A

SEMINAR REPORT

ON

Recent developments in Biofuels

Submitted By: Guided By:

Mythilypriya S Kanan Parag Saxena

13BCH164 Asst. Professor

CHEMICAL ENGINEERING DEPARTMENT

INSTITUTE OF TECHNOLOGY
NIRMA UNIVERSITY
CERTIFICATE
1
This is to certify that Ms. Mythilypriya S Kanan 13BCH164 student of Chemical
Engineering, Semester V, of Nirma University, has satisfactorily completed the
seminar on Recent developments in Biofuels as a partial fulfillment towards the
degree of B. Tech. in Chemical Engineering.

Date:

Place:

Parag Saxena Dr. S.S Patel

Assistant Professor H.O.D

2
 Acknowledgement
I would like to express our gratitude to Dr. Sanjay Patel (Head of CH Department,
IT. NIRMA UNIVERSITY, AHMEDABAD) for providing me this opportunity to
do seminar on ― Advancements in biofuels.

I am very thankful to Assistant Professor. Parag saxena for his help. I express my
deepest gratitude for helping and guiding me at every step.

3
CONTENT
Chapter Title Page No.
No.

1. Introduction to biofuel 1

1.1 Classifiation 2

1.1.1 First generation 3

1.1.2 Second generation 5

1.1.3 Third generation 9

2 Classification of Vegetable based fuel

2.1 Biodiesel 10

2.2 Bioethanol 11

3 Biodiesel

3.1 Introduction 13

3.2 Obtaining biodiesel 13

4 Bioethanol 15

4.1 Main challenges for commercialization of lignocellulosic 17

ethanol production
5 Hydrogen as a biofuel

5.1 Main characteristics 19

5.2 Obtaining Hydrogen 20

5.3 Novel technologies for hydrogen production 21

5.4 Hydrogen produced on board the vehicle 22

6 Case study

6.1 Hydrogen as a fuel 23

4
 6.1.1 Maxda red hydrogen 23

6.1.2 BMW 7 series hydrogen 23

6.2 Bioethanol as a fuel 25

6.2.1 Isle of arran 25

6.2.2 Malawi a case study 27

7 Summary 30

8 References 31

List of tables:
Chapter Title Page No.
No.

1. Types of biofuel 2

List of Figures:
Chapter Title Page No.
No.

1. Figure 1: 1st generation 4

2. Figure 2: 1st generation 4

3 Figure 3: Bio vs thermo way 5

4 Carbon cycle 12

5
 Abstract

Development of biofuels from renewable resources is critical to the sustainability of the world’s
economy and to slow down the global climate change. Currently, a significant amount of
bioethanol and biodiesel are produced as biofuels to partially replace gasoline and diesel,
respectively, in the transportation sector worldwide. However, these biofuels represent a tiny
portion (<4%) of the total fuels consumed. Furthermore, bioethanol is produced predominantly
from sugarcane and corn, and biodiesel from crop and plant oils. Production of these raw
materials is competing for the limited arable land against food and feed production. It is not
feasible to tremendously increase biofuel production using the current technologies. Therefore, it
is critical to investigate advanced or 2nd generation biofuel production technologies.. Biodiesel
and bioethanol are the two potential renewable fuels that have attracted the most attention. The
efficiency of ethanol production has steadily increased and valuable co-products are produced,
but only tax credits make fuel ethanol commercially viable because oil prices are at an all-time
low. The original motivation for fuel-ethanol production was to become more independent of oil
imports; now, the emphasis is on its use as an oxygenated gasoline additive

Keywords-biofuels,bioethanol,hydrogen

6
1.Introduction to Biofuels

Biomass has always been a reliable source of energy, from the first man-made fire up to the
utilization of pelletized wood as a feed for thermal plants. Although the use of lignocellulosic
feedstock as a solid biofuel is a well-known concept, conversion of biomass into liquid fuel is a
considerable challenge, and the more complex the biomass gets (in terms of chemical
composition) the more complicated and generally expensive the conversion process becomes.
Depletion of the oil stocks combined with the increasing worldwide energy demand have
generated an increased interest toward biofuels in the last 10 to 20 years, although for most of the
20th century, research on biofuel closely followed the price of petroleum.
With the growing concerns about the greenhouse gas emissions, the use of biofuels, although
sometimes criticized, is often a more environmentally friendly option because the carbon balance
of biofuel is close to neutral when compared with petroleum-derived fuels such as gasoline,
diesel, or kerosene.
Biofuels by definition are fuels that are generated from biological material, a concept that has
recently been narrowed down to renewable sources of carbon. Use of ethanol for lamp oil and
cooking has been reported for decades (called spirit oil at the time) before Samuel Morey first
tested it in an internal combustion engine in early 19th century. Ethanol then replaced whale oil
before being replaced by petroleum distillate (starting with kerosene for lighting). [2]
By the end of the 19th century, ethanol was used in farm machinery and introduced in the
automobile market. Oil-derived products replaced ethanol for most of the 20th century before
being introduced again during the Arab oil embargo in the 1970s when the price of petroleum
and its derivatives peaked.
Ethanol is one of the best known biofuels in the Americas, although other biofuels, mostly
biodiesel, are commonly used in other parts of the world such as Europe, Asia, and increasingly
in Brazil. Both ethanol and biodiesel are considered as first-generation biofuels, although other
types of biofuels like cellulosic ethanol and dimethyl ether (bioDME) are emerging, which could
be characterized as second and third-generation biofuels.[2]
Biofuels, in conjunction to their positive carbon balance with regards to fossil fuels, also
represent a significant potential for sustainability and economic growth of industrialized
countries because they can be generated from locally available renewable material.

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Biofuel issues
� Production costs of biofuels vary according to resource and conversion technology, but
midrange projections suggest that advanced technologies could achieve costs that are around
three times current petrol and diesel costs. This ignores the value of co-products which are
derived from some biomass conversion processes.
� Biofuel chains have CO2 emissions as a result of fertilisers and transport inputs, despite their
combustion CO2 being offset by that absorbed in the growing cycle. The variation between
chains is wide, but tends to be lower from the more advanced technologies.
� Biofuels are already traded internationally to a small extent, mainly originating in
the US and Brazil

1.1: Biofuels are usually classified as follows:

1. First-generation biofuels are directly related to a biomass that is generally edible.
2. Second-generation biofuels are defined as fuels produced from a wide array of different
feedstock, ranging from lignocellulosic feedstocks to municipal solid wastes.
3. Third-generation biofuels are, at this point, related to algal biomass but could to a certain
extent be linked to utilization of CO2 as feedstock.
Scaling second and third-generation biofuel processes thus requires solid economics that are
directly dependent on optimized carbon utilization that relies on the production of fuels
(commodities), as well as high value co-products.

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 Biofuel type Specific name Feedstock Conversion
Technologies
Bioethanol Cellulosic Lignocellulosic Advanced hydrolysis
bioethanol biomass and & fermentaion
biowaste

Biogas SNG (Synthetic Lignocellulosic Pyrolysis/Gasification

Natural Gas) biomass
and residues

Biodiesel Biomass to Liquid Lignocellulosic Pyrolysis/Gasification

(BTL), Fischer- biomass and & synthesis
Tropsch (FT) residues
diesel, synthetic
(bio)diesel
Other Biomethanol, Lignocellulosic Gasification &
biofuels heavier (mixed) biomass synthesis
alcohols, and residues
biodimethylether
(Bio-DME)
Biohydrogen Lignocellulosic Gasification &
biomass and synthesis or biological
biowaste process

Table:1 Biofuel type

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1.1.1 First-generation Biofuels
First-generation biofuels include ethanol and biodiesel and are directly related to a biomass that
is more than often edible. Ethanol is generally produced from the fermentation of C6 sugars
(mostly glucose) using classical or GMO yeast strains such as Saccharomyces cerevisiae.
Only a few different feedstocks, mostly sugarcane or corn, are actually used for the production of
first-generation bioethanol. Other more marginal feedstocks that are used or considered to
produce first-generation bioethanol include but are not limited to whey, barley, potato wastes,
and sugarbeets. Sugarcane is a common feedstock for biofuel production, Brazil being one of the
leading countries for its use.
The process that allows the production of ethanol out of sugarcane is rather simple. The
sugarcane is crushed in water to remove sucrose, which is then purified either to produce raw
sugar or ethanol. Although very advantageous for the producers, increases in the sugar price are
a problem for the bioethanol business. Raw sugar is the other major source of carbohydrates for
production of ethanol, although unlike sugarcane, corn requires a preliminary hydrolysis of
starch to liberate the sugars that can then be fermented to ethanol. The enzyme generally used for
hydrolysis of starch, a-amylase, is rather inexpensive at US$0.04 per gallon of ethanol produced.
Moreover, the value of the by-products, like post-distillation spent grain used for livestock feed,
is a net asset for the whole economical balance of the process
Biodiesel is the only other biofuel produced on an industrial scale. The production process of this
biofuel is very different from ethanol because it could be considered as a chemical process. Of
course, it uses biomass (oily plants and seeds), but the process itself relies on extracting the oils
and converting them into biodiesel by breaking the bonds linking the long chain fatty acids to
glycerol, replacing it with methanol in a process called transesterification.
A simplified version of the lipids used for the production of biodiesel is presented in Figure 2.
Oil price on the international market varies among vegetable sources. As an example, in August
2012, soybean oil market value was US$1,230/t while palm oil was US$931/t. Canola oil,
another common feedstock for the production of biodiesel, had a market value of US$1,180/t.
Based on the latter, it can be roughly estimated that each ton of oil will produce between 1,000
and 1,200 L of biodiesel with a market price estimated from diesel at US$3.2077/gallon
(US$0.85/L).

10
Production of biodiesel also requires methanol (typically between 125 and 150 L/t of oil
converted) at an approximated market price of US$0.35/L. The price for feedstock is the most
crucial factor affecting biodiesel production. Therefore, use of other less expensive sources such
as used oils (US$331/ton) and oil from non-edible plants like jatropha (estimated between
US$350 and US$500/ton) is gaining interest.
Algal biomass is also considered as a source of lipids for production of biodiesel, although it is
generally related to third-generation biofuels. Production of ethanol from sugarcane or corn and
biodiesel from edible oils depends on the prices dictated by the international market, whereas the
prices of used cooking oil and jatropha are presently not influenced by such market, which is a
good incentive for their use for biodiesel production. The availability of such oils is somehow
less than the classical canola or soybean oil. Moreover, residual cooking oil requires additional
processes for purification, whereas production of jatropha could be limited by its low market
value which would not be appealing for production on good arable land, making it economically
viable only on marginal land.[2]

Fig 1: Saccharomyces cerevisiae Fig 2 enlarged view of Saccharomyces cerevisiae

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1.1.2Second-generation Biofuels

Second-generation biofuels are defined as fuels produced from a wide array of different
feedstocks, especially but not limited to non-edible lignocellulosic biomass. Biomass used for
production of second-generation biofuels is usually separated in three main categories:
homogeneous, such as white wood chips with a price value of US$100 to US$120/t; quasi-
homogeneous, such as agricultural and forest residues pricing between US$60 and US$80/t; and
non-homogeneous, including low value feedstock as municipal solid wastes (between US$0 and
US$60/ton) as reported.[2]
The price for this biomass is significantly less than the price for vegetable oil, corn, and
sugarcane, which is an incentive. On the other hand, such biomass is generally more complex to
convert and its production is dependent on new technologies. Biofuel production is linked to the
commodity market; consequently, the cost of converting the original feedstock to the final
product must be as low as possible to maintain profitability.
On the other hand, many biomasses (e.g., corn with the ethanol/livestock feed duality) allow the
opportunity to generate a variety of products out of the same feedstock, thus adhering to the
concept of a “biorefinery.”
The conversion process for production of second-generation biofuels is usually done according
to two different approaches, generally referred to as “thermo” or “bio” pathways. A simplified
scheme of the second-generation biofuel production pathways is depicted in Figure 3.[2]

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Fig 3:Bio vs thermo way

The “thermo” pathway

The “thermo” approach covers specific processes where biomass is heated with a minimal
amount of oxidizing agent, if any. All processes in that category lead to conversion of biomass
into three fractions: one solid known as biochar, one liquid currently referred to as pyrolytic oil
or bio oil, and one gas known as syngas, which is usually composed of carbon monoxide,
hydrogen, short chain alkanes, and carbon dioxide.
When processed at low temperatures (250 to 350°C) without oxygen, biomass undergoes a
torrefaction process and the major conversion product is biochar.
At greater temperatures (550 to 750°C), also without oxygen, the process is known as pyrolysis
(either fast or slow depending on the heat exchange rate with the biomass) and the major product
is bio oil.
At greater temperatures (750 to 1,200°C) and with limited inputs of oxygen, gasification occurs
producing mostly syngas with biochar and bio oils as by-products.

13
Thermal processes are to a certain extent self-sufficient in terms of energy because the energy
required to heat the biomass up to the requested temperatures can be supplied by the partial or
total oxidation of carbon from the biomass, reactions that are usually very exothermic.
Biochar, considered as a solid biofuel, is gaining a lot of attention in the pelletizing business,
especially in parts of the world where lignocellulosic biomass is rather inexpensive.
Nevertheless, for transportation fuel, production of pyrolytic oil or syngas is usually considered
as more promising intermediaries. Pyrolytic oil is a liquid intermediary which, to a certain
extent, looks similar to petroleum but is very different chemically. Therefore, to produce
transportation fuel from this intermediary, a second transformation must be made, which is a
rather difficult task because of the high water content as well as the corrosive nature of bio oil.
Zhang et al. (2007) reviewed the four most promising processes for this transformation:
1) hydrodeoxygenation (reducing the amount of oxygen produces a mixture of alkanes similar to
petroleum)
2) catalytic cracking
3) steam reforming and
4) the creation of an emulsionwith diesel
Gasification, in contrast to pyrolysis, produces syngas, mostly composed of single carbon
compounds and hydrogen. Nevertheless, although production of transportation fuels is possible
out of syngas, it relies on the use of complex catalysts to induce the production of carbon-carbon
bonds. A typical example of such process is the Fisher-Tropsh process.One of the simplest
approaches for the industrial production of synfuels out of syngas is to produce methanol.
Methanol can be produced from carbon monoxide and hydrogen directly under the action of a
reducing catalyst. Methanol is an end product of its own but it cannot be used as additive for fuel
at this point. [2]
Therefore, further transformation is required. Relying on methanol as the starting material, many
end products have been produced including alkanes via the methanol-to-gasoline (MTG) process,
and ethanol via carbonylation processes. Methanol is also investigated for the production of a
new generation of fuels such as Biobased Di-Methyl ether (bioDME), produced through
etherification of two methanol molecules. It has been reported as an additive to diesel and has the
distinctive advantage of being simple to produce under the action of an acid catalyst. However,
BioDME has specific properties that tend to limit its use in the transportation fuel market,

14
specifically because of its low viscosity compared with diesel fuel causing excessive wear in fuel
injection systems. Even if all carbon-based biomasses could in theory be converted to biofuels
using any of the “thermo” processes, certain technical and economical restrictions apply.
For example, gasification processes lead to the production of syngas and ultimately to
transportation fuel (e.g., ethanol). The typical quantity of ethanol produced per ton of biomass is
360 L, with the price of ethanol at US$0.68/L and a production price close to US$0.30/L.
Therefore, the process is highly dependent on the feedstock price because the conversion from
biomass to syngas, the purification of syngas, and the catalytic synthesis of ethanol represent
significant technological challenges. Therefore, the most homogeneous and expensive biomasses
would not be good candidates for such technology. Biomasses such as quasi-homogeneous or
non-homogeneous would be more suitable.

The “bio” pathway

The “bio” pathway is somewhat comparable with a pulping process because, in most cases,
cellulose is first isolated from the lignocellulosic biomass. Many processes have been
considered, including classical pulping processes, steam explosion, and organosolv processes.
Isolation of cellulose is a technological challenge because it has to produce the highest purity of
cellulose to remove most inhibitors without consuming too much energy or too many chemicals.
Once purified, two approaches are generally used for saccharification of cellulose: either
enzymatic or by chemical hydrolysis using acids. In both cases, there are some limitations to the
processes, mostly from an economical point of view as the price of the enzymes is forecasted to
reach US$0.12 to US$0.20/L of ethanol produced in 2015. On the other hand, chemical rocesses
rely on rather inexpensive chemicals (e.g., sulfuric acid), although they have to be recuperated at
a low cost to keep the process economically viable. Once isolated, the macromolecule (i.e.,
starch) requires hydrolysis to be fermented by yeasts. The saccharification of cellulose is a rather
expensive process, there is a dire necessity to maximize the conversion of the biomass, such as
using hemicellulose, lignin, and other extractives.
Hemicelluloses are highly ramified carbohydrate-based polymers composed of both C5 and C6
sugars and account for 15 to 25% of the lignocellulosic biomass (dry weight). Usually, the ratio
between xylans and glucans in hemicelluloses varies from 50 to 75% of the total carbohydrate
content. The main advantage of hemicelluloses is that, due to their highly ramified structure, they

15
can be hydrolyzed easily using water at high temperatures or a very diluted aqueous mixture of
acids.
The key problem is that C5 sugars do not ferment with classical yeast strains and require
genetically modified organisms to produce ethanol. Furthermore, acids (both acetic and formic)
may inhibit the fermentation process, requiring an additional operation for detoxification.
Another approach for valorization of C5 sugars could be via chemical pathways .
Many researchers have been working on this specific approach in which C5 sugars like xylose
are dehydrated to furfural (4A), which acts as a platform chemical and an intermediary from
which drop-in fuels such as methyl tetrahydrofuran (Figure 4B) and ethyl levulinate (Figure 4C)
could be produced.
Lignin, the second most abundant natural polymer found at 25 to 35% (dry weight) in
lignocellulosic biomass .is mostly composed of phenyl propane units. The macromolecule is
highly energetic and has been used for cogeneration or as a fuel by the pulp and paper industry.
Although they could be used as fuel or as a source of hydrogen in a biorefinery
process, the aromatic monomers from lignin could also be a very abundant source of high value
chemical compounds that could be used in the plastic industry, as well as adhesives. In both
cases, industrial-grade aromatics are actually obtained as side-products from petroleum.
Consequently, the use of biomass to produce such monomers (or green chemicals) would lead to
an interesting new market for bioadhesives and second-generation bioplastics. Recent work by
our team has shown that it is possible to convert 10 to 20% weight of lignin into added value
compounds such as guaiacol, cathecol, and phenol . Reported work on lignin has also shown that
it is possible to convert part of it into transportation fuels such as jet fuel .

16
1.1.3Third-generation Biofuels

The most accepted definition for third-generation biofuels is fuels that would be produced from
algal biomass, which has a very distinctive growth yield as compared with classical
lignocellulosic biomass .Production of biofuels from algae usually relies on the lipid content of
the microorganisms. Usually, species such as Chlorella are targeted because of their high lipid
content (around 60 to 70%)and their high productivity (7.4 g/L/d for Chlorella protothecoides.
There are many challenges associated with algal biomass, some geographical and some
technical. Typically, algae will produce 1 to 7 g/L/d of biomass in ideal growth conditions. This
implies large volumes of water are re uired for industrial scale, presenting a ma or problem for
countries li e anada where the temperature is below C during a significant part of the year. The
high water content is also a problem when lipids have to be extracted from the algal biomass,
which requires dewatering, via either centrifugation or filtration before extracting lipids. Lipids
obtained from algae can be processed via transesterification by the previously described
biodiesel process or can be submitted to hydrogenolysis to produce kerosene grade alkane
suitable for use as drop-in aviation fuels [7]
.

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2:Vegetable Based fuels
Many vegetable oils have similar properties to Diesel fuel, except for lower oxidative stability
and higher viscosity. If these handicaps can be overcome, vegetable oils may substitute diesel
fuels. Vegetable oils are often referred to as Waste vegetable oil (WVO) if it is oil discarded
from restaurants, or Straight vegetable oil (SVO) to distinguish it from biodiesel. It is important
to clarify the difference between vegetable oil used as a fuel and vegetable oil used to get
biodiesel. Unfortunately, the first one is often referred to as biodiesel, although such a
denomination is incorrect. As an interesting fact, it might be mentioned that best known
vegetable oils are those extracted from hemp seeds and stalks. Such crops are becoming more
and more popular.

2.1:Biodiesel
The word biodiesel refers to any diesel equivalent processed fuel, derived from biological
sources. Therefore, it is a processed fuel which is ready to be used in common diesel-engined
vehicles, used as fuels in some modified diesel vehicles. Despite it contains no petroleum;
biodiesel can be blended at any level with petroleum diesel to create a biodiesel blend. Little or
no modifications are needed to use it in common compression-ignition diesel engines.

Production process

Biodiesel can be produced via two principal routes:

1. The extraction of oil from seeds or oil-rich nuts followed by its esterification.
2. The purification and esterification of recovered waste vegetable oils and animal fats.
This is more complex than for pure vegetable oils such as rapeseed oil, as the greater
concentration of free fatty acids and impurities, such as water, need to be treated or removed.
The blending of vegetable oils with diesel at the refinery is also an option.

Feedstock

Biodiesel can be produced from all oil producing crops. In the UK, rapeseed and sunflower are
the principal potential sources of biodiesel. Rapeseed represents more than 80% of current global

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biodiesel production, sunflower 13%, soya bean 1% and palm oil 1%. Recovered cooking oils
and animal fats are another source of biodiesel production.

Fuel quality and specifications

The esterified vegetable oils produce a fuel with physical properties similar to those of mineral
diesel, with some key differences. Biodiesel has a lower energy content than mineral diesel and
around a 10% loss in power can be expected in vehicles powered with 100% biodiesel compared
to mineral diesel. It has better lubricant properties than modern ultra low sulphur diesel. It is
corrosive to rubber, so that components in the fuel delivery systems need to be replaced with
resistant alternatives.

BioEthanol
Working principle

Bioethanol is an alcohol product produced from corn, sorghum, potatoes, wheat, sugar cane,
even biomass such as cornstalks and vegetable waste. When combined with gasoline, it increases
octane levels while also promoting more complete fuel burning that reduces harmful tailpipe
emissions such as carbon monoxide and hydrocarbons.
Bioethanol is a readily available, clean fuel that can be utilized in combustion
engines in different ways:
Hydrous ethanol (95 percent by volume) contains some water. It is used directly as a gasoline
substitute in cars with modified engines. Anhydrous (or dehydrated) ethanol is free of water and
at least 99 percent pure. This ethanol can be blended with conventional fuel in proportions of
between 5 and 85 percent (E85). As a 5 percent additive it can be used in modern engines
without modification. Higher blends require modified engines as run on so-called flexible fuel
vehicles. Finally, BioEthanol is also used to manufacture ETBE (ethyl-tertiarybutyl- ether), a
fuel additive for conventional petrol. To be able to use the BioEthanol as pure fuel (E100) they
need to take to end a series of modifications in the engine, not to alter significantly the
consumption; These are:
 To increase the relation of compression.

19
  To change the mixture of fuel / air.
 To place spark plugs resistant to major temperatures and pressures.
 To place conduits resistant to the assault of tar after caulking.
 To add a mechanism that should facilitate the take-off in cold.
The most common and simple form of utilization of this fuel is in partial form up to 15 % (E10
or E15) without being a necessary any modification in the engine, though small modifications in
the relation of compression and relation air / fuel, it can improve the power. As the attaché of
alcohol increases in the mixing, the combustion liberates pollutants' minor quantity to the
atmosphere, especially CO
PROs of using BioEthanol

 As it is domestically produced, its use can reduce dependence on imported oil and boost
the agricultural sector.
 Its burning is about 10 % more efficient than gasoline’s.
 FFVs are available and becoming more affordable.

CONs of using BioEthanol

 Ethanol has less energy content than gasoline. Therefore, more fuel is needed to run the
samen distance.
 Fueling stations are yet difficult to find.
 Production is yet limited, although it is growing rapidly. Infrastructure for fueling and
 distribution is yet insufficient.
 It will take time to automotive and fueling industries to develop the required
infrastructure.

20
  Fig 4 carbon cycle

An Example Of Bioethanol Combustion Consumer Car:

Ford Focus FFV

Ford is to become the first major manufacturer to launch a bioethanol powered car in the UK
when deliveries of the Focus FFV begin in early 2006. The first FFV is currently being tested in
Somerset, where locally-grown wheat is being used to produce the bioethanol fuel that powers its
1.8-litre engine. The FFV produces 70 per cent less carbon dioxide than its petrol equivalent, and
develops 123bhp. The car runs either on E85 bioethanol fuel, which is a mix of 85 per cent
ethanol and 15 per cent petrol, or on petrol. Initially the Focus FFV will be available only as a
fleet purchase, priced at £14,095, although it may become available.[7]
Fig 5 Ford focus

21
Chap 3:Biodiesel
3.1 Introduction
Biodiesel constitutes a group of biofuels that are obtained from vegetable oils as soy, rape and
sunflower (two main cultivations of oily in the European Union). The biodiesel are mono-alkyl
esters of the vegetable oils obtained by reaction of these with methanol, by means of reaction of
transesterification which produces glycerin as secondary product. The physical properties of
mono-alkyl esters are so similar to those of common diesel that both can be mixed in any
proportion to be used in conventional diesel vehicles. What is more, there is no need to introduce
modifications in the basic design of the engine. Nevertheless, it is necessary to swap the rubber
conduits of the car into viton ones when biodiesel proportion in the mix is higher than 5%. This
is due to biodiesel attacking the first. As opposed to ethanol, the mixtures with biodiesel do not
modify very significantly great part of the physiochemical and physical properties of the diesel
oil, such as their calorific power.

3.2 Obtaining biodiesel

The process of transesferification consists of mix the oil with aglycerin which the industry can
take advantage from. The source of vegetable oil is used to being oil of rape, since is a species
with high content of and other cosmetica light alcohol, normally metanol, and leaves as residues
of value addition Oil, that adapts well to the climates colds. Nevertheless other varieties with
greater performance exist by hectarea, such as the palm, the jatropha curcas etc. Also oils used
can be utilized (for example, oils of fried food), in whose case the commodity is very cheap and,
besides, they recycle themselves what in another case would be residues.

The biodiesel does not count in the carbon dioxide production because is supposed that the plants
absorbed that gas in their growth, so, because of it, aid to contain the mission of greenhouse
gases. In reality the account is not so simple, therefore the metanol that is employed in its

22
production is used to obtaining itself of the petroleum, for which the balance of CO2 is not nil. It
would be able to obtain metanol of the wood, that serious a renewable source; nevertheless turns
out to be more costly. On the other hand, the glycerin can also burn, therefore neither its
combustion counts in the production of CO2.

PROs of using biodiesel as an alternative fuel

 Biodiesel is produced from oilseed crops, animal fats and waste cooking oils.
 Emissions from using biodiesel are far cleaner than those of diesel.
 Biodiesel reduces waste oils that otherwise would have to be disposed.
 Biodiesel can be locally produced, which rises local economies.

CONs of using biodiesel as an alternative fuel

 Some users have reported problems when using biodiesel at low temperatures
 There is a slight increase in nitrogen oxide (NOx) emissions. Additives are being
researched to solve the problem.

Biodiesel production over the world

A very wide range of crops are used for small-scale biodiesel production around the world, but
there are a few popular choices. The first, and most common, was rapeseed or canola. Rapeseed-
oil is an ideal raw material for a European climate which tends to have cold winter conditions.
Other raw materials used are palm-oil in Malaysia and sunflower oil in France and Italy while
soybean-oil became the raw material of choice in the USA. In Nicaragua the locally available oil
of Jatropha curcas plant is processed.

23
This table show the world’s leading biodiesel productions.[9]

Country capacity install (tn/year 2000) Production(tn/year 2000)

Germany 550.000 415.000
French 290.000 286.000
Italy 240.000 160.000
Belgium 110.000 86.000
England 2.000 2.000
Austria 20.000 20.000
Sweden 11.000 6.000
Total 1.270.000 1.005.000

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4: Bioethanol
Lignocellulosic ethanol production

Bioethanol can be produced from different natural materials: sugar-, starch-, and lignocellulose-
based materials. Currently bioethanol is produced predominantly from sugarcane and corn.
However, production of these raw materials is competing for the limited arable land against food
and feed production. It is not feasible to tremendously increase bioethanol production using the
current technologies. Lignocellulosic materials are abundant almost all over the world and they
can be used for bioethanol production because they have a high content of cellulose and
hemicelluloses. However, the conversion of lignocellulosic materials to ethanol is much more
difficult than that of sugar-rich or starch-rich materials. The conversion of lignocelluloses to
ethanol involves three steps: pretreatment, hydrolysis, and fermentation.

Lignocellulose

Lignocellulose is composed of mainly cellulose, hemicelluloses, and lignin. Cellulose is a long-

chain homogenous polysaccharide of D-glucose units linked by b-1,4 glycosidic bonds and
contains over 10,000 glucose units. Hemicellulose is a complex, heterogeneous polymer of
sugars and sugar derivatives which form a highly branched network and the monomers include
hexoses (glucose, galactose, and mannose) and pentoses (xylose and arabinose). It consists of
about 100e200 sugar units. Lignin is a very complex heterogeneous mixture of mainly phenolic
compounds and their derivatives. It is a main component in plant cell walls. Lignin holds the
cellulose and hemicellulose fibers together and provides support to the plants.

Pretreatment

Pretreatment is the process to prepare the ligocellulosic materials for the enzymatic hydrolyses of
cellulose and hemicelluloses to generate fermentable sugars. The purpose of the pretreatment is
to separate the lignin from cellulose and hemicelluloses in the lignocellulose, reduce cellulose
crystallinity, and increase the porosity of the material, so the hydrolytic enzymes can access their
substrates (cellulose and hemicellulose) in the following enzymatic hydrolysis. Pretreatment
technologies have been extensively investigated in the last three decades, including physical,
chemical, and biological processes for lignocellulosic materials .

25
Physical pretreatment

Physical pretreatment includes mechanical comminution, steam explosion, ammonia fiber

explosion, and pyrolysis. mechanical comminution combines chipping, grinding, and milling to
break the lignocellulosic materials down to 0.2e2 mm and reduce the crytallinity of the materials.
Steam explosion applies high-temperature (160e260 _C) and highpressure saturated steam to
steep the lignocelluloses and swiftly release the pressure to atmospheric, causing explosive
decompression which separates lignin from the carbohydrates and degrade the hemicelluloses.
Similar to steam explosion, ammonia fiber explosion uses liquid ammonia to soak the
lignocellulosic materials at high temperature (around 100 _C) for a period of time and then the
materials are swiftly flashed to a low pressure, breaking the chemical bonds between lignin and
cellulose and hemicelluloses and substantially increasing the porosity of the materials. In
pyrolysis, the lignocellulosic materials are exposed to a high temperature (over 220 _C). At that
temperature, the hemicelluloses and some lignin and cellulose will be degraded to gaseous and
tarry compounds and the tight structure of the lignocelluloses will be broken. Physical
pretreatment can effectively break the structure of the lignocellulosic materials and substantially
improve sugar yield in the following enzymatic hydrolysis. However, physical pretreatment
usually involves high energy input

Chemical pretreatment.
Commonly used chemical pretreatment technologies include acid and alkaline hydrolyses. Dilute
sulfuric acid pretreatment applies high temperature (140e190 _C) to the mixed slurry of the
lignocelluloses and the acid. The acid decomposes the hemicelluloses at that temperature,
resulting in a breakup of the lignocellulosic structure. Most hemicelluloses are degraded into
sugars which stay in the liquid portion, while cellulose remains in the solid portion. The main
disadvantage of dilute acid pretreatment is the formation of chemicals such as furfurals during
the degradation of hemicelluloses that inhibit the following enzymatic hydrolysis and microbial
fermentation. Alkaline hydrolysis is another chemical pretreatment method at high temperature
(100e170 _C). During the alkaline pretreatment, there are saponification reactions of
intermolecular ester bonds crosslinking hemicellulose and cellulose or lignin in the
lignocellulosic materials. Alkaline pretreatment can also disrupt lignin structure, decrease

26
crystallinity of cellulose and degree of sugar polymerization. Although alkaline pretreatment
could cut the bonds between lignin and cellulose or hemicelluloses, a significant portion of lignin
still remains mixed with cellulose after the pretreatment. The existence of lignin may inhibit
cellulase enzymes during the following enzymatic hydrolysis.

Biological pretreatment.
Biological pretreatment processes use microbes such as brown-, white- and soft-rot fungi to
degrade lignin and hemicellulose in lignocellulosic materials. Brown rots mainly attack
cellulose, while white and soft rots attack both cellulose and lignin. White-rot fungi are the most
effective basidiomycetes for biological pretreatment of lignocellulosic materials. Biological
pretreatment is probably the most economical pretreatment technology for the lignocellulosic
materials. However, it is also a very time consuming process. The pretreatment usually takes a
few weeks.

Enzymatic hydrolysis
Enzymatic hydrolysis of pretreated lignocellulosic materials involves enzymatic reactions that
convert cellulose into glucose, and hemicellulose into pentoses (xylose and arabionose) and
hexoses (glucose, galactose, and mannose). The conversion of cellulose and hemicellulose is
catalyzed by cellulase and hemicellulase enzymes, respectively. The enzymes are highly specific.
The enzymatic hydrolysis is usually carried out at mild conditions (pH 4.8 and temperature
45e50 _C). Cellulases or b-(1-4) glycoside hydrolases are a mixture of several enzymes and at
least three major groups of cellulases are involved in the hydrolysis of cellulose: endoglucanase,
exoglucanase, and b-glucosidase. After the pretreatment, most of lignin is removed from the
lignocellulosic materials, the crystallinity of the materials is significantly reduced, and the
porosity is substantially increased, which allows the enzymes to penetrate into the materials and
access the substrates. Endoglucanase randomly attacks regions of low crystallinity in the
cellulose fiber and hydrolyze the b-(1, 4) glycosidic bonds of cellulose to produce
cellooligosaccharides with free-chain ends. Exoglucanase can hydrolyze the b-(1, 4) glycosidic
bonds from the non-reducing ends of the cello-oligosaccharides to generate cellobiose which is
further hydrolyzed by b-glucosidase to glucose.

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4.1 Main challenges for commercialization of lignocellulosic ethanol
production

Ethanol production costs need to be further reduced for the commercial application of the 2nd
generation ethanol technologies. Most pretreatment processes produce an increase in glucose
yield from enzymatic hydrolysis, indicating expansion of the matrix and/or varying degrees of
removal of hemicellulose and lignin . However, the high cost of some pretreatments and the low
bulk densities of most lignocellulosic materials make them uneconomical to pretreat or to
transport to centralized facilities for processing. Reducing these costs before reaching the
processing stage is desirable to allow use of these annually renewable materials.
Although pretreatment could significantly increase the yield of glucose and soluble sugars in the
enzymatic hydrolysis, the key to successful hydrolysis is the cellulase enzymes. Industrial
preparations of the cellulase enzymes are normally obtained from fungal and bacterial origins .
These enzymes are usually very expensive, which makes the ethanol production from
lignocellulosic biomass not economically competitive. It is critical to develop low-cost cellulase
production systems to reduce the cost for lignocellulosic ethanol production. Another challenge
for the commercialization of lignocellulosic ethanol production is to efficiently utilize the
lignocellulosic materials. In the sugar- and starch-based ethanol production technologies, almost
all the sugars and starch are converted to ethanol. However, the conversion rate of
lignocelluloses to ethanol is much lower, in the range of 30e60% depending on the technologies.
Among the three major components of lignocelluloses, cellulose has the highest conversion rate
to ethanol, 85e90%; hemicelluloses 30e85%; lignin; 0%. The main products of hemicellulose
hydrolysis include hexoses and pentoses. The former can be readily fermented to ethanol by
yeast or bacteria, but the latter is difficult. To make the lignocellulosic ethanol production
economically feasible, it is necessary to utilize the hemicelluloses which is about one third of the
biomass. In other words, it is critical to develop cost-effective technologies to ferment both
hexose and pentose into ethanol. Lignin is very tough to be converted to ethanol, but it can be
used as a fuel in the fractional distillation in ethanol purification. To overcome the barriers of
lignocellulosic ethanol production, more research is needed in feedstock, pretreatment, cellulase
enzyme production, and new fermentation technologies.

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The research in developing cost-effective technologies for the 2nd generation ethanol production
need to be focused on the following areas:

(1) Feedstock Development: Lignocellulosic materials such as corn stover, switchgrass, and
poplar trees can be genetically modified for lower lignin and higher cellulose contents. Lower
lignin content in the lignocellulosic materials could substantially reduce the severity of the
pretreatment process or even eliminate the process. Some success has been reported in
genetically reducing lignin content in aspen trees, but more research is necessary to have stable
low lignin woody biomass production of the trees in the field (Chiang, personal communication).
(2) Pretreatment Technology: Current pretreatment technologies usually involve high
temperature or high pressure, which result in a high cost of the process. Low-cost low-
temperature pretreatment is a promising technology for the pretreatment of lignocellulosic
materials and need more research and development.
(3) Enzyme Cost Reduction: Although the cellulase enzyme cost has been significantly reduced
in the last decade, it is still high in comparison with amylases (the enzymes used in starch to
ethanol process). Microorganisms that have high-efficiency in cellulase enzyme generation need
to be explored to improve the enzyme fermentation process. Novel technologies may be needed
to significantly reduce the cost of cellulase enzymes.
(4) Co-Fermentation of Glucose and Xylose: Glucose is the main product of enzymatic
hydrolysis of cellulose, while xylose is a main product of hemicellulose hydrolysis. Fermentation
of glucose to ethanol is a mature technology, but converting xylose to ethanol is quite
complicated. There have been some efforts in developing genetically engineered microorganisms
(yeast and bacteria) that can efficiently convert both glucose and xylose to ethanol, but more
research needs to be done in this area.[8]

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5:Introduction to hydrogen
Hydrogen is a colourless, odourless, non-toxic flammable gas, with no local pollutant effects. It
is not a greenhouse gas, but is only found in useful quantities on earth in compound forms, such
as water or hydrocarbons. Hydrogen can be used as a transport fuel, in internal combustion
engine (ICE) or fuel cell (FC) vehicles. Hydrogen must be produced using primary energy, then
stored and transmitted before it can be converted to an energy service in an end-use technology
such as a vehicle. Hydrogen is commonly produced from conventional hydrocarbons such as gas,
oil and coal, or from the electrolysis of water. Removal of impurities may then be necessary
before the hydrogen can be used in an energy application. Storage of hydrogen normally takes
the form of compressed gas, though liquefaction is also common, and alternative storage
methods are being developed. Transport is by tanker, barge or train in compressed or liquid form,
or as a gas by pipeline when large amounts are required for a long period of time. Emissions
from hydrogen systems depend mainly on the primary energy source used to produce the
hydrogen, but also on the transport and end-use technologies. Hydrogen is necessarily more
expensive per unit of energy than the source from which it is produced, but if it can be used more
efficiently then the overall cost of the service (e.g. miles driven) may not differ greatly from
conventional fuels. As a highly simplified example, hydrogen produced from natural gas might
cost about twice as much as the natural gas itself. However, burning the natural gas at 20%
efficiency in a standard car engine would still be more expensive than using the hydrogen in a
fuel cell, if the fuel cell has a 50% efficiency. The greater efficiency of the fuel cell in this
example more than cancels out the loss of efficiency in the production process.

5.1:Main characteristics
Hydrogen is the lightest and simple atom in the periodic system, with atomic number 1 and
weight atomic 1.00794 g/mol. In standard conditions of pressure and temperature it is a non-
toxic but very flammable diatomic gas, colourless and odourless. It has a specific gravity of
0.0899g/l (the air is 14,4 times heavier). Its boiling temperature of only 20.27 K (- 252.88 ºC)
and a fusion temperature of 14.02 K (- 259,13ºC). Hydrogen is by far the most common element
in universe. Nevertheless, it does not constitute a directly usable fuel and so it is not an energy
source, but an energy vector. Its power density is three times superior to that from gasoline

30
Pros of using Hydrogen as an alternative fuel

 Low energetic density in volumetric base. Containers tanks are required great and heavy.
 High availability. It can be produced from very different raw materials.
 Stable and non corrosive
 “Clean” fuel. The combustion of hydrogen with oxygen produces just water

CONs of using Hydrogen as an alternative fuel

 Low energetic density in volumetric base. Container tanks are required great and heavy
 Both transport and storage are expensive and of a complex installation.

5.2:Obtaining Hydrogen

Hydrogen can be produced by electrolysis, splitting water into hydrogen and oxygen. The
electricity needed for this process can be provided from renewable sources such as wind, tidal,
wave, hydro, or solar energy, and so hydrogen can be produced with zero arbon dioxide
emissions. Thermal decomposition of water is possible in principle, though it requires very high
temperatures. Hydrogen can also be produced directly from biomass products, through
fermentation, gasification and/or digestion, followed by a series of chemical reactions to strip out
the hydrogen. Carbon dioxide is released in this process, but this is offset by the carbon dioxide
absorbed in replacement biomass growth. Other production routes are the photo-biological
splitting of water using bacteria and algae via a natural photosynthetic process.

Steam reforming

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Hydrogen is obtained from hydrocarbons, fundamentally from the natural gas. The main
component of natural gas is methane CH4 and the reaction basically consists in separating carbon
from hydrogen.
The process takes place in two stages: In the initial phase, the natural gas becomes hydrogen,
carbon dioxide and carbon monoxide. The second stage consists of producing additional
hydrogen and carbon dioxide from the carbon monoxide produced during the first stage. The
carbon monoxide is heated with a steam current to high temperature obtaining hydrogen and
dioxide carbon. Resulting hydrogen is stored in tanks. Most of hydrogen used by the
petrochemical industry it is generated this way. The process has efficiency between 70 and 90%.

The following global reaction represents the process:

CH4 + H2O => CO + 3 H2

CO + H2O => CO2 + H2

Partial fossil fuel oxidation with defect of O2

A hydrogen mixture is obtained that later is purified. The amounts of oxygen and water steam
are controlled so that the gasificación continues with no need of energy contribution. The
following global reaction represents the process:

1.4 CH4 + 0.3 H2O + 0.4 O2 => 0.9 CO + 0,1 CO2

Electrolysis of water

The passage of the electrical current through water produces dissociation between hydrogen and
oxygen, components of the molecule of water H2O. The hydrogen takes shelter in the cathode
(pole loaded negatively) and oxygen in the anode. The process is much more expensive that the
reformed with steam, but it produces hydrogen of great purity. This hydrogen is used in the
electronic industry, pharmaceutics or nourishing.
H2O + Power => H2 + ½ O2

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Photo electrolysis is a similar process where electrical current comes from sun energy

Biomass can be used as a source for hydrogen by two different procedures.

Gasification of biomass: biomass is put under to a process of incomplete combustion between

700 and 1200ºC. The resulting product is a fuel gas composed fundamentally by hydrogen,
methane and carbon monoxide.
Pyrolysis: It is the incomplete combustion of biomass in oxygen absence, at 500ºC. vegetable
coal and gas mixture of carbon monoxide and dioxide, hydrogen and light hydrocarbons are
obtained.
Photo biologic production
For example, cianobacterium and green seaweed can produce hydrogen, using only solar light,
water and hydrogenasa like an enzyme. At the moment, this technology is in period of
investigation and development with efficiencies of conversion superior to 24%. More than 400
varieties of primitive plants have been identified to produce hydrogen.

Biomass resource categories Examples

Dedicated plantations Short rotation forestry and crops such as
willow. Perennial annual crops such as
miscanthus. Arable crops such as rapeseed.
Residues from primary biomass production Wood from forestry thinning and felling
residues. Straw from a variety of cereal crops.
Other residues from food and industrial crops
such.
By-products and wastes from a variety of Sawmill waste, manure, sewage sludge,
processes organic fractions of municipal solid waste,
used vegetable cooking oil, etc.

5.3 Novel technologies for hydrogen production :

Technologies currently at the research and demonstration stage for hydrogen production that
could be important in the future, but which have not been considered in the modelling, include:
Photosynthetic processes use organisms such as green and blue green algae, or photosynthetic
bacteria, to split water or other compounds to form hydrogen.
Fermentation processes use bacteria to ferment carbohydrate-rich organic material,

33
such as crops or food wastes, under dark, anaerobic conditions, to produce hydrogen
Photochemical processes produce hydrogen by using semiconductor material to
convert energy from sunlight into electrons to decompose water

5.4:Hydrogen production on board the vehicle

Hydrogen on board production out of methanol fuel for its consumption in situ seems to be the
most suitable alternative. The hydrogen can be obtained by three different catalytic routes:
 Partial oxidation with oxygen or air: CH3OH + ½ O2 => CO2 + 2 H2
 Reformed with water steam: CH3OH + H2O => CO2 + 3 H2
 Decomposition: CH3OH => CO + 2 H2
Hydrogen on board production out of ethanol fuel, where the following
reaction takes place:
CH3CH2OH + 3H2O => CO + CO2 + 6H2
In this case carbon monoxide is produced, which is a poison of the membrane of proton
interchange of the fuel batteries. The production of hydrogen from the primary matter
(hydrocarbons or water) needs important amounts of energy. The investigation is centered now
in knowing if the use of renewable energies without carbon is possible: to obtain hydrogen of the
water from photovoltaic, geothermal or hydraulic energy.

Use of hydrogen in automation

Hydrogen can be used in the transport industry in mainly two different ways. It can be used as
fuel in an alternative motor of internal combustion and it can also be used in fuel batteries. In
fuel batteries, electrical energy is obtained from the opposite process to electrolysis and such
energy is used to power an electrical engine. Hydrogen for the process can be obtained in the
vehicle itself (by some of the previously mentioned means) or refuelled at stations. Each one of
these alternatives requires different technology and infrastructure and present advantages and
disadvantages. Therefore, present researches search for the most efficient and economically
affordable method. The investigation field is very extensive, so we will be centered in the present
developments showing some examples and comparing the alternatives.

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Hydrogen combustion in ICEs

Regarding the use of hydrogen, car manufacturers have developed special vehicles in which
traditional internal combustion engines are replaced by electrical engines. In these, energy is
created on board, in the fuel cells out of hydrogen, as explained before. Moreover, some
manufacturers like BMW or Mazda have been trying to go further by developing vehicles that
can work indifferently with hydrogen and normal gasoline.
[9]

35
6: CASE STUDY

6.1 Hydrogen as a fuel

6.1.1 .Mazda Rx8 Hydrogen

In March 2006 Mazda began to commercialize its rotary engine Mazda Rx8 Hydrogen in Japan.
The rotary engines adapts to alternative fuels like hydrogen better than raditional alternative
piston engines. A rotary engine works in four different phases (admission, compression,
explosion and escape), each of which takes place in different cameras. The rotor pushes the fuel
mixture into each of the cameras. By such means, temperatures do not get so high and risk of
detonation is dismissed. The exit to the market of the hydrogen cars is slow because the vehicle
manufacturers wait for hydrogen to be available while at the same time fuel providers wait for
hydrogen vehicles to be operative. So Mazda has prepared its own station that will comprise of a
public network that already prepares the Norwegian State.

6.2.2 BMW 7 Series Hydrogen

BMW will begin to commercialize its own hydrogen car by April 2007. This vehicle has a 12
cylinder alternative engine with a 200 HP power. It has a 140 litre hydrogen deposit, with a 350
km autonomy. In addition, it has conventional fuel feeding due to the incomplete provision
network of hydrogen. What makes the engine different are its particular hydrogen valves.

36
Fuel batteries

Fuel batteries are electrochemical systems where the energy of a chemical reaction turns directly
into electricity. Unlike the electrical battery, a fuel battery does not finish nor needs to be
recharged; it keeps working while fuel and oxidant are provided. A fuel battery consists of two
parts. Fuel – namely hydrogen - is injected in the anode, while oxidant – usually air or oxygen -
is introduced in the cathode. Both electrodes of a fuel battery are separated by a conductive ionic
electrolyte. Its operation principle is the contrary to the one of electrolysis. For example, in water
electrolysis, wateris separated into its two components, hydrogen and oxygen, whereas in a fuel
battery an electrical current would be obtained by means of the reaction between these two
gases:
Hydrogen + Oxygen => Electricity + Water
Manufacturers as General Motors, Toyota, DaimlerChrysler or Ford are working in development
of fuel batteries. Fuel battery vehicles are powered with hydrogen, but the technology is cleaner
since the combustion of a hydrogen mixture with air continues producing some small polluting
emissions (NOx and CO). The fuel battery generates electrical energy used in electrical motors
that drive the wheels of the vehicle. Hydrogen is difficult to store and a hydrogen network does
not exist.In addition, there is no plan to implement one yet. For that reason, some companies
involved in the development of fuel battery advocate to obtain hydrogen inside the car itself,
from a fuel like gasoline or methanol.

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6.2 Bioethanol as a fuel

6.2.1 Isle of Arran

The Isle of Arran lies off the west coast of Scotland in the Firth of Clyde. It is a 42,801-hectare
picturesque island often referred to as ‘Scotland in miniature’ due to the presence of the highland
boundary fault and its geographical similarity to Scotland as a whole. The north end of the island
is mountainous, combining deep glens with peaks rising to 874 m[ at the summit of Arran
highest peak, Goat Fell. Apart from a small plantation at the far north east of the island, the north
end is covered in heather moors and granite outcrops. The south end of the island is more
‘lowland like’, with rolling heather moors, widespread forestry and the best agricultural land on
the island. The majority of the 5,045 population live in number if villages positioned on the coast
of the island.

The Isle of Arran

Although the population is small Arran has a diverse economy. A few big landowners, such as
the Forestry Commission, Dougarie Estate and Arran Estate, own much of the available land on
the island but farming is still wide spread and remains integral to Arran life. A number of
companies, such as Arran Aromatics, Arran Provisions and Arran Cheese Co., have used the
Arran label to great effect and have increased their market by selling their products throughout
Britain. A wide range of hotels, restaurants and guesthouses are available on Arran and provide
work for both locals and seasonal staff. The island is one of the top tourist destinations in
Scotland and is famed for its beauty and scenery. The economy of the island is heavily reliant on
tourism and for this reason it is crucial that Arran retains its uniqueness.

38
However, the island must move with the times, Arran’s carbon footprint is higher than that of a
similar population on the mainland. The daily lives of the local population have a far greater
impact on the environment than those of their mainland counterparts due to the ferry journey that
virtually all commodities must take. The isolation of the island and its associated transport costs
mean that the island should be aiming to be as self sufficient as possible in every facet of live.
This makes it the ideal location for this type of investigation, as it will potentially benefit the
most from the findings.

The Isle of Arran

Although the island is remarkably self-contained and can offer most services it lacks self-
sufficiency in key areas such as food production, electricity production and waste disposal.
Arran’s ‘on island’ electricity production is minimal, limited to a single micro hydro power
station and a few small private wind turbines. The remainder of Arran’s power requirements are
met by electricity imported from the mainland through underwater cables. The use of these six-
kilometre long cables increases costs due to increased maintenance needs. The situation is little
better in terms of waste disposal, six years ago the landfill site on Arran was closed after it was
decided that it had reached its capacity. Despite a lengthy search it was concluded that there were
no suitable sites on the island for a new landfill. Since this all waste from the island has been
transported off the island by ferry to mainland sites. This not only costs the council, and
therefore the taxpayer, it also results in an increase in Arran’s carbon footprint.

The island's unique blend of isolation, available biomasses and high transport cost makes the Isle
of Arran the ideal case study for this type of investigation.[3]

39
6.2.2 Malawi- Commercial Agriculture in Thyolo

Location and Overview

Malawi

Malawi is a landlocked country of 11.85 million hectares in Central Africa. It is bordered by

Zambia to the North West, Tanzania to the North East and Mozambique to the
South. Commercial agriculture is a major industry in Malawi, contributing considerably to
Malawi’s exports and, in turn, its foreign exchange earnings.

Commercial agriculture in Thyolo and Mulange has been chosen as a case study. Most
commercial agriculture estates in this area have several crops grown on a large scale and focus
on one of these crops as their strength. The land dedicated to producing these crops can reach
several thousand hectares per estate and is predominantly farmed extensively rather than
intensively. Therefore, the majority of the estates employ high numbers of labour, which in
many cases live on the estate and settle there with their families. In addition, many estates in
Malawi as a whole are in fairly rural areas, some distance from the larger town and cities.
Therefore, self sufficiency is a consideration that almost all long-standing estates hold important
to ensuring constant production. This means that many estates also have fully functional
garages, carpentry departments and engineering departments alongside factories to process the
crops. These factors mean that the commercial agriculture estates can demand high levels of
reliable energy to run effectively whilst also producing large amounts of agricultural, municipal

40
and human waste.
[2]

Energy Issues

Liwonde Barrage on Shire River

The Electricity Supply Corporation of Malawi (ESCOM) “remains the only company that
generates, transmits and distributes electricity on commercial terms in the country. Most of the
power is generated from a number of power stations along the Shire river. The Shire River is
Malawi’s largest river and runs from the outlet of Lake Malawi to where it joins the Zambezi
River in Mozambique to the South. “Nearly 95% of Malawi’s electricity supply is provided by
hydropower from a cascaded group of interconnected hydroelectric power plants located on the
middle part of Shire River and a mini hydro on the Wovwe River. Total installed capacity of
these hydropower plants is 282.5MW. The remaining 5% is harnessed from stand-by thermal
power plants bringing the “total present installed capacity for the ESCOM system, inclusive of
standby thermal plants about 299.65 MW..

Malawi should be commended for such a high percentage of total energy being harnessed from a
renewable resource. Unfortunately however, Malawi has a reputation for unreliable electricity
supplies. This can be largely attributed to problems with the hydropower plants on the Shire
River. According to ESCOM, “the hydropower plants on the Shire River....have operated
without major problems until in recent years when floating aquatic weeds/plants and debris being
transported in the river have caused severe operational problems and damage to intake structures.
Siltation of power plants reservoirs has also contributed immensely to the operational problems.

41
With such a high proportion of Malawi’s total electricity coming from hydropower, any
problems with the plants and/or river mean, often severe, electricity supply problems where load-
shedding is required. This hinders the agriculture industry as the estates require constant high
levels of electricity to operate continuosly. The problems can also be more frequent and serious
during the wet season from “October to April” when river flows, and consequently river load,
increase. In addition, this is a busy period of the year for the agriculture industry and soonly
adds to the problems. Consequently, most estates purchase very large, expensive diesel
generators as a back-up against this problem.

Waste Issues

Agricultural Waste

A third factor is the problem of waste disposal in these rural areas where municipal and human
waste disposal systems can be almost non-existent. Currently, most waste products are either
burned, buried, sold very cheaply or composted if possible. The only current disposal method
achieving any benefit to the estates is composting. It could therefore be suggested that a method
of recovering energy from waste products would be a sensible and welcome help. If some
energy could be recovered from agricultural, municipal and miscellaneous waste, several
benefits could be derived. These could be in the form of cost savings, a solution to waste
disposal, increased self-sufficiency, improved electricity reliability and potential improvements
in the standard of living of labourers if some of this energy was redirected for their benefit.
There may also be other benefits in the form of by-products from the energy recovery processes.

42
Summary

 Alternative fuels and energy sources are an issue of increasing importance - not only
among the scientific and engineering community, but also in economics and public
policy. Alternatives need to be compared on scientific and economic terms - which is not
done well in the media.
 Alternative fuels and energy sources provide an excellent opportunity to introducing a
variety of science topics, and increasing student interest in those topics. Science and
engineering fields are increasingly disciplinary - lessons on biodiesel can demonstrate
that clearly, by showing the overlapping of biology, chemistry, and physics in studying
this and other alternative fuels.
 Hydrogen which is an emerging biofuel, has shown tremendous potential in spite of
various risks involved in its transportation and storage.
 Bioethanol has become obsolete as a fuel but is still being considered as one of the best
biofuel.

43
References

[1] Licht FO. 2008 world fuel ethanol production. Renewable Fuels Assoc, http://
www.ethanolrfa.org/resource/facts/trade/; 2009.
[2] Cheng Y Sun , Cheng J. "Hydrolysis of lignocellulosic materials for ethanol production: a
review." Bioresour Technol 2002;83:1e11.
[3] Fan LT, Gharpuray MM, Lee Y-H. "Cellulose hydrolysis biotechnology monographs."
Berlin: Springer; 1987.
[4] Beguin P, Aubert J-P. "The biological degradation of cellulose. FEMS Microbiol Review
"1994;13:25e58.
[5] Stubbendieck JL, Hatch SL, Butterfield CH. North American range plants. 5th ed. Lincoln:
University of Nebraska Press; 1997.
[6] http://www.animalfrontiers.org/content/3/2/6.full.
[7] David H Mousdale "Introduction to biofuels "
[8] Jay J. Cheng , Govinda R. Timilsina , Status and barriers of advanced biofuel technologies: A
review
[9] For the UK Department for Transport by David Hart, Ausilio Bauen, Adam Chase,Jo Howes
Liquid biofuels and hydrogen from renewable resources

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