2. “As the aviation industry plans for future
growth, sustainability must be considered
every step of the way. Advances in aircraft
technology and sustainable biofuels will
position our industry to reduce emissions while
maintaining a competitive advantage.”
– Rosemarie S. Andolino, Chicago Department of
Aviation
3. Introduction
• The use of sustainable aviation fuels and other
potential alternative energy sources (such as
electricity, hydrogen, solar and more) will be
necessary to secure supply and further reduce
aviation’s environmental footprint in the long
term.
• This will allow the extensive introduction of
regionally-sourced renewable energy close to
airports, feeding both aircraft and
infrastructure requirements sustainably.
4. The Need of Change
Global warming is observed and
largely caused by human drivers
•Commercial air traffic is increasing continuously over several
decades (between 1995 and 2005 an increase on average of
5.2 % per year)
•Increased Growth rates of Greenhouse gas concentrations
(Carbon Dioxide, Methane, Nitrous Oxide) during the last 50
years.
•Carbon Dioxide (CO2) increases caused mainly by burning
fossil fuels.
•Contribution of air traffic to CO2-emissions: world wide =
2%
5. What Should be the Change
REDUCING FOSSIL FUEL DEPENDENCE
• Like most types of transport, the aviation
industry depends on fossil fuels. However, fuel
supplies are becoming uncertain, more
expensive and can cause environmental
harm.
• In the last 40 years, aircraft fuel consumption
and emissions have been reduced by 75 per
cent as the result of technological advances
and positive steps across the aviation sector.
6. What Should be the Change
EFFICIENT FUEL USE
• In order to meet the industry’s eco-efficiency goals,
aircraft manufacturers must ensure every drop of
fuel is used efficiently and develop new
ecologically-sound alternatives.
• Airlines already are seeing the benefits with
jetliners like the double-decker A380, which only
produces about 75 grams of CO2 per passenger
kilometre – well below the current and anticipated
future international limits . However there is always
room for improvement.
8. Alternatives of energy sources
• Hydrogen as a fuel
• Fuel cells
• Solar power
• Alternative Fuel (Biofuel)
9. • Significant improvements in aircraft fuel efficiency are
being achied (1-2% per year).
• However annual air traffic growth (~5%) is leading to
an increase in CO2 emissions due to air transportation.
• This, along with aviation’s strong dependency on fossil
fuels, is driving research towards development on non-
carbon based fuel technologies.
• Within the fuel cell and hydrogen technology sector,
aircraft manufacturers are investigating the potential of
PEM FC and SOFC systems to power light aircraft or as
APUs on-board commercial aircraft.
10. Hydrogen as a Fuel
• Hydrogen as a fuel is too bulky.
• Also it is not available in pure form on earth.
• So, a lot of energy will be required to produce
it in the pure form.
• It is a good option to be thought of but not in
the near future.
11. Types of Fuel Cells
The commonly used
fuel cells are:-
•PEM FC(poly
electrolyte membrane)
•SOFC(solid oxide Fuel
cell)
12. How fuel cells work
•Hydrogen and oxygen from air
•Produces Water and Inert gases
And ELECTRICITY
Cold
Combustion
Chemical
reaction
13. Use of Fuel Cells in Aviation
• Till today it is not possible to drive a passenger
aircraft only with the help of fuel cell but
surely we can extract the use of fuel cell in
small light weight aircrafts and also to power
some systems in civil passenger aircrafts.
14. Use of Fuel cell in small aircrafts
• The first ever flight of a manned aircraft
powered by hydrogen fuel cells in February
2008 was both a milestone in flight history
and an indicator of the advantages and
possible limitations of fuel cells in airborne
applications.
15. Multi Functional Fuel Cell System
• Power provision (APU, emergency power)
• Emission free ground operation
• Autonomous Taxiing
• Maintenance bus supply
• Cargo reloading
• Electrical Main Engine Start
• - EECS supply on ground
• - Water generation (potable water
• and water for toilets)
• Heat generation (icing prevention,
• hot water generation)
• Explosion and Fire Prevention and
• Suppression (inerting of tanks,
• cargo and e-bay compartment)
16. Use in Big airplanes
• They are used to generate the
electrical power needed to supply
the systems for aircraft control and
cabin comfort, and they power the
hydraulic and pneumatic systems
that operate the aircraft. Fuel cells
can generate electrical power much
more efficiently than conventional
engine-driven generators while
silently delivering emissions
reductions.
17. • One of the greatest advantage of using a fuel
cell is that the water which is produced after
the reaction can be used in galleys and
lavatories of the aircraft.
• That reduces the water to be carried during
the initial takeoff.
18. Barriers and Drivers for Fuel Cells
Drivers Barriers
Reduce emissions Technology needs to be proven
Quiet operation Hydrogen Infrastucture
Low infra red, good for surveillence in
UAVs
High Initial cost
Improved fuel efficiency
Weight reduction
By products (Water and heat) produced
can be used efficiently
The aircraft industry will not be an early adopter of fuel cell technology. However, given the
interest in the technology displayed by two of the world’s major aircraft manufacturers, it is
likely that fuel cells will appear in aircraft in the future. The most likely applications are hybrid
fuel cell APU systems for commercial aircraft, with products appearing around 2020; and
specialised military applications for surveillance.
19. Solar Energy
• If solar power is a highly-promising renewable
energy source for Earth-based applications, its
use on aircraft has been limited because of
the way such power is created and
stored. While solar energy may be able to
help a small aircraft fly, it is unlikely to be a
practical solution for enabling larger,
commercial airliners into the sky.
20. How much power can be generated
It has been seen that on a 747 plane, we can apply around 12,000
solar cells.That’s about 200 square meters of solar cells.Power from
sun 250 Watts/square meter.
Therfore total power=250 Watts/square meter × 200 square meters
= 50,000 Watts.
21. • The best commercially available solar cells are
about 20% efficient at capturing solar power, and
then there are further losses in the batteries and
the electric motors, total efficiency=12%.
• Power obtained=6000 watt
• A 747 has a glide ratio of around 12.
• From the power formula a plane having wingspan
as same as a 747 and having a avg speed of say
12metres/sec should weigh only 6 tons to fly!!!
with solar power...
22. Future of Solar power
• The technology might take a
giant leap forward with
future advances but today,
even if an entire aircraft was
covered with the most
efficient solar panels
available, this still would not
be enough to propel it.
23. Near Future of Solar Power
• For the more immediate future, solar power
could provide electricity aboard airliners once
they reach cruise altitude, or possibly help
with ground operations at airports.
24. Alternative Fuels
• The industry is exploring reliable alternatives to conventional jet fuel that
are sustainable and have a smaller carbon footprint
• Main requirements for sustainable alternative jet fuels:
– Should be able to mix with conventional jet fuel, sholud use the same supply
infrastructure and not require adaptation of aircraft or engines (drop-in fuel)
– Meet the same specifications as conventional jet fuel, in particular resistance
to cold (Jet A: -40˚C, Jet A-1: -47˚C), and high energy content (min 42.8 MJ/kg)
– Meet sustainability criteria such as lifecycle carbon reductions, limited fresh
water requirements, no competition with food production and no
deforestation
– Automotive bioethanol and biodiesel are not suitable
• Sustainable aviation bio fuels (“bio jet fuels”) are one of the most
promising solutions to meet the industry’s ambitious carbon emissions
reduction goals
• Sustainable biojet fuels allow airlines to reduce their carbon footprint,
ease their dependence on fossil fuels, and offset the risks associated with
the high volatility of oil and fuel prices
25. Sustainable Sources of Biomass
• Bio fuels should only be made from sustainable, non-food biomass sources.
Some examples include:
– Camelina is an energy crop that grows in rotation with wheat and other cereal
crops
– Halophytes thrive in salty regions where little else grows
– Jatropha can be grown on degraded lands and is resistant to drought
– Switch grass grows quickly, needs little water and produces a high yield of
biomass
– Used cooking oil can be easily collected and recycled
– Agricultural and forestry by-products yield valuable biomass without requiring
dedicated land
– Municipal waste contains biomass and can be diverted from landfills
– Algae are simple, photosynthetic organisms
• Can be grown in polluted or salt water
• Can produce up to 250 times more oil per unit area than soybeans
• Lifecycle greenhouse gas emissions from biofuels can be up to 80% lower
than traditional fossil jet fuel emissions
28. The Process
• Photosynthesis is a biochemical process, during
which algae absorbs light energy from sunlight and
carbon dioxide from the atmosphere or a industrial
(e.g. stackgas) source; utilizes water and critical
nutrients (nitrogen, phosphorous and other key
nutrients); and undergoes multiple step light and
dark phase reactions to biologically produce
primarily lipids (fats and oils), carbohydrates
(sugars) and proteins subsequently generating
oxygen off-gas.
29. • Algae production basically includes the sourcing
of carbon dioxide, water, nutrients and light
energy to the photosynthesis system for
conversion to algae of a specific composition.
• Carbon Dioxide Source – There are a number of
potential carbon dioxide stackgas sources with
high CO2 concentrations preferable for algae
production, including power plants and energy
intensive manufacturing facilities.
• Water Supply – Water provides the critical
hydrogen source for photosynthesis. Various
algae species thrive in fresh water and/or high
salinity water environments. Certain wastewater
streams, containing high levels of nutrients, may
also be effectively utilized for algae production.
30. • Nutrient Source – The primary nutrients required for
photosynthesis include nitrogen and phosphorous,
sourced from conventional N/P fertilizers.
• Light Energy – Sunlight provides the main energy source
for conversion of CO2 and water into algae, generally
70% to 85% of the total energy requirements. Only the
visible light portion of sunlight is useful for algae
production and more specifically certain wavelengths are
more efficiently absorbed.
• Algae Composition – The composition of algae product is
highly dependent on the specific species utilized and the
photo-synthesis operating conditions employed. Algae
products contain from 45% up to 80% carbon content in
the form of lipids/oils, carbohydrates, proteins and
hydrocarbons.
31. Alternative Fuels in Practice
• Between 2008 and 2011, at least ten airlines and
several aircraft manufacturers performed flight tests
with various blends containing up to 50% biojet fuel.
These tests demonstrated that biojet fuel was
technically sound, and the following observations
were made: No modifications to the aircraft were
required
• Biojet fuel could be blended with conventional fuel
• The engine powered on the biojet mix even showed
an improvement in fuel efficiency in some cases
32. Production and Impact on Net Emissions
• The main challenges to a wide deployment of biojet fuels are
not technical, but commercial and political.
• Currently, biojet fuels are significantly more expensive than
Jet A/A1, therefore demand is low and risk is high for
investment in production infrastructure. Carefully designed
policy is needed to foster investment and development of
biojet production capacity.
• A three percent volume blend-in of sustainable second
generation biojet fuel yearly worldwide would reduce
aviation CO2 emissions by about two percent, which would
be a reduction of over 10 million tonnes of CO2. This would
require investment of around $10-15 billion in production and
distribution facilities.
33. The Five easy steps to growing available
Aviation Biofuel Industry
Many of the technical hurdles facing aviation in
its move towards sustainable aviation biofuels
have now been overcome and much of this
work has been achieved within the industry.
Now, commercialisation and scaling up of the
supply of aviation biofuels is the most
important task.
The role of government in these five steps are:-
34. First Step:-Foster research into new
feedstock sources and refining
processes
• There are many different types of feedstock
and pathways that enable feedstock to
be converted into biofuel, and important
technological developments will unlock still
more pathways.
• The industry is unlikely to rely on a single
feedstock. Some feedstocks are better
suited to some climates and locations
than others.
35. • Several pathways are being considered for
the development of sustainable aviation
biofuel and these are illustrated below.
36. Second Step:-De-risk public and private
investments in aviation biofuels
These incremental upfront capital investment costs
are a potential barrier to commercialisation. In
this context, governments can play a role in
reducing this risk through measures such as loan
guarantees, tax incentives, grants and co-
financing for pilot and demonstration projects.
They can also provide a level playing field with
biodiesel by providing similar fiscal and price
incentives in order to catalyse establishment of
the sector.
37. Third step:- Provide incentives for airlines to
use biofuels from an early stage
Policymakers can foster development of aviation
biofuel by recognising the unique role it can have
in reducing the aviation’s environmental impacts.
Aircraft cannot use alternative renewable energy
sources available to other sectors such as plug-in,
wind, solar or hydroelectric power. Thus, crafting
policies that create a level playing field for
biofuels vis-à-vis other energy sources, and
aviation visà-vis other sectors, is a key element in
aviation biofuels commercialisation
38. Fourth Step:- Encourage stakeholders to
commit to robust international sustainability
criteria
The development of an accepted set of globally
harmonised standards will help ensure that
investment is directed at biofuels that meet
acceptable sustainability criteria, thus minimising
this form of risk. Criteria need to be mutually
recognised around the world. For aviation, global
standards are needed wherever possible, due to
operational routing of aircraft, common global
equipment and worldwide fuel purchasing
requirements.
39. Fifth Step:- Establish coalitions
encompassing all parts of the supply chain
Those seeking to better understand potentials
for this industry should engage with the
processes identified in this publication to
understand next steps in each region.
40. Advantages of biofuel
• Made from Renewable Resources
• Greener' Output
• No Mechanical Changes Required
• End of Fuel Monopolization
41. Disadvantages of biofuel
• Energy output: Biofuels have a lower energy
output than traditional fuels
• Food shortage may become an issue with
biofuel use.
• High cost: To refine biofuels to more efficient
energy outputs, and to build the necessary
manufacturing plants
• Water use: Massive quantities of water are
required for proper irrigation of biofuel crops
42. Smarter Skies
• The Future of aviation concentrates on just
that and the Smarter Skies vision consists of
three concepts which could be implemented
across all the stages of an aircraft’s operation
to reduce waste in the system (waste in time,
waste in fuel, reduction of CO2) and would
lead us to energy efficient aviation
infrastucture.
• The three concepts are:-
43. 1. Eco-climb
• Aircraft launched through assisted takeoffs using
renewably-powered, propelled acceleration will allow
for steeper climb from airports to minimise noise and
reach efficient cruise altitudes more quickly.
• As space becomes a premium and mega-cities a reality,
this approach also could minimise land use, as shorter
runways could be utilised.
• A continuous "eco-climb" would further cut noise and
CO2 emissions, especially if renewable fuels were used,
making the process even more eco-efficient.
44. 2. EXPRESS SKYWAYS
• In the future, highly intelligent aircraft would be
able to “self-organise” and select the most efficient
and environmentally friendly routes (“free flight”) -
making the optimum use of prevailing weather and
atmospheric conditions.
• High-frequency routes would also allow aircraft to
benefit from flying in formation like birds during
cruise bringing efficiency improvements due to drag
reduction and lower energy use.
45. In a V formation of 25 birds, each can achieve a reduction of induced drag by up to 65 per
cent and increase their range by 7 per cent. While efficiencies for commercial aircraft are
not as great, they remain significant.
46. 3. GROUND OPERATIONS
• On landing, aircraft engines could be switched off
sooner, runways cleared faster and ground
handling emissions could be cut.
• Technology could optimise an aircraft’s landing
position with enough accuracy for anautonomous
renewably-powered taxiing carriage to be ready,
so aircraft could be transported away from
runways quicker, which would optimise terminal
space, and remove runway and gate limitations.
47. Conclusion
• In the near future the use of bio fuel and fuel cell
technology will be used at a vast scale, but a lot more
research into it is needed.
• It is very important to look at more alternatives for the
fossil fuels since they are depleting at very high rate.
• Also, the aviation industry has been successful in
bringing the fuel consumption and CO2 emissions
down by a great amount in last few decades.
• I am sure this industry will also be successful in the
coming decades to lead us to a ‘Energy Efficient
Aviation Infrastructure’