Aviation and the Environment 3
Aviationand the Environment
Aviationand the Environment
Theaviation remains a key propeller of globalization and ultimately thegrowth of global GDP by promoting global business. Globalcontribution of the aviation industry whether direct, indirect,induced or through tourism stood at an estimated $2.2 trillion in2013 representing 3.5 percent of global GDP (Air Transport ActionGroup 2014). These figures are expected to soar as the demand foraviation increase with forecast for 2050 at an annual estimate of 4.5percent (ATAG 2014). Air transport has increased people’s mobilityworldwide leading to growth of other sectors such as hospitality andtourism.
Figure 1: Aviation’s global employment and GDP impactSource: ATAG 2014
Nevertheless, this growth has come at a priceto the environment in terms of air and noise pollution. Climatechange has been a dominating discourse in the recent times especiallywhen the climate change effects such as global warming becomeevident. The aviation sector contributes releases greenhouse gasessuch as CO2,whichis a major contributor of the greenhouse effect. The greenhouseeffect is believed to cause global warming and climate change
Effortsto mitigate climate change have been initiated in various industriesincluding the transport sector. However, aviation sector emissionsare not strictly incorporated in the Kyoto protocol rather it is leftto the International Civil Aviation Organization (ICAO). ICAO,therefore is responsible of coming up with guidelines to implement ashared actions plan and roadmaps to reduce environmental pollutionemanating from the aviation sector. ICAO has set targets to capaviation CO2and adopted a carbon neutral growth. The International Air TransportAssociation (IATA) has set four pillars to meet the targets for acarbon neutral growth that will drive an efficient and sustainableair transport industry. The air transport continues to witnessenormous growth and with this growth, sustainable growth anchored oneconomical, social, and environmental factors is vital for theaviation industry of the future.
Inorder to achieve a sustainable aviation industry, the industryplayers including IATA embarked on strategies to meet targets formitigating greenhouse gases (GHGs) set out by ICAO. These targetsinclude a cap on aviation CO2emissions from 2020 to experience a carbon-neutral growth (CNG).Secondly, the ‘green vision’ aims at an average improvement infuel efficiency of 1.5% per year from 2009 to 2020. Thirdly, toreduce CO2emissions by 50 percent by 2050 compared to 2005 levels(InternationalAir Transport Association 2013).The international air transport association (IATA) together with theinternational civil aviation organization (ICAO) developed a strategyto ensure the industry met its targets. This strategy known as the4-pillar strategy encompasses support in the area of improvedtechnology, effective operations, efficient infrastructures, andpositive economic measures (IATA 2013).
- Challenge Facing the Industry
Improvedtechnology predicts the best model of reducing aviation emissionsvested on innovative aircraft designs and aerodynamic systems andbiofuels. Modern technologies such as winglets and laminar flowtechnology are projected to reduce emissions by 1 % by 2020 (IATA2013). However, the costs of transitioning to these new technologiesremain a challenge to the industries. Biofuels have been cited as aneffective method of reducing emissions. However, the sustainabilityof biofuels remains is a ranging debating on the social andeconomical perspective. Operations practices such as reducing the useof APU, efficient flight procedures and strict passengers’ luggageregulation may reduce cost and lower emission. These efforts havebeen credited to the ‘green teams’ that have been formed by IATA.In the infrastructure pillar, improved infrastructures such as in theSingle European Sky (SES) project are predicted to reduce emissionsubstantially. However, such projects require the cooperation ofcountries making them a complex challenge. Standardizinginfrastructures and harmonized airspace such as the SES project thatwill require countries to make decision that may conflict with theirsovereignty.
Economicmeasure is a wide-ranging pillar that influences the other threepillars. The economic status affects the implementation of the carbonscheme. The realization of the 90 million tonnes cut in CO2emissions between 2020 and 2025 will require sound economic measureswithout which these goals would not be achieved. Operations andadoption of new technology in the aviation sector is a factordependent on the economic measures in place. The aviation industrygoal is to provide air transport that leaves a small physical carbonfootprint with less CO2emissionas it gears towards a carbon-neutral growth.
Advancedtechnology is being introduced and old fleets that are inefficientreplaced with new aircrafts to reduce pollution and improveefficiency. However, the rapid growth of the number of carriers inthe airspace continues to outstrip these efforts (Lee etal.2001). This challenge warrants the development of State-of-the-ArtTechnology will support the reduction of emission as the air-trafficsoars (Lee etal.2001). In the recent times, the aviation industry has faced increasedoperational costs and slow growth in revenues (Air Transport ActionGroup 2014). These challenges curtail the achievements of the targetsset out by the ICAO and attainment of the 4-pillar IATA strategy.Prices for the State-of-the-Art technology remain high furtherlimiting the achievements of the sustainable measures laid down bythe aviation industry.
Emissionsreduction for a carbon neutral growth relies on three key areasnamely, innovative engine technologies and aerodynamic designs, useof alternative fuels such as biofuels and the improvement in ATM andoperations.
Figure2: Forecasted Carbon Neutral Growth towards 2050 centered ontechnology
- An Analysis of the Technology Pillar
Technologyis mentioned as a major driver towards the attainment of thesustainable targets through the strategies envisioned by IATA.However, these strategies seem too ambitious to attain the set outtargets given the long production cycle and service life of anaircraft. Expected expansion of Asian and other developing countrieswill mean efforts to have a sustainable aviation industry may besurpassed by the dramatic increase in flights and passenger miles.However, large-scale production and use of aviation biofuels remainas an effective way of offsetting the potential greenhouse gasemission as a result of the expected growth.
Biofuelsremain the best alternative to fossil fuels in creating a sustainableaviation industry of the future. However, there remains a discourseon the neutrality of biofuels (International Civil AuthorityOrganization, 2012). This discourse has been on the lifecycle of thebiofuels and the land use change as land is converted for biofuelsproduction. There is an apparent lack of additional carbonsequestration and also the effect of increased biofuels use on humanfood prices.
Therefore,the industry faces the challenge of identifying and developingaviation biofuels, which do not compete with food production.Although, both biofuels and fossils fuels emit CO2emissions biofuels are environmentally sustainable based on thelifecycle assessment (LCA). Fossils fuels reintroduce new CO2intothe atmosphere unlike aviation biofuels that recycle CO2already in the atmosphere, as they are plant-based. Alternativeaviation biofuels focuses on reducing the net carbon independent ofthe amount of fuel burnt which is the main focus of engine, airframe,and ATM technologies.
Asevident in figure 3, technology remains the single most pillars toeffectively curb green house gas emissions under the ICAO targets.This encompasses fleet renewals, engine retrofits, and airframetechnology. Despite the European Union embarking on a mission to curbby extending the EU ETS to the aviation industry, several countriesincluding US, China and Russia are in opposition. The EU ETS aims atreducing GHGs by creating a regime that puts a price on emissions.Air traffic management and incorporating efficient materials inaircraft building may lead to significant cut in greenhouse emission.Two next generations ATM systems have been in development i.e. the USNextGen and the European SESAR.
Figure3: IATA commitment to CO2reduction strategy (Source: ATAG 2014)
Retrofittingexisting aircrafts may in the meantime assist in reducing emissionfor the short-term. However, long-term abatement of GHGs emissionwill require the design and development of lightweight compositematerials that will relatively reduce GHGs.
Improvementin fuel efficiency by jet engine manufacturers has been a continuouseffort towards abating emissions. These efforts include thedevelopment of advanced turbofan engine designs. Although theaviation industry has witnessed an annual improvement in fuelefficiency of 1.5% from the 1960s to 2008, there has been plateaugrowth as a result of slow technological advances in the past decadeto present (EuropeanFederation for Transport and Environment, 2010).Efficiency has been overrun by the need to boost aircraft performancein terms of range and speed. These measures are market-based and theyconstrain the strategic pillars towards the targets for a sustainablefuture aviation industry. However, the industry has embarked onimproving fuel efficiency of up to 70%, which also is geared towardsreducing operational costs (EuropeanFederation for Transport and Environment, 2010).
Europehas continued adopting comprehensive approaches apart from technologyand operational measures to combat GHGs emissions. These measures arebased on market incentives deployed as emissions charging schemessuch as the EU Emissions Trading Systems(ETS) resulting in CO2reduction of 65 million tonnes between 2013 and 2016 (EuropeanFederation for Transport and Environment, 2010).
Managementof airports exists in IATA’s strategic pillars to curb greenhousegases emissions and achieve carbon neutral growth. Airports seek tohave effective operations and efficient infrastructures that willdrive the aviation industry into meeting the ICAO targets.Infrastructure enhancements such as the Green building initiativeshelp airports improve their environmental impact as they decreasetheir emissions and improve on energy conservations. The greenbuilding initiatives emphasize the reliance on natural lighting andinstallation of green roof to conserve energy. Such practicalenvironmental activities have been implemented in a number ofairports including Chicago’s O’Hare, Seattle-Tacoma, andWashington Dulles International Airports. The Airports CouncilInternational-North America (ACI-NA) reports at least 24 airportshave adopted formal environmental management systems. These systemsare a framework of processes and practices that help the organizationto curb its environmental impact and at the same time improve onoperating efficiency.
Althoughaircrafts operation remains the main source of CO2emissions, airports such as those belonging to the ACI-NA haveadopted measures aimed at mitigating emission with their controlthrough operational and infrastructure improvements. Airports such asin Burlington, Las Vegas have adopted alternative-fueled airportvehicles. Other measures include equipping loading bridges with powerto avoid aircraft engine and APU usage.
Airportscontribute a significant portion of the carbon emission in theaviation industry. This emission is through heating and power at theairport. However, aircraft contributes a larger share of theseemissions such as in taxiing. Aircraft landing and take-off arecritical stages of flight that contributes significantly to carbonemissions. In reducing, emissions around airports measures such ascontinuous decent approach and continuous climb departure can beadopted (Sustainable Airport, 2012)
Inthe United Kingdom, partial measures have been put in place todecouple emission growth from the future growth of the aviationindustry through a sustainable aviation. Such measures have beenenvisioned in improved aircrafts and increasing engine efficiency toimprove fuel efficiency (ICAO, 2012). A 50% reduction in the 2005levels of carbon dioxide emission can be achieved in 2050 byimplementing operational changes whilst advancing futuristicsustainable technologies in the industry. In achieving theseobjectives, the UK aviation industry has ensured that sustainableaviation fuels are available as well as carbon trading to encouragefuel efficiency amongst the airlines operating in the UK airspace.Incentives to promote research and development and commercializationof sustainable aviation fuels and technology should be put in placeby the stakeholders including the government to hasten the pacetowards the ICAO emissions targets (Sustainable Aviation, 2012).
Reducingemissions requires the innovation in aircraft design as well asairport and airline operational efficiencies. Improvements inaircraft design may involve increasing passengers/payload carried perunit distance. In assessing environmental performance, energyintensity is a prerequisite measure of efficiency (Tanaka 2008).Energy intensity can be reduced by improving the aerodynamicefficiency and increasing aircraft size. The high cost of new orimproved innovations in technology such new wing designs, airframematerial and jet engines is an impediment to the radical shift of theaviation industry towards sustainable environment performance.
Innovationin aircraft design has been driven by majorly fuel cost, globalclimate change and social factors (Lee& Mo, 2011).Since fuel is a significant portion of the airline operational cost,it drives the design and development of fuel-saving technologies,which also double as shift towards environmental performance andsustainability. Fuel efficiency is a principal driver of aircraftdesign since it relates to the payload-range performance. Aircraftmay not realize the dramatic improvement in environmental performancedue to innovations in aircraft design. This is due to the associatedcost of switching from one technology to another in the aviationindustry.
Inaddition, developing new aircrafts design is a monumental processthat takes a lot of time to be realized. This lag in adoption of newtechnologies will impede improvement in environmental performance asenvisioned in IATA targets. Technological advancement in the aviationindustry is thus a factor of cost and the existing market needs.
Thehigh cost in innovation in the aircraft industry results in theairlines investing in modest innovation in fuel-saving technologiesand operations. This has been a significant limitation of theaviation sector towards realizing dramatic environmental performance(Lee etal,2001). Another limitation of innovation is the apparent limitation ofaerodynamic and structural designs approaching the limits of physics.Drastic changes in aircraft design become a bottleneck and thereforethere is lack of radical technological and operational measuresintroduced in the sector. However, the development of high-energyaircraft such as Boeing 787 that consumes 20% less fuel than itscontemporary is one example of modern technology in aircraft designhaving a significant impact towards realizing ICAO targets(International Civil Authority Organization, 2012).
Operationalmeasures that are geared towards the targets include single-enginetaxiing that helps in reducing jet emissions in airports. Innovationin aircraft design and airline and airport operations favor gradualor incremental technological improvement rather than completeoverhaul of the design and build of the aircraft making dramaticimprovements in the environmental performance a mileage (Lee& Mo 2011).This is attributed to the associated cost in selling and buying newaircrafts. Therefore, measures such as use of biofuels instead offossil fuels are favored. The incremental improvement in aircraft ispreferred since its implementation guarantees medium sustainabilitythereby satisfying shareholders and stakeholders concerns (Lee& Mo 2011).
Althoughbiofuels have been cited as the future aviation fuels, they presentchallenges that may compromise the safety. For instance, studies haveshown that blending conventional fossil fuels with biofuels presentsafety issues during fight when deposits are left in the fuel systems(Hilemanetal.2009).Relative to jet A, ethanol as a biofuel has a low flash point and ishighly volatile resulting to more amount in a given distance comparedto jet A (Service 2010). This may be counterproductive towardsachieving sustainable aviation that is not reliant on fossil fuels.However, continued investment in research and development of aviationbiofuels will eventually lead to production of sustainable and safeaviation fuels.
TheICAO targets on global standards of CO2emissions have resulted in 70% more fuel-efficient aircraft (ICAO,2012). The design and performance of new double-decker usingcomposite materials has led to a reduction of GHGs emissions.
- Measurements of Targets
Technologicalmeasures may reduce the overall fuel efficiency and contribute toreduction of CO2emissions as laid down in the ICAO targets. The reduction of theoverall weight of the aircraft can be achieved by usingstate-of-the-art materials such as advanced alloys and compositesmaterials. For instance, the use of composite materials and lightermaterials such as fly-by-wire has been achieved in recent generationsof aircraft for instance the A380. The A380 is composed of 25%advanced materials, which have significantly reduced fuel usage, by8% compared to the traditional metallic materials (SustainableAviation, 2012). In the future, further measures such as the use of50% composite materials on wings and fuselage are projected to reducethe weight by 15%, hence improving fuel efficiency and loweringemission simultaneously.
Inachieving the targets, nanomaterials may be extended to the aviationindustry with the promise of further cutting the weight of theaircraft and improving efficiency. The nanomaterials may composenanofillers that can conduct electricity thereby reducing the needfor metallic grids or even ground wiring (Sustainable Aviation,2012). This may cut down on the additional weight. Othertechnological measures such as reduction of the aerodynamic drag thathas a direct effect on fuel burn have been implemented with the goalreducing friction drag by 50%.
Modernaircrafts such as the Airbus have incorporated advanced compositematerials that significantly lower lift associated drag by maximizingwing span extension (Sustainable Aviation, 2012). The continuedimprovement in the structural efficiencies of modern day aircraftsprovides the impetus for the realization of the 2050 targets for CO2emissions.There have been a number of projects geared towards the delivery ofefficient aircraft structures that will significantly cut down onfuel burns. For instance, the Very Efficient Large Aircraft (VELA)project is geared towards the delivery of blended wings that areforecasted to reduce per-seat fuel consumption by 32%. These effortsmay be a guarantee that despites the overall associated cost ofproviding a sustainable aviation industry, technology is stilladvancing towards achieving the ICAO targets. The current A380 forinstance has replaced the hydraulic systems in A350 with electricalsystems, thus reducing on weight with a comparable fuel saving. Fuelcells offer reductions in emissions as compared to auxiliary powerunit (APU) and have been tested and used in Airbus A320 (SustainableAviation, 2012).
Modernday technology has been re-energized by the availability ofcomputational modeling tools that enable physics-based modeling andoptimization of engine performance as well as the aerodynamicsproperties of the aircraft. In addition, the availability ofcomposite materials and nanomaterials will enable the retrofitting ofthe current fleets or even the design and development of morefuel-efficient aircrafts.
Theaviation industry performance based on the technological advancementto cut down on its carbon footprint can be measured via market-basedmeasures (MBMs). These measurements are under the scope of ICAOCommittee on Aviation Environmental Protection (CAEP). CAEP assessesthe achievement towards the ICAO targets based on technicalfeasibility, environmental benefits, the interdependencies of themeasures taken, international and national programmes, as well as theeconomic viability of such measures (InternationalCivil AuthorityOrganization, 2016).
Themarket-based aviation biofuels measurements are geared towardsdelivering biofuels that have minimal impact on biodiversity, producesignificantly lower lifecycle emissions as compared to fossil fuels.In addition, the aviation biofuels should deliver positivesocio-economical impacts and should be sustainable in aspects ofland, water and energy utilization (Sustainable Aviation, 2012). TheMBMs also ensure that aviation biofuels do not compete with foodcrops and do not drive deforestations otherwise their continued usebecomes counterproductive. Thus, in measuring aviation biofuels, thestandard has been the reduction in lifecycle greenhouse gasesemissions by 50%. In future, some regional bodies’ regulations,such as the European regulations aim to cap the lifecycle green housereduction to 60%. In addition, these measures seek to have biofuelswith reduced sulphur content thereby lowering air pollutions aroundairports (Sustainable Aviation, 2012).
Biofuelsmay not be as good as kerosene however, airlines have countered thischallenge by using sustainable drop-in biofuels, which do not requirechanges to the aircraft or the existing fuel delivery infrastructure(Sustainable Aviation, 2012). The current use of biofuels blendedwith kerosene and the drop-in fuels promises the realization of thegoals set out at the ICAO targets to cap on aviation CO2emissions from 2020 and experience a carbon-neutral growth.
- Barriers to Success
Thecost associated with incremental improvement of the aircraft fleet isa significant barrier towards achieving the ICAO goals. Improving theaerodynamics of the aircrafts requires a significant investment innew aircraft (). This competes with the shareholder interest ofincreasing profits for the short-term. In addition, there exist noglobal incentives for improving aircraft emissions by improving theiroverall emissions. Although the EU-ETS exists, it only regulates andprovides carbon emissions capping incentives to the airlines flyingin and from the EU member countries. In addition, aviation industriesneed to realize similar growth with airlines from developingcountries so that there can be uniform adoption of technologies. Inaddition, there are no uniform regulations across the globe thatattempts to guide the realization of the ICAO targets. Thus, otherincentives such as passengers’ preference for airlines adhering to‘green’ technology and the shareholders goals of achieving acarbon neutral growth come into play (ICAO, 2013).
Althoughaviation biofuels remain a key driver to sustainable futuristicaviation industry, there are significant barriers towards the use ofbiofuels. Availability of sustainable feedstock for the production ofbiofuels and the overall impact on environment in the long-term is asignificant challenge. Short-term goals for replacement of fossilfuels with biofuels include the economic cost associated with theresearch and development of biofuels (Outcomesof ICAO’s SUSTAF Experts Group, 2013).
Competitivenessof biofuels in comparison to the fossils remains a challenge in theiradoption. Competitiveness of biofuels is hindered by their overallhigher costs than fossils fuels and a lack of an appropriatemechanism to compensate the airlines in the initial phase of aviationbiofuel use (Outcomesof ICAO’s SUSTAF Experts Group, 2013).Hence, the viability of biofuels is anchored on their competitivenessin times of costs in development and their price. Aviation requiresdrop-in fuels a technology that is present in conventional keroseneand requires advanced processes to be achieved in aviation biofuels.
- Recommendations for Achieving Success
Technologyremains the most effective pillar of the four-pillars strategies setup by IATA to accomplish the laid down targets for a sustainableaviation industry. This pillar guarantees substantive reduction inCO2emissions, unlike the other three pillars, however it requiressignificant investment. It will provide the effective and meaningfulreduction of CO2emissions. However, the bottleneck of slow technological developmentand the associated high cost of adopting new technologies portend achallenge to the realization of the targets. This work recommendsgradual improvement in the existing aircrafts in terms of wing refitsto cut down on inefficiency and reduce overall CO2emissions. The associated high cost of new technology may conflictwith shareholders interest. However, medium improvement in technologyrather than complete overhaul of the existing technologies mayaddress the shareholders/stakeholders concern while simultaneouslycurbing emissions.
Accelerationof the aviation biofuels use requires increased investment towardsthe commercial production of efficient biofuels and reduces theircost of feedstock and biofuel production. This has the downstreameffect of increasing their competiveness and use as alternative toconventional fuels.
Biofuelsprovide alternatives for the fossil fuels. Biofuels recycleatmospheric CO2makingthem the best suited in reducing CO2drastically within a short time. However, more research on theirlong-time viability is needed. Further, blending them with fossilfuels provides a compromise where their efficiency is doubted. Theaviation industry should continue initiating and investing inresearch and development of aviation biofuels capable to substitutethe fossils fuels. These aviations biofuels should more or lessperform optimally using the same systems without resulting inincreased cost. In addition, land management and issues on biofuelscompeting with food crops should be addressed. Incentives should beprovided in research and development of aviation biofuels.
Thereduction of green house gases has been a success in Europe. This hasbeen due to the European adoption of transport paper, which aimed atreducing overall emissions in the transport sector by 60 % by 2050.This transport policy prioritizes on biofuels as a long-term strategyto reduce CO2emissions. This has led to the launch of the European Biofuels FlightPath project in 2011 aimed at developing aviation biofuels.
Fuelconstitute a significant proportion of the operation cost and thishigh cost translates to an incentive for the airlines to befuel-efficient and consequently to invest in the development ofsustainable aviation biofuels. First flight on biofuels took place in2008 with the aim of investigating the feasibility of aviationbiofuels. This success was followed by the approval of hydrotreatedrenewable jet, biomass-to-liquid biofuels in 2011. Although thechallenges of feedstock remain, the aviation industry is ready toadopt the use of biofuels given their environmental performance. Thiswill require continued investment in research and development in theoutputs and efficiency of aviation biofuel so that the aviationindustry can be guaranteed of their sustainability. This will lead tocommercialization of these aviation biofuels through efforts such aspublic-private cooperation. In order to encourage the development ofsustainable aviation biofuels, the EU Emission trading system hasawarded biofuels a CO2emission rating.
Inaddition, realistic goals towards achieving success in a sustainableaviation industry will encompass implementing a global CO2emissioncap structured under the Kyoto protocol, which will ultimatelyintroduce measures such as emissions charges and enforcecarbon-offset programmes across all airlines. In addition, increasethe implementation of alternative technology to guarantee a carbonneutral growth in the sector. Further, improvements in aircrafttechnology efficiency is requires as well as close cooperationbetween stakeholders in the aviation industry in the development ofadvanced technologies that will catapult the industry towards a zerocarbon emissions growth.
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