT 8
CONCLUSION 9
BIBLIOGRAPHY 10INTRODUCTION

Biofuels are perceived in many countries, like one of the means of fighting against the climatic change, but also like a realistic solution to the problem of dependence on oil resources.
In Europe, ambitious objectives of incorporation have been implemented (5,75 % in 2010 and 8% in 2015) to encourage the Member States to develop these fields significantly.
Nowadays, the transport sectorand the environmental changes lead many countries to develop several kinds of biofuels. Theses different fuels are manufactured from biomass which is contained in many resources: vegetal, vegetal waste, algae, fats… For example in France, biofuels are economic and ecologic facts.
However, many questions are increasingly raised about the roles of biofuels in international issues like:
- carbonemissions levels
- the “food and fuel” debate
- deforestation and soil erosion
- impact and water resources…

The favourable context to the emergence of new fuels

Several reasons explain the development of biofuel research
• The rising oil prices (mainly caused by instability in the Middle East),
• The concerns about a potential peak of oil prices
• The greenhouse gas emissions(causing global warming and climate change)
• The rural development interests

Indeed, the exhaustion of the oil reserves that has increased since a score of years leads governments to set up policies supporting alternative energy resources. And biofuels seem to be the only “renewable” alternative to oil fuels, especially in the transport sector, where biofuels can be mixed with gasoline or diesel.Furthermore, the use of biofuels in equal volumes with gasoline or diesel may reduce the greenhouse gas emissions by at least 60 to 70%.

Origin and Resources of Biofuels

Biofuel is a solid, liquid or gas fuel derived from a biomass.

a) Biomass

The biomass indicates the whole of the living matter. It is the product of the photosynthesis of carbon dioxide and water, carried out bycollection of solar energy by plants:
CO2 + H2O + solar energy = component hydrocarbon
(The fossilization of these hydrocarbon components gives oil, gas and coal).
The annual production of the biomass is estimated at 172 billion tons of matter, that is to say the equivalent in primary energy of 15 times consumed fossil energy. The interest of using the fine biomass isthat its capture and its use do not affect the climate.

Today in the world, we estimate that 5% of the total production of the biomass could be used for energy production. Consequently fuel production rate could increase from 11% to 30%. However, biofuels will probably never replace the whole of the oil products used in transport.

b) Several types of biofuels

A biofuel is a fuel producedfrom renewable organic materials, which mainly comes from raw vegetable materials. Then, a biofuel is different from the fossil fuels like petroleum and coal.
There are different types of biofuel depending on the techniques of production: oil, alcohol produced by alcoholic fermentation of hydrolyzed starch or sugar, gas fuels obtained from vegetable or animal biomass, or solid fuels like charcoal.The first generation of biofuels can be divided into three great families:

- biodiesel: it is the most common biofuel in Europe. It is manufactured from plants containing oil (colza, sunflower, soya, palm) or animal fats.
It is usually mixed with the gasoline by chemical conversion. We make vegetable oil react with methanol to obtain an EMHV (methyl vegetable oil esters). The...
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