Session C8
138
Disclaimer — This paper partially fulfills a writing requirement for first year (freshman) engineering students at the
University of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is
based on publicly available information and may not be provide complete analyses of all relevant data. If this paper is used for
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THE FUTURE OF COMMERCIAL AVIONICS:
BIOMASS—SYNTHESIZED BY THE FISCHER-TROPSCH PROCESS—AS AN
ALTERNATIVE JET FUEL
Trevor Devine, [email protected] , 10:00 Mahboobin, Nicholas Trinovitch, [email protected], 1:00 Mena Lora
Abstract—Gasified biomass, subjected to the Fischer-Tropsch
process and converted into a blended BTL (Biomass-to-liquid)
fuel, is a potential new fuel substitute. In particular, it is a
promising replacement for jet fuel in commercial aircraft.
Biomass, with regards to energy, is municipal waste, crops,
and other biological materials. This substance is rich in
carbon and hydrogen, and can be sublimated through a
process called gasification. The synthetic gas (syngas) is
cleaned and converted in green kerosene in a Fischer-Tropsch
catalytic reactor. The newly created fuel is an alternative to
the traditional jet fuel found in most airplanes today, and
supports eco-friendliness and sustainability.
This paper will contain in-depth analyses of the FischerTropsch process, gasification, and the biofuel’s feasibility as
jet fuel. The process will be reviewed in both an economic and
scientific manner, to prove whether biomass fuel can be an
adequate replacement for fossil-fuel based avionic fuel.
Research done by organizations such as the Department of
Defense and Department of Energy, along with several
research groups, will be included as support. Examples of this
technology already in use will be included to prove the
commercial interest in BTL fuel. Graphs, formulae, and
statistics will all be used to better convey the significance of
the data.
Key Words- Biomass, BTL, Economic, Fischer-Tropsch,
Gasification, Sustainability
BIOMASS: A PROMISING ALTERNATIVE
TO COMMERCIAL JET-FUEL
The commercial aviation industry is one of the largest
sectors of the U.S. economy. Millions of people each year use
this essential service. Therefore, if a problem were to arise in
this market, the entire U.S. would feel its effects. We currently
have no such problem. However, this will not be the case for
the future. Commercial jets run on petroleum-based jet fuel, a
fossil fuel. As a nonrenewable resource, fossil fuels are far
from sustainable. Also, studies have found they are particularly
eco-destructive. Most industries have taken steps to research
and develop alternative sources of energy, such as solar farms,
University of Pittsburgh Swanson School of Engineering 1
3.3.2017
wind farms, and all-electric motors. Commercial airlines,
however, are yet to find a truly feasible back-up energy source.
A new and upcoming innovation, using a century old process,
has the potential to change this. Biomass, subjected to
gasification and the Fischer-Tropsch process, serves as a
viable jet fuel available for blending or complete substitution.
Albeit the expenses of the synthetization are currently high,
Biomass-to-Liquid (BTL) jet fuel promises increased
sustainability and ecofriendliness. This fuel beats out other
alternative energy sources, mainly due to its classification as a
“drop-in” fuel. There is no doubt that this new jet fuel has
immense potential. In fact, United Airlines and Fulcrum
Bioenergy have already invested in this technology. Biomassbased jet fuel has enough potential to keep the aviation
industry up and running through the near future, due to its
economic and environmental sustainability.
THE FISCHER-TROPSCH CYCLE AND
GASIFICATION- STEP BY STEP
Fischer-Tropsch Cycle and Gasification
The Fischer-Tropsch cycle converts biomass into a
usable fuel through a multiple step process. The first step is
gasification. Gasification is vital because it creates a gas
mixture of carbon monoxide, hydrogen, carbon dioxide,
nitrogen, and methane that is then re-arranged into a usable
fuel. To get these fuels, the process must begin with natural
biomass, which contains organic compounds of carbon,
hydrogen, and nitrogen (the specifics of these materials will be
discussed in the next section). Before gasification occurs,
however, the materials must be pre-treated to remove any extra
contaminants. This ensures that the gas produced is comprised
of mostly the compounds used in the later processes. While
there are multiple steps to pre-treatment, drying is the most
important. It was found that the dryer the biomass, the less
hydrogen was produced, making the actual Fischer-Tropsch
synthesis more effective [1].
Trevor Devine
Nicholas Trinovitch
There is a diverse assortment of gasifiers used in industry
today, including the updraft fixed bed gasifier, the fixed bed
gasifier, and entrained flow gasifier. Each gasification
technique differs slightly, but accomplish the same goal. In an
updraft gasifier, for example, the biomass goes through a few
stages, as depicted in Figure 1.
the raw-syngas. These need to be removed before the synthesis
can begin, as they will make the process less efficient and
could even drive it to a halt. For example, it is vital to remove
any O from the raw syngas, since the oxygen will oxidize the
catalysts, therefore slowing the reaction and decreasing the
amount of product produced.
Once the raw syngas is properly cleaned, the actual
Fischer-Tropsch Synthesis will begin. As defined by Jin Hu
and his colleges at the Department of Agricultural and
Biological Engineering at Mississippi State University, the
synthesis itself is a “set of catalytic processes for converting
synthetic gas … into liquid hydrocarbons” [1]. Most of the
reactors for this process are similar in design and functionality,
but the biggest difference between one reaction to another is
the catalyst used. There are four possible catalysts: Fe, Co, Ru,
and Ni [1]. The differences between the four major catalysts
will be described in greater detail in the following section.
.
The Materials Used in the Process
2
As mentioned above, the major starting material for the
Fischer-Tropsch cycle is biomass. Biomass is a subcategory of
municipal solid waste, or MSW for short. Municipal solid
waste includes many different waste products from wood
clippings to plastic bottles. Biomass, however, is specifically
organic materials like wood clippings and food waste. They
are comprised of carbon and hydrogen chains that become the
main building block of the bio-fuel produced from the
synthesis process. According to a chart found created by J. Hu,
Coconut Shell, Coconut Coir, Ground Nut Shell, Wheat Straw,
and Wood have the highest percent of carbon by weight [1].
This means that these materials will provide the most carbon
for the synthesis of the bio-fuel.
As mentioned in the previous section, the process itself is
dependent on the catalyst used. The process consumes a lot of
energy, so using a proper catalyst is vital to reduce the
activation energy required. The four most common catalysts
are Nickel (Ni), Iron (Fe), Ruthenium (Ru), and Cobalt (Co).
Nickel is very rarely used commercially, even though Ni is
almost just as active as the others, because it forms “too much
methane …[and] volatile carbonyls under high pressure” [1]
making it a danger to the process. Also, methane is too low of
a weight for a carbon chain making it useless for the synthesis
process, meaning material and energy is wasted [2].
Ruthenium, while similar to Cobalt in its activity, is a very rare
element. Consequentially, its cost is much higher than the rest.
Due to this, Cobalt and Iron are the most common catalysts.
The decision of which catalyst will be used is dependent on the
starting materials in the cycle. If a company were to use coal,
Iron would be the catalyst of choice due to its inexpensive price
and its “high water-gas-shift” activity [3]. In other words, it is
better at capturing the synthetic gas if the syngas has a low
hydrogen/carbon monoxide ratio, like in the coal gasification
process. Cobalt wouldn’t be used for coal gasification because
of its “higher sensitivity to sulfur” [3]. Therefore, Cobalt is
FIGURE 1 [2]
Basic Diagram of an updraft gasifier
The first step is the drying stage. By drying the material
any excess water is removed, allowing more of the material to
be converted into syngas. The next step is the devolatilization.
Devolatilization is the removal of volatile substances from the
solid by grinding the solid down and separating it by parts. The
final step occurs when the biomass reaches the bottom and
combusts with the help of a gasifying agent to produce the
syngas and any waste products [1].
Gasification, compared to the other processes of
converting biomass to the desired product, is the most
efficient. A generalized version of the chemical reaction is
depicted below:
Biomass + O2 (or H2O)  CO, CO2, H2O, H2, CH4
+ other CHs + tar + char + ash
Gasification can have an efficiency of 98%-99% in
converting the carbon into a usable form [1]. In terms of the
reaction, CH4 and other CHs are produced the most, while the
production of char and ash, waste products, is minimized. CH4
and CHs are the main ingredients to fully synthesizing the
biomass jet fuel. Additionally, gasification also produces less
pollutants in the form of CO and CO2, making it the best
method for converting biomass into its component parts.
No matter the amount of cleaning and pretreatment done on
the starting materials, there is almost always still impurities in
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Nicholas Trinovitch
most often used in synthesis of natural gas or biomass because
of their low sulfur content.
and gasification processes also produce excess gas that can be
used to either generate power or refine the longer CH chains,
(the wax depicted in Figure 2), and reform them into a usable
liquid fuel.
Products of the Fischer-Tropsch Cycle
As described above, the temperature, pressure, and feed
composition play an influential role in determining what is
produced from the cycle. While the product composition may
vary from cycle to cycle, the four general products are light
oils, heavy oils, carbon chains of five and above, and carbon
of one to four carbons in length [4]. The larger carbon chains
are what compose the finished bio-fuel, but the shorter carbon
chains serve a much different purpose. These short chains can
either be used to refine the larger chains, or they can be utilized
to make electricity. If these carbon chains were to be redirected into a turbine, because of their high temperature and
velocity following the gasification process, they will be able to
generate electricity. This is important because this energy can
be used to push the final synthesis process along. By
combining the cycles parts into a single loop, it can help make
a plant “energetically self-sufficient” [5]. There was a study
that found that the net energy of the system itself is a positive
3831 MJ/FU, ‘FU’ being a fixture unit representing one cubic
foot of water [5]. This self-sufficiency is important for the
future of the product, since it can reduce overall costs.
Even though the Fischer-Tropsch fuels are produced
from biomass comprised of waste, they can create a fuel that
rivals traditional jet fuel. Fischer-Tropsch fuel not only has a
high cetane number, meaning it has a bigger energy density,
ignition, and thrust, but it also has a low aromatic content. This
means that when it is combusted, it will produce less CO and
NO , both of which are greenhouse gases that contribute to
global warming [6].
FISCHER-TROPSCH CYCLE: BENEFITS
AND CONSEQUENCES
The Fischer-Tropsch Cycle: The Economic Assessment
Before a discussion of what effect a Fischer-Tropsch fuel
will have on the economy, its economic feasibility needs to be
considered. The cycle itself involves multiple steps as
mentioned above, similarly to its kerosene counterpart. The
question, then, is whether the Fischer-Tropsch cycle can even
compete with the current jet fuel cost wise.
Two professors at the Lappeenranta University of
Technology created an in-depth study of the economic
possibilities of bio-fuel. Figure 3 contains the costs that a
company would face if they were to convert a plant to be able
to produce Fischer-Tropsch fuel.
Costs:
Purchasing Equipment:
Physical Plant Costs:
Investment Costs:
Total Fixed Operating Costs:
Total Variable Operating Costs
Total:
Dollars ($):
$1,196,350.40
$3,225,813.00
$5,233,935.00
$751,977.60
$7,477.05
$10,575,753.15
Figure 3 [4]
A table displaying average costs for various aspects
of producing Bio-Fuel
2
x
The total investment cost, according to the study at
Lappeenranta, can be split up into two major components:
equipment cost, and operation cost. The equipment cost is the
price tag associated with the initial purchase of all the
necessary machines. It is estimated that the total equipment fee
for a single plant would fall around $1,196,350.40.
Considering the design cost of the plant along with the
construction labor cost, the total investment rises to about
$5,233,935 [4]. This high initial price is what will make it
difficult for a lot of companies to switch from fossil jet fuel to
a new fuel that requires them to replace all their equipment.
On top of the equipment cost, there is also the total
operating cost. The first factor of operation cost is the fixed
cost. The fixed cost includes static figures like worker salary,
labor costs like health insurance, maintenance costs, and plant
overhead costs. It is estimated that this will total to around
$751,977.6 [4]. The second component of operation cost is the
variable costs. The cost of electricity, air, water, and starting
materials like wood, coal, or natural gas all fall under variable
costs and total about $7,477.05 for a single cycle [4]. If it’s
sold at a price of around $619/ton, it is estimated it will only
FIGURE 2 [2]
Outline of the Fischer-Tropsch Synthesis
Figure 2 depicts the general overview of the FischerTropsch cycle. In this case coal is being used as the fuel for
gasification, but any biomass material can be substituted
above. As a summary of what was discussed above, the process
begins with a fuel undergoing gasification, which produces
raw syngas. This syngas is then cleaned and undergoes the
Fischer-Tropsch synthesis. From here the final fuel is
produced and sent to be stored and transported. The synthesis
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Nicholas Trinovitch
take a year before the initial investment is payed back [4]. This
shows that an investment in BTL fuel is economically sound.
The biggest part of the cost of the production of the
Fischer-Tropsch fuel is not the numbers themselves, but how
they compare to the current market of jet fuel. Per a fuel price
analysis by IATA, the current jet fuel price falls around
$528.3/ton [7]. Because of this there isn’t too large of a market
for biofuel in today’s economy. According to a journal article
in Global Change Biology, which is a monthly scientific
journal concerning conservation biology and environmental
sciences, “the cost of bio jet fuel … could be competitive with
fossil jet fuel by 2035” [8]. Because of the rising price of jet
fuel, caused by the diminishing supply of fossil fuels, the price
will eventually rise to that of biofuel. Bio fuel could be
competitive now if the carbon price were to rise, but it is
predicted that by 2035, bio fuel will be competitive with jet
fuel, regardless of the cost of carbon at the time. [8].
Consequentially, investments should be made now, so that the
transition to BTL fuel can occur smoothly by around 2035.
The final issue in implementing biomass-based jet fuel is
the approval process. A new jet fuel must first go through
rigorous testing before it can be approved for commercial use.
Pure Fischer-Tropsch Bio fuel is still being improved and
tested so that it can stand on its own. Currently, however, there
have been multiple airline companies that have performed
flights using fuels that are a blend of the newer bio fuel and the
traditional jet fuel. The higher end of the mix seen has been
50% biomass-based jet fuel [10]. Because it has not been used
very often, most people are not very trusting of the new fuel.
Therefore, it's slowly being integrated through mixtures until a
foothold is found and be used on a full commercial scale.
Sustainability of Fischer-Tropsch Jet Fuel
Sustainability is the quintessential advantage of biomassbased jet fuels over their petroleum-based counterparts.
Sustainability is defined by UCLA to be “development that
meets the needs of the present without compromising the
ability of future generations to meet their own needs” [10].
Currently, the U.S. commercial aviation industry is not
meeting this standard, due to the use of non-renewable jet fuel.
Within the next 50 years, the availability of fossil fuels will
drop substantially as demand for them continues to grow.
Supply will not match demand, and there will be a shortage
created, hurting the global economy for generations to come.
Consequentially, provided three key requirements are met,
biomass-based jet fuel has remarkable potential to replace
petroleum jet fuel.
First, for proper sustainability to occur, the land used to
grow the crop-based feedstock must be managed
conservatively, and with carful regard for the environment. As
SkyNRG, a sustainable biofuel company, states, “In order to
achieve the high biomass potential deployment levels, …land
must be properly managed and agricultural and forestry yields
must increase substantially.” [12]. Proper management of land
includes not overusing the soil, banning slash-and-burn
farming, and making use of all available land space. U.S.
farming techniques currently employ each of these, but many
third-world countries do not. Therefore, implementation
should begin in the U.S. and other developed countries, until
proper farming is taken up by impoverished countries. As long
as effective land management is practiced, BTL fuels are
adequately sustainable to fuel the commercial aviation
industry. Without these techniques, however, BTL fuels can be
even more unsustainable than fossil fuels, as they carry the risk
of conflict with food supplies and biodiversity.
The second aspect of a sustainable biomass jet fuel is a
second generation crops feedstock. Second generation crops,
as explained before, consist of Lignocellulosic materials,
agricultural residues, and cultivated grasses and trees. Each of
these feedstocks share one common attribute—they are not
designed for human consumption. This essential trait prevents
a conflict of interests with mankind’s need for food. Due to
this, the food and biofuel industry can operate side by side,
without competition between the two. Furthermore, according
What Problems are Stopping its Implementation
While this bio-fuel may be a possibly great alternative to
the modern jet fuel, due to its low sulfur content and high
density of energy, there are multiple reasons why it is still not
being fully implemented. One of the most challenging to solve
is also one of its benefits. Depending on the catalyst and
materials used, most Fischer-Tropsch fuels have a low sulfur
content [3]. The fact that there is little sulfur in the fuel means
that there is no production of sulfur dioxide upon combustion,
making the fuel better for the environment. Sulfur, however,
acts as a lubricant for many other types of jet fuel. For this fuel
to be usable then, a synthetic lubricant would have to be added
after production. By adding a synthetic lubricant, the fuel can
lose its energy density due to this new material, or, depending
on the lubricant added, it can produce harmful chemicals when
burned.
Furthermore, another major issue is the lack of a market.
As mentioned above, the fuel is currently more expensive than
the modern jet fuel. This alone is enough to push a company
away from trying to integrate this fuel into their company. To
make matters worse, before the fuel will even reach these
commercial plane companies, the plants making it first must
buy all new equipment and completely change their systems.
This high initial price is discouraging most companies from
even attempting to produce the fuel, meaning less supply will
reach the market.
Also, the success or failure of this fuel in the market is
too dependent of the cost of regular jet fuel. It’s dangerous for
a company to put their faith in something as new and as
unreliable at bio-fuel when the price of oil can change at any
time, causing fluctuation in the price of modern jet fuel [9]. If,
for example, the price of jet fuel was to suddenly plummet due
to a drop in the price of oil, most companies would switch from
biofuel to jet fuel, eliminating the biomass fuel market.
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Nicholas Trinovitch
to the UK Biofuel.org site, “second generation feedstock
should grow on …land that cannot be used for “arable” crops,
meaning it cannot be used to effectively grow food.” [13].
Using normally nonarable land ensures that the feedstock will
not take away from the food supply, which would remove
biomass from the alternative fuel list.
The last factor in a sustainable biomass fuel deals with
the diversity of the bio stock. As mentioned previously,
biomass-based jet fuel can be produced from a wide variety of
carbon-based materials. Depicted in table 2 is the potential
feedstock, based on geographical location.
Type of
Biomass
Forest residues
Agricultural
Residues
Organic Waste
streams
Components







Primary forest fuels
Wood
Whole stems
Rice Husk
Bagasse
Straw streams
Corn Stover



Demolition wood
MSW
Green wastes
luxury, and, consequently, is not sustainable. Biomass’ variety
and widespread availability is essential to its potential success
as a fuel source.
Biomass-based jet fuel also offers strong economic
sustainability, another result of the diversity of its feedstock.
Unlike petroleum-based jet fuel, BTL fuel prices will not
drastically change if one type of biomass is somehow made
unavailable; there are several other substitutes that can take its
place. Such market stability is particularly valuable to
commercial airlines, since it provides a form of economic
safety. This economic safety extends to future generations, as
the commercial aviation industry will continue to thrive, even
if draughts and disasters affect one of the feedstocks. Prices
will remain low, and air travel will remain commercialized,
available to all. Diversity in bio stock, along with proper land
use and second generation crops, will allow biomass-based
fuel to surpass fossil fuels in sustainability, with respect to the
commercial aviation industry. This sustainability, as will be
discussed, complements biomass’ other key advantage—
ecofriendliness.
Regions


Canada
N. Asia



S. USA
E. Europe
S. Asia




N.E. USA
W. Europe
India
E. Asia
Ecofriendliness
One of the most crucial factors in an alternative fuel’s
feasibility is the potential benefit—or harm—it brings to the
environment. As a form of sustainability, ecofriendliness is
another essential characteristic of biomass-based jet fuel.
Compared to other fuel sources, BTL fuel is not perfectly
clean. However, it has two distinct improvements over
traditional kerosene jet fuel. Most notably, biomass-based jet
fuel has an eco-friendlier carbon dioxide life cycle. The
National Academy of Science analyzed the life cycle of BTL
fuel, taking into account, “all emissions associated with
producing the final fuel from its initial form, as well as aircraft
emissions,” and determined that this biofuel could reduce the
life-cycle emissions, in comparison to petroleum-based jet fuel
[15]. This scientific article further explained that “biomassbased hydrocarbons …[absorb]… CO2 from the atmosphere
when they …[grow]… and the CO2 emitted during fuel
combustion is equal to that absorbed during its growth” [15].
The net effect, then, on the environment due to carbon dioxide
emissions is essentially zero. Fossil fuels, on the other hand,
have a positive emission status, as they release CO2 previously
kept from the atmosphere. Carbon dioxide emission has been
proven to negatively harm the environment, and the
commercial airline industry is one of the largest CO2 emitters
in the country. Consequently, with an improvement in the lifecycle of carbon dioxide through a switch to biomass-based jet
fuel, less harm will be done to the environment by commercial
planes.
BTL jet fuel has another benefit that allows it to surpass
kerosene jet fuel, in terms of ecofriendliness. A biomass jet
fuel has much lower emissions of the oxides of Sulphur (SOx)
and other particulate matter. Specifically, a Purdue research
study found that BTL jet fuel has a 100% decrease in SOx
emissions, and releases 50%-90% less particulate matter [9].
Managed grass lands
Commercial wood
 S. America
plantations
 Africa
Cultivated
 Energy grasses
 Indonesia
biomass
 Agroforestry systems
 Australia
 Saline and semi-arid
conditions
FIGURE 4 [14]
The regions and components of several types of Biomass


As shown, at least one major type of biomass is located
on every inhabited continent. For example, Canada and
Northern Asia both have ample supplies of whole stems, in the
form of Mountain pine wood and underutilized forest
resources, respectively. South America and Africa have ample
grasslands, providing a sustainable, regionally sourced
biomass [14]. Densely populated regions and cities, mainly in
Western Europe, Northeastern USA, and Eastern Asia
produced an enormous load of MSW [14]. MSW itself is very
sustainable, since garbage is constantly produced at a high rate.
Finally, in regions with large farms and plantations, biomass
feedstock consists of rice husks, straw streams, and corn
stover, which are all unused waste products of agriculture [14].
The feedstock for biomass is incredibly diverse and widely
available. This characteristic is what truly makes biomass a
sustainable fuel source. The current generation can develop
and grow, using biomass as fuel, without compromising the
needs of the future generations. Even if one of the feedstocks
becomes unusable, there are ample substitutes to create the
same exact fuel. Petroleum-based jet fuel does not have this
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Nicholas Trinovitch
SOx is a known polluter that taints the quality of water and
soil, due to acid deposition [16]. By reducing the amount of
SOx produced, commercial airlines can greatly help global
ecosystems maintain a healthy balance of pH. Biomass jet fuel
offers a viable option for airlines to drastically lower Sulphur
production on a large scale. Continued use of petroleum-based
will only exacerbate the problems associated with SOx
production, and lower the general condition of the
environment. Biomass has obvious benefits to the
environment, notably a better carbon life-cycle, and lowered
SOx production, which can be best utilized in the commercial
aviation industry as a replacement to eco-destructive
petroleum jet fuel.
they want to use on a flight-by-flight basis. For example, an
airline may decide to use a biomass-petroleum jet fuel mixture
for domestic flights, and continue using traditional jet fuel for
long international flights. Such fuel flexibility has the potential
to improve the entire aviation industry as prices will be less
likely to fluctuate in response to a price change of one fuel.
Moreover, if a more efficient drop-in biofuel is produced, BTL
jet fuel will not obstruct its implementation. The biomass fuel
could simply be removed from production, and replaced with
the better jet fuel, without any added cost. BTL jet fuel, since
it is a drop-in fuel, is much more advantageous in the
commercial aviation industry than other alternative energy
sources.
AN ALTERNATIVE JET FUEL FOR
COMMERCIAL AVIATION- THE IDEAL
APPLICATION
Why the Commercial Aviation Sector?
Biomass-based fuel is certainly a viable alternative to
fossil fuels in several different applications. However, BTL
fuel would be most effectively utilized as a jet fuel, especially
in the commercial aviation industry. Traditional jet fuel was
originally favored for its somewhat unique properties, as
opposed to land transportation fuels, such as gasoline or diesel.
Per the National Academy of Science, jet fuel specifically has
a “high energy per unit mass, high energy per unit volume,
stability, nonvolitity, …and low toxicity” [4]. These
characteristics allow commercial air travel to be both safe and
effective, which gave rise to the booming industry today.
Consequentially, an alternative jet fuel must share these
stringent characteristics, and not many fuel sources do.
Biomass-based jet fuel, however, has only a slightly smaller
energy density, which is one reason why it has so much
potential. As research conducted by a Purdue team found,
biomass jet fuel ranks first and second in energy per unit
volume and per unit weight, respectively, as compared to
ethanol and hydrogen based fuels [9]. This explains why BTL
fuel outpaces its competition, at least in regards to jet fuel.
Such a high-energy density means that biomass fuel can be
mixed in with traditional jet fuel, without a major reduction in
energy output. This is essential in making a smooth transition
away from petroleum-based jet fuels, as the industry will be
affected less.
Furthermore, BTL fuel is most applicable to commercial
aviation due to harsh competition in other sectors. For
example, the consumer car market is currently being
dominated by fully-electric cars. With Tesla’s growing
popularity, the electric car market is at an all-time high. Almost
all car manufacturers have an electric car as part of their fleet.
Therefore, any introduction of biomass fuel as an energy
source for cars could be rejected, since consumers would tend
to prefer their counterpart electric cars. Just like with fossil
fuels, people tend to only trust technology to which they have
constant exposure. Electric cars have recently made the jump
into consumer trust, so they pose a serious threat to a potential
BTL fueled car. Thus, a BTL fuel must enter an industry where
no other alternative fuels have taken a dominant role, unlike
most of the land-based transportation today. The commercial
BTL Jet Fuel vs Other Energy Sources
The market for alternative fuels consists of a wide and
diverse set of clean biofuels, fully-electric motors, and other
promising innovations. Each fuel has its strengths and
weaknesses, based on how and where it is used. In regard to
the commercial aviation industry, biomass-based jet fuel is
superior, as compared to other power sources such as ethanol,
electricity, and hydrogen. This superiority arises from several
differences between these energy sources. Foremost of all,
however, is BTL jet fuels’ classification as a “drop-in” fuel.
According to the FAA’s website, “drop-in fuels mimic the
chemistry of petroleum jet fuel, and can be used in today’s
aircraft and engines without modification and provide the same
level of performance and safety as today’s petroleum-derived
jet fuel.” [17]. As a drop-in fuel, Biomass jet fuel can be
substituted directly in for traditional jet fuel, with little to no
consequences. Additionally, BTL fuel can be mixed with
kerosene jet fuel to produce a cleaner-burning jet fuel with
similar characteristics, in terms of energy produced. The dropin nature of biomass jet fuel is valuable to commercial aviation
companies, as they can reduce research and development costs
other fuels require. Specifically, per a Purdue analysis on BTL
jet fuel, planes that run on either hydrogen or ethanol must be
redesigned entirely, along with their engines [9]. These fuels
are more appropriate for land-based transportation, which
already have the specific engines being designed.
Furthermore, diversity is needed in fuel sources, across
all industries and sectors. A drop-in fuel only broadens this
diversity. As Dr. Andre Faaij of Utrecht University explains,
companies making aircraft will not restrict their technology to
using only one type of fuel or operation. [12] Companies want
to make as much money as possible, so they always try and
keep a wide range of options available to them. Employing a
drop-in fuel, then, gives a commercial airline much more
security than other energy sources that change the airline
technology itself. An airline company can choose which fuel
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Nicholas Trinovitch
airline sector absolutely fits this requirement. No other
alternative fuel has dominated the industry like electric cars
have for transportation. BTL jet fuel, then, has less competition
which could drive it out of usage. With few choices for
alternative fuels, the commercial aviation is the ideal
application of biomass-based jet fuel.
Fischer-Tropsch cycle to synthesize the energy dense bio jet
fuel. The finished product is resold to commercial airlines
alongside petroleum jet fuel, to be used in a mixture, or as a
stand-alone fuel. The future dynamic between traditional jet
fuel and biomass jet fuel would be akin to the diesel/gasoline
relationship seen in the transportation sector. They are
different fuels, yet share the industry almost evenly.
Eventually, BTL and petroleum jet fuels would become perfect
substitutes for one another, benefiting the industry and the
environment, due to biomass’ sustainability.
While no company has truly introduced biomass jet fuel,
two airline companies have shown a strong interest in biofuels,
including biomass-based jet fuels. One of them, United, has
already teamed with a biofuel company to fuel their jets in Los
Angeles Airport with a 30/70 blend ratio of biomass jet fuel,
according to their corporate website [19]. United’s push for
ecofriendly fuel shows airline companies’ desire to reduce
fossil fuel consumption. Their choice in biomass-based jet fuel
also proves that companies take BTL fuel seriously, and view
it as a potential replacement for traditional jet fuel. Since
United has already laid the groundwork, other airlines may
soon start to utilize BTL jet fuel in their own aircraft,
increasing the demand for this fuel. This then leads to more
Fischer-Tropsch plants being created, and an expansion in the
entire market for biomass-based jet fuel. Symbiotic
relationships will develop between manufacturers and airline
companies, creating jobs and growing the economy. For
example, Fulcrum Bioenergy has also signed a deal with
Cathay Pacific Airways for a 375-million-gallon deal [18].
Such cooperation between companies displays the interest
both manufactures and airlines have in this fuel, and reinforce
its viability as an alternative jet fuel.
FISCHER-TROPSCH PLANTS AND
BIOMASS JET FUEL IN USE TODAY
Current Fischer-Tropsch Plants
An alternative fuel can only be introduced in an industry
if companies show an interest in it. Governments and scientists
may research and discover a new source of energy, but
companies must be the ones to invest in and use this
technology. For biomass-based jet fuel, there must be a
corporate interest on two levels. Both the fuel itself and the
Fischer-Tropsch cycle must be commercialized together,
otherwise a BTL jet fuel could never be produced. Due to this,
a manufacturer’s interest in creating a Fischer-Tropsch fuel
plant is essential to introducing biomass-based jet fuel to
airline companies. Luckily, several companies have already
invested in a Fischer-Tropsch plant to convert biomass into jet
fuels. One such company, Fulcrum Bioenergy, is paving the
way to creating a multimillion dollar plant in the United States.
According to the European Biofuels Technology Platform,
Fulcrum has given a $200m contract to Abengoa to create a
facility to synthesize bio jet fuel by using gasification and the
Fischer-Tropsch cycle to convert municipal solid waste into
syngas [18]. Fulcrum Bioenergy has displayed a committed
interest in producing bio jet fuel, which proves there is a
market and desire for such a technology. If this plant becomes
an economic success, Fulcrum may build even more plants to
expand their investment in biomass jet fuel. This will drive
other companies to enter the market, potentially creating a
booming industry, which would lower the economic impact of
a transition to BTL jet fuel. Companies’ interest in creating
Fischer-Tropsch plants is a strong indicator of biomass-based
jet fuel’s potential to become the dominant alternative fuel in
the commercial airline industry.
CONCLUSION: BIOMASS-BASED JET FUEL
IS THE FUTURE OF COMMERCIAL
AIRLINES
An industry based solely on a dwindling resource is
doomed to fail eventually. The commercial airline sector,
relying on petroleum-based jet fuel, needs its own alternative
fuel source to maintain its economic success. Biomass-based
jet fuel, created through the Fischer-Tropsch process, offers
such an option. Although it initially is much more expensive
than traditional jet fuel, it offers a better hope for future
stability. This stability is a result of the biofuel’s high
sustainability, along with its eco-friendly nature. Furthermore,
as a drop in fuel, BTL jet fuel can be put into any commercial
plane flying today, with few consequences. Such flexibility in
fuel provides safety for airline companies, and profits in the
future. Fossil fuels are known to be problematic for the
environment, and are bound to run out in the future.
Consequently, investments in biomass jet fuel must be made
soon, to allow adequate time for the technology to develop
further, and enter the commercial market in the coming years.
BTL fuel is far from perfect, but it offers an alternative to
Progressive Airlines- Beginning the Fuel Switch Now
Fischer-Tropsch plant development is only half of the
two steps necessary for BTL jet fuel to be produced
commercially. Airlines themselves must show a desire to use
these fuels in their aircraft, otherwise the fuel would never sell.
Currently, there is no company who has fully switched over to
biomass-based jet fuel, but this does not limit its potential.
Hypothetically, biomass and petroleum jet fuels can be used
interchangeably in the future. The process could begin in New
York city at a local municipal waste center, where garbage is
bought by a company with Fischer-Tropsch facilities. This
garbage would be cleaned and gasified, then subjected to the
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Nicholas Trinovitch
traditional jet fuel, something currently lacking. Petroleum
reserves will eventually run out, and when they do, airlines
need a backup or else the entire industry may crash. Biomassbased jet fuel may only one possible alternative, but it
absolutely shows the most promise for sustaining the future of
commercial aviation.
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ACKNOWLEDGEMENTS
We would like to thank our co-chair Emelyn Haft for
helping us format our paper and choose how to present our
information. Also we would like to thank Josh Zelesnick for
providing helpful insight to help us make our paper the best it
can be. Without their help, this paper may not have been
completed to the degree it currently is.
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