Aviation Initiatives and the Relative Impact of Electric Road Vehicles and Biofuels on CO2 Emissions

Transcription

1 Aviation Initiatives and the Relative Impact of Electric Road Vehicles and Biofuels on CO2 Emissions Jose Alexandre T.G. Fregnani, and Onofre Andrade Abstract This paper discusses the global efforts to develop mechanisms for the industry to meet its ambitious goals for reduction of greenhouse gas emissions. It presents scenarios related to a steady increase of the electrical vehicle fleet in combination with increasing use of aviation biofuels, and discusses the impact of CO 2 emissions and noise levels in the global transportation sector through the year The conclusion is that, despite overall emissions reductions, there is significant evidence that the aviation industry will continue to be one of the focus areas for socio-political pressure in years to come. It reinforces the need to invest in sustainable aviation biofuels and the development of aircraft/engine design, alternative propulsion, and other sources of energy to power aircraft systems to improve operational efficiency. Another conclusion is that even with major achievements in the above areas, there will be a need for a global mechanism that would allow the aviation industry to meet its pledge to reduce greenhouse gas emissions and its carbon neutral growth commitment. Index Terms Electrical Vehicles Emissions, Aviation Biofuels, Aviation Emissions, GHG effects, Operations Efficiencies, New Aviation Technologies, CORSIA. (CO 2), which comprises about 70% of the exhaust, and water vapor (H 2O), which comprises about 30% [1]. Less than 1% of the exhaust is composed of pollutants like nitrogen oxides (NOx), oxides of sulfur (SOx), carbon monoxide (CO), partially combusted or unburned hydrocarbons (HC), particulate matter (PM), and other trace compounds. In general, about 10 percent of aircraft pollutant emissions are emitted close to the surface of the earth (less than 1000 meters above ground level), the remaining 90 percent of aircraft emissions are released at altitudes above 1000 meters. The aviation industry has made great efforts to lower aviation-related emissions such as the use of alternative fuels, improved airplane designs, new aircraft concepts, and fuelsaving operational procedures. The International Civil Aviation Organization (ICAO) proposed a Four Pillar initiative with the objective to address emission reduction targets [2] including investments in operational procedures, infrastructure, technology and market-based measures. Besides ICAO, several governments that have been issuing policies to address pollution caused by aircraft but it has been difficult to reach global agreement (see EU initiative to aviation emissions in its Emissions Trading Scheme). Despite such efforts, the aviation industry could see its share of overall global emissions change significantly if electric road vehicles gain more widespread use. I. INTRODUCTION Transportation plays a vital role for the strengthening of the economy worldwide. Within the transportation sector, commercial aviation has evolved from the 1960s to present days into the fastest, safest and global transportation mode. Nowadays, over 3 billion people, nearly half the world s population, use regular air transport, whose industry generates on a worldwide scale 56 million jobs, both direct and indirect [1]. Aircraft carry only 0.5% of the world s trade shipments, but represents about 35% of the value of all world trade. This productivity is achieved while consuming just 2.2% of the world s energy [1]. Aircraft engines produce carbon dioxide II. AVIATION IN A GLOBAL WARMING ENVIRONMENT Global warming and climate change can both refer to the observed century-scale rise in the average temperature of the Earth's climate system and its related effects (Fig. 1). Multiple lines of scientific evidence show that the climate system is warming [5]. More than 90% of the additional energy stored in the climate system since 1970 has gone into ocean warming; the remainder has melted ice, and warmed the continents and atmosphere. Many of the observed changes since the 1950s are unprecedented [5]. Copyright 2017 Boeing. All rights reserved.

2 Figure 1: Published records of surface temperature change over large regions (Source: IPCC). The transport sector plays a major role in world energy use and emissions of greenhouse gases (GHGs). In 2004, transport energy use amounted to 26% of total world energy use and the transport sector was responsible for about 23% of world energy-related GHG emissions [7]. Virtually all (95%) of transport energy comes from oilbased fuels, largely diesel (23.6 EJ, or about 31% of total energy) and gasoline (36.4 EJ, 47%). One consequence of this dependence, coupled with the only moderate differences in carbon content of the various oil-based fuels, is that the CO 2 emissions from the different transport sub-sectors are proportional to energy use (Fig.2). Figure2: Energy consumption and CO 2 emission in the transport sector (source: IEA). The mitigation of environmental impact is one of the key challenges for aviation and a main driver for research and technology in the sector. While the focus in the past was on noise and local pollutant emissions, aviation greenhouse gas emissions have become the predominant environmental topic for the aviation community in the last years. Modern airliners are powered by turbofan or turboprop engines burning kerosene, which is a mixture of hydrocarbons and contains a large variety of carbon chain molecules, generally with chain lengths of nine to sixteen atoms. This is the case with JET A- 1 fuel produced according to international standard specifications for use in civil aviation. According to the Intergovernmental Panel on Climate Change (IPCC) in 2007 [17], the CO 2 emissions from global aviation were increased by a factor of about 1.5, from 330 MtCO 2/year in 1990 to 480 MtCO 2/yr in 2000, and accounted for about 2% of total anthropogenic CO 2 emissions. Taking into account also other relevant exhaust emissions from aircraft engines including contrails and cirrus, the contribution of air transport to the total anthropogenic greenhouse effect has been estimated at around 3%. IPCC [17] also concluded that, in the absence of additional measures, projected annual improvements in aircraft fuel efficiency of the order of 1 2% are likely to be overlapped by traffic growth of around 5% each year, despite political and economic turmoil, leading to a projected increase in emissions of 3 4% per year. IPCC also forecasts that by 2050 aviation contribution to global anthropogenic carbon emissions could grow to 3%, representing 5% of the total greenhouse effect [18]. While aviation is a relatively small contributor of greenhouse gases, the scientific findings of the IPCC [18] show a clear urgency for action from all sectors to achieve their medium and long term objectives. Therefore, emissions reduction measures were perceived by the industry as a real need for compensation of the effect of the traffic growth forecasted. III. IMPACT OF ELECTRICAL ROAD VEHICLES FLEET EXPANSION ON AVIATION An electric car is an automobile that is powered by one or more electric motors, using electrical energy stored in batteries that can be recharged or another energy storage device. Electric motors give electric cars instant torque, enabling smooth, high acceleration. In average, electric ground vehicles are also around three times as efficient as cars with an internal combustion engine. Electrical vehicles (EVs) emit no tailpipe pollutants, although the power plant producing the electricity may emit them. However, there are environmentally friendly sources of energy such as those making use of wind and solar energy. In addition, EVs produces a direct benefit to cities, considering that ground vehicles powered by internal combustion engines are the major contributors to their local air pollution and power sources are usually located far from them. There are only few studies on the impact of electrical road vehicles in the emission picture in the transport sector, and they disagree significantly with each other regarding their conclusions on the subject. Many researchers claim that the electrical road vehicles will not contribute to lower emission levels in the whole chain, considering that the energy necessary to produce batteries and to power those vehicles will be higher than current levels. However, a recent report from Electric Power Research Institute (EPRI) and Natural Resources Defense Council (NDRC) affirms that the electrical vehicle emission levels are far lower than the pollution caused by conventional vehicles, and could be even

3 lower if the electric power sector cleans itself up over the next few decades [4]. The EPRI-NRDC study, took into account some potential scenarios for the electricity sector of the future and the potential emission impact of widespread electrification displacing petroleum consumption in the transportation sector. To address the first issue, two potential greenhouse gas scenarios of the future electric power sector were considered: namely the "Base GHG" and "Lower GHG" scenarios. Both revealed that grid emissions will decrease over time, in part because of existing and potential regulations and plausible economic conditions. In the Lower GHG scenario, an increasing price on carbon is supposed to further reduce carbon emissions, as it could result in faster deployment of low-emission generation technologies. In the Base GHG scenario, the study estimates that, by 2050, the electricity sector could reduce annual greenhouse gas emissions by 45% or 1030 million metric tons relative to 2015 levels. In the Lower GHG scenario, the study estimates that, by 2050, the electricity sector could reduce annual greenhouse gas emissions by 77% or 1700 million metric tons relative to 2015 levels. The EPRI-NDRC report also analyzed electric sector and transportation sector emissions with and without widespread utilization of electric road vehicles to determine the effect of electrification of light-duty personal vehicles, some mediumduty commercial vehicles like local delivery trucks and certain non-road equipment, like forklifts. It was found that electrification could displace emissions from conventional petroleum-fueled vehicles for each scenario: In the Base GHG scenario, carbon pollution is reduced by 430 million metric tons annually in 2050 equivalent to the emissions from 80 million of today's passenger cars [4]. In the Lower GHG scenario, carbon pollution is reduced by 550 million metric tons annually in equivalent to the emissions from 100 million of today's passenger cars [4].Independent from these results, there are good perspectives that the electrification of road vehicles will change the emission panorama of the transportation sector. This will make the cities less polluted and quieter, changing the public standard for acceptable noise and emission levels. Electrical vehicles have gained steady acceptance among the public and are being supported by some governmental policies worldwide, due to its appeal to lower emissions and almost absence of noise. According to InsideEVs.com, total sales of EVs in the United States rose 23% annually in Boeing forecasts that the demand for airliners ranging from regional jets to widebody airplanes will grow an average of 3.6% a year in the timeframe [27]. The airliner fleet will grow from 21,600 in 2014 to 43,560 in 2034 [27]. If in coming decades the sales or electric vehicles soars, considerably replacing internal combustion vehicles, the noise and emission percentage caused by road vehicles will drop significantly. In this possible scenario, the relative contribution of aviation to emissions and noise will be raised to new heights. How will the public, government, industry and academy accept this? In order to answer the question, it is necessary to utilize existing estimations of the pollution caused by different means of transportation. The International Energy Agency (IEA) has worked with the world Business Council for Sustainable Development (WBCSD) in its Sustainable Mobility Project (SMP) to develop a global transport spreadsheet model that can serve both organizations in conducting projections and policy analysis [28]. The SMP transport spreadsheet model is designed to handle all transport modes and most vehicle types. It produces projections of vehicle stocks, travel, energy use and other indicators through 2050 for a reference case and for various policy cases and scenarios. It is also designed to have some technology-oriented detail and to allow fairly detailed bottomup modelling. The SMP emission forecast for air transportation utilizes a fairly simplified approach: passenger kilometers (actually revenue passenger kilometers, RPK) are multiplied by energy use per RPK (energy intensity) in order to derive energy use. CO2 emissions are estimated based on fuel use. Domestic and international air travel in each region are treated together. The road vehicles were supposed to burn fossils fuels or some types of biofuels. Table 3 displays the projection of CO 2 emissions [23] obtained from the SMP project spreadsheet, whose data and projections is summarized in Fig. 4. Aviation total CO 2 emissions will jump from 13.2% in 2000 to 19.5% in year Year Road Aviation Maritme Road Total Aviation Total Maritme Total % 13.20% 9.40% % 14.00% 10.50% % 14.30% 9.50% % 14.30% 11.40% % 14.50% 10.50% % 15.90% 9.80% , % 17.00% 9.10% % 17.00% 8.50% % 18.10% 8.80% % 18.20% 9.10% % 19.50% 7.60% Table 1: Projected CO 2 emissions (Gt and percentage) by modes until 2050 (Source: IEA and WBCSD). Figure 4: Historical and projected CO 2 emission from transport by modes in the period (Source: IEA and WBCSD). Tables 2a and 2b show the estimation of aviation participation in global CO 2 emissions if electric road vehicles increasingly replace internal combustion engines (ICE), with

4 and without the introduction of aviation biofuels. These kind of alternative fuels produce, considering the whole logistics value chain, in average 70% less emissions when compared with fossil fuels. In addition, both tables consider that electrical road vehicles will produce 80% less emissions than the ones using conventional fossil fuel engines. For instance, not considering the use of aviation biofuels, in 2030, 25% of all road vehicles will be electric and the aviation share in emissions will be 20%, 3% above if no EV would compose the fleet of road vehicles. However, if the use aviation biofuels are considered, according to IE data, this energetic source is estimated to be used in 5% of the flights in 2030), the aviation emissions share drops to 19.4%. % Evs in the Aviation impact Aviation impact Year world fleet on global CO2 on global CO2 Difference (% ) emissions emissions without Evs with Evs % 13,2% 13,2% 0,0% % 14,0% 14,0% 0,0% % 14,3% 14,3% 0,0% % 14,3% 15,2% 0,9% % 14,5% 15,9% 1,4% % 15,9% 18,0% 2,1% % 17,0% 20,0% 3,0% % 17,0% 20,7% 3,7% % 18,1% 25,6% 7,5% % 18,2% 34,0% 15,8% % 19,5% 46,7% 27,3% Table 2a: Aviation Contribution on CO 2 Emissions related to Transportation Systems (EV efficiency = 80% and airplanes will not use biofuels). Biofuel use Aviation impact Aviation impact Year (share on total on global CO2 on global CO2 Difference (%) Aviation Fuel Volume) emissions emissions without Evs with Evs % 13,2% 13,2% 0,0% % 14,0% 14,0% 0,0% % 14,3% 14,3% 0,0% % 14,3% 15,2% 0,9% % 14,4% 15,8% 1,4% % 15,6% 17,7% 2,1% % 16,5% 19,4% 2,9% % 15,9% 19,4% 3,5% % 16,3% 23,2% 6,9% % 15,1% 29,3% 14,1% % 14,5% 38,1% 23,6% Table12b: Aviation Contribution on CO 2 Emissions related to Transportation Systems (EV efficiency = 80% and airplanes will utilize biofuels) Tables 4c and 4d consider less efficient electrical road vehicles (20% less emissions than the ones using conventional fossil fuel engines) with and without aviation biofuels utilization. Figure 4 plots the data contained in Tables 4a, 4b, 2c and 2d. % Evs in the Aviation impact Aviation impact Year world fleet on global CO2 on global CO2 emissions emissions Difference (% ) without Evs with Evs % 13,2% 13,2% 0,0% % 14,0% 14,0% 0,0% % 14,3% 14,3% 0,0% % 14,3% 14,5% 0,2% % 14,4% 14,8% 0,4% % 15,6% 16,3% 0,7% % 16,5% 17,7% 1,2% % 15,9% 17,8% 1,9% % 16,3% 19,6% 3,3% % 15,1% 20,6% 5,5% % 14,5% 22,8% 8,3% Table 2c: Aviation Contribution on CO 2 Emissions related to Transportation Systems (EV efficiency = 20% and airplanes will not use biofuels). Biofuel use Aviation impact Aviation impact Year (share on total on global CO2 on global CO2 Aviation Fuel Volume) emissions emissions Difference (%) without Evs with Evs % 13,2% 13,2% 0,0% % 14,0% 14,0% 0,0% % 14,3% 14,3% 0,0% % 14,3% 14,5% 0,2% % 14,4% 14,7% 0,3% % 15,6% 16,0% 0,5% % 16,5% 17,2% 0,6% % 15,9% 16,7% 0,8% % 16,3% 17,6% 1,3% % 15,1% 17,2% 2,1% % 14,5% 17,1% 2,7% Table 2d: Aviation Contribution on CO 2 Emissions related to Transportation Systems (EV efficiency = 20% and airplanes will utilize biofuels) Figure 4: Aviation contribution with global CO 2 emissions considering an increasing EV fleet over time. Considering the presented data: 1. The aviation biofuels reduction of CO 2 emissions was considered to be effective from 2020, according to IEA. For example, by 2050, considering 100% of road vehicles being electrical ones, aviation contribution would be increased by 27.3% if no biofuels are used (biofuels are expected to achieve an average of 60% of GHG reductions in the time frame considered [7]) 2. In 2050 under the most pessimistic scenario for aviation, when 100% of the road vehicles would be electrical (with maximum efficiency 80%) and no

5 biofuels are used, the participation of aviation on transport CO 2 emissions would be 46.7%, 3.3 times greater than 2005 levels (considering that no EVs and no biofuels are present). 3. In 2050, under the most optimistic scenario for aviation, if 100% of the road vehicles present only 20% efficiency (technology has not evolved so far...) and aviation biofuel is used on 43% of the flights, the participation of aviation on transport CO 2 would be 17.1%, approximately 1.2 times greater than 2005 levels (considering no EVs and no biofuels are present). The evident conclusion is that even introducing biofuels on aviation operations, the increasing demand for electrical road vehicles would lead aviation to a scaling increase its share on transportation emissions throughout the year 2050, despite the overall emissions reduction. In other words, there is significant evidence that aviation will be more and more in focus (and also social-political pressure) throughout the years regarding the GHG emissions. This fact obviously reinforces the necessity of improvements of aircraft/engine design, alternative engines, and other sources of energy to power aircraft systems and improvements in operational efficiencies. IV. AVIATION INDUSTRY INITIATIVES Considering the above scenario, at the United Nations Climate Conference in Copenhagen in 2009 (two years after the IPCC report), the aviation industry (airlines, manufacturers, airports and air navigation service providers) announced its commitment to a global approach to mitigating aviation greenhouse gas emissions, setting the following objectives: 1. Improvement in fuel efficiency of 1.5% per year from 2009 to 2020 (measures that industry can control, linked to operational procedures and basic infrastructure improvements). 2. Carbon-neutral growth at 2020 (fuel CO 2 emissions are neutralized). 3. Reduction in CO 2 emissions to 50% of 2005 levels by It is noticeable that this is actually a very ambitious roadmap where the aviation industry would invest heavily and continuously on new technologies. Focus on fuel efficiency turned therefore the main goal for the industry, not only driven by fuel prices, but now in the environmental impact. Opportunities continue to exist for addressing aviation emissions through further air traffic management and operational measures, but clearly not sufficient to push the ambitious 50% reduction by Therefore, aviation industry will continue to pursue a range of opportunities in new technology, such as new aircraft design and biofuels as to meet these emission reduction targets Fig. 5. Figure 5: Emissions Reduction Roadmap The Group on International Aviation and Climate Change (GIACC), formed at ICAO 36 th assembly, has recommended the following potential areas of development and investments to Contracting States defined as follows [19]: 1. Investment in new technologies Measures in this category may include purchase of new aircraft, retrofitting and upgrade improvements on existing aircraft, new designs in aircraft/engines, fuel efficiency standards and alternative fuels. 2. Development of efficient operations These measures include minimizing weight, improving load factors, reducing speed, optimizing maintenance schedules, and tailoring aircraft selection to use on particular routes or services. 3. Investment on effective infrastructure These measures mean more efficient air traffic management planning, ground operations, terminal operations (departure and arrivals), en-route operations, airspace design and usage, and air navigation capabilities are measures with potential for relatively short to medium-term gains although the scale of potential relative gains is low to medium. In addition, more efficient planning and use of airport capacities, construction of additional runways and enhanced terminal facilities, and clean fuel operated ground support equipment to be implemented in the short to mediumterm. 4. Positive economic measures These measures include voluntary carbon offsetting, emissions trading schemes (CORSIA, Market Based Measures), emissions charges and positive economic incentives. Measures in this category have potential for achieving gains in term of reductions in net emissions. 5. Regulatory and others Measures that include regulatory enforcements on carbon emissions reduction (i.e. aircraft movement caps/slot management) and other initiatives such as enhanced weather forecasting, transparent carbon reporting and education/training programs.

6 In 2010, as part of its 37 th General Assembly, ICAO set out a fuel efficiency goal to 2% per year (above the former 1.5%) and reinforced the carbon-neutral growth as an aspirational goal from It also decided to develop an aircraft certification standard for CO 2 emissions, similar to the existing standards for noise and engine emissions (nitrogen oxides, carbon monoxide, unburned hydrocarbons and smoke). With this ICAO would foster development and use of fuelefficient technologies and designs by aircraft and engine manufacturers. With ICAO s engagement, all levels of the industry and States were finally committed with the new emissions reductions targets the focus turned significantly to fuel efficiency programs. The 39th session of the ICAO Full General Assembly convened in Montreal for a two-week session starting September 27 th 2016 to discuss the future of aviation emissions. Over 190 countries were represented in the Assembly to decide the basis for the implementation of CORSIA the Carbon Offsetting and Reduction Scheme for International Aviation. The fact that Paris Agreement (also held in 2016) did not mention aviation explicitly and that another General Assembly would only happen in 2019 made ICAO s 39 th General Assembly even more important as called global attention as Member States were discussing a first-ever global agreement that would limit and maybe reverse growth in CO 2 emissions from airlines. The main challenge was to agree on a mechanism that would allow the sector to continue its growth worldwide (especially in developing countries) and, at the same time, meet ICAO s carbon neutral growth target to clean up its environmental footprint. The rationale behind initial proposal for CORSIA was: 1. Phase Implementation Approach. To address special circumstances and capabilities of States where Pilot Phase from 2021 to/including 2023 and First Phase from 2024 to/including Participation in the two phases would voluntary. The difference between the two phases: pilot phase would have two options to determine the basis for the offsetting requirement of aircraft operator: either emissions covered by the CORSIA in a given year (i.e. 2021; 2022 and 2023), or emissions covered in a single year of The Second Phase, starting in 2027 would apply to all States with RTK (Revenue Tone per Kilometer) above 0.5% of total RTKs. 2. Route Based Approach. Coverage on the basis of routes between States to minimize distortions between aircraft operators on the same routes and provide equal treatment. A route is covered by the scheme if both States connecting the route are participating in the scheme and a route is not included in the scheme if one or both States connecting the route are not participating in the scheme. The proposed mechanism had a provision for the adoption of alternative biofuels but in the short-term airlines could start buying up carbon credits and increasingly switch to sustainable low carbon synthetic jet fuels. Improvements in aircraft technology and operations to reduce fuel consumption will determine the level of reliance on the scheme, assuming that the aviation industry will continue to grow. According to a study from the Stockholm Environment Institute (SEI), carbon offset could achieve 70-90% of ICAO s projected demand for emission reductions ( Gt CO 2e) with aviation biofuels contributing average 5% of those emission reductions ( Gt CO 2e) between if produced sustainably according to international standards for certification of sustainability. [33]. V. SUSTAINABLE AVIATION BIOFUELS One of the most important technologies for aviation industry to meet its environmental targets and reduce emissions is aviation biofuels. Since 2008 a number of test flights have taken place. Since then 5 pathways have been certified according ASTM [34]: FT-SPK (Fischer-Tropsch Synthetic Paraffinic Kerosene) in Converts syngas into jet fuel was approved by ASTM (D7566) and UK MOD DefStan (91-91). Can be blended up to 50% with fossil jet fuel. HEFA (Hydroprocessed Fatty Acid Esters and Free Fatty Acid) pathway was approved in 2011 to be blended at 50% rate with jet fuel. Converts natural oils from lipids to hydrocarbons by treating the oil with hydrogen to remove oxygen and other molecules. HFS-SIP, approved in 2014 up to a 10% blend, entails the fermentation of sugars into a hydrocarbon molecule using modified yeasts. The existing approved process produces a C15 hydrocarbon molecule called farnesene. FT-SPK/A, approved in 2015 up to 50% blend, uses the FT synthesis process plus the alkylation of light aromatics (primarily benzene) to create a hydrocarbon blend that includes aromatic compounds. ATJ-SPK, approved in 2016 up to 30% blend, a yeast biocatalyst converts sugars (carbohydrates) to isobutanol, As of mid-2016, over 1600 flights have been operated using different blends of biofuels with conventional kerosene. These flights have demonstrated that alternative fuels are safe and technically sound and can reduce overall carbon footprint by average 60-80% over its full lifecycle, depending on the pathway and feedstock used. Aviation drop-in biofuels are blended directly with petroleum jet fuel and are expected to meet or exceed performance standards of fossil fuels with no change to airplanes, engines and fueling infrastructure. Aviation Biofuels are seen as key long-term technology for decarbonizing aviation and that is demonstrated by the strong and increasing interest and support from airlines. In 2016 several airlines signed offtake agreements to purchase biofuels: Virgin Atlantic and LanzaTech Partnership Produces Renewable Jet Fuel from Industrial Waste Gas. JetBlue Announces 10-Year, 330 M Gallon Offtake Agreement with SG Preston.

7 KLM, AltAir, and SkyNRG Sign Three Year Offtake Agreement for Alternative Jet Fuel Supply. Lufthansa Signs Heads of Agreement with and Gevo, Inc. for Alternative Jet Fuel Supply. United Airlines announced a partnership with biofuel company Fulcrum BioEnergy to invest in future commercial-scale aviation biofuel plants. There are other relevant initiatives in US, Europe and elsewhere with participation of major airlines, Government and biofuels producers with the goal to speed up the production and use of aviation biofuels. Technological breakthroughs in biological improvements, chemistry and the development of systematic approaches for the production of aviation biofuels has driven the costs down, according to market estimates, from around $30/gallon in 2009 to $3/gallon in 2015, and that was achieved without direct incentives from Governments. One of the best examples of a systematic approach to the production of aviation biofuels is the initiative led by Boeing, Masdar Institute and Etihad Airways (Sustainable Bioenergy Research Consortium SBRC that also includes Takreer, Safran and General Electric) to produce both aviation biofuels and food using halophytes irrigated with seawater (Fig.6). Boeing is an important stakeholder in aviation biofuels, working as a catalyst for the development of the industry several countries. In Brazil, Boeing and Embraer created the Joint Research Center for Sustainable Aviation Biofuels to fund research and develop gap-filling technology portfolio of projects that will contribute to the kick-start of the industry in a sustainable way, creating conditions for local communities to also benefit from opportunities and improve living conditions. The partnership between Boeing and Embraer was also responsible for the publication of the book Roadmap for Sustainable Aviation in Brazil (together with FAPESP Sao Paulo based research funding agency). The book, a landmark publication in Brazil, identified opportunities and gaps for the development of promising feedstock and conversion technologies (Fig. 7) that were more likely to benefit from Brazilian abundant natural resources and research capabilities for the production of sustainable aviation biofuels. Figure.7 Feedstock Costs x Technical Efforts in Brazil. Source: Flightpath to Aviation Biofuels in Brazil Action Plan VI AIRCRAFT DESIGN ASPECTS Figure 6: integrated seawater, energy and agriculture. (Source: Masdar Institute) These "super plants" could lead to a breakthrough in Biofuels as seawater and sand once considered a weakness could become, in fact, the strength of the project. According to Masdar Institute, the salicornia plant (the super plant ) is a salt-tolerant halophyte, with a unique internal mechanism that allows it to grow in seawater. Its seeds contain plant oils that can be turned into jet fuel. The Consortium has recently began construction of its integrated seawater, energy and agriculture facility at Masdar City, the world s first bioenergy pilot project to use desert land irrigated by seawater to produce both aviation biofuels and food. The 20,000 square-meter bioenergy pilot facility will include saltwater aquaculture ponds where fish and shrimp will be grown. Water from the ponds, including nutrient-rich waste produced by these fish, will be used to irrigate and fertilize salt-tolerant halophyte plants that will then be harvested and turned into aviation biofuel and other products [32]. Historically, the development of aviation has always been driven by fuel efficiency (fuel burn per seat), and over the last 50 years the fuel burn (and also the carbon emissions) per passenger kilometer has been reduced by over 70%. Fuel is actually the most important single cost element for airline operators; and the high and strongly volatile oil prices of the last years have even more increased their need for more fuelefficient aircraft. In addition, an aircraft certification standard limiting carbon emissions is currently under development at ICAO and intended to drive forward the development and encourage the use of more low-emissions aircraft. The fuel efficiency of civil aviation can be improved by a variety of means including the incorporation into airplanes of new technologies, operations techniques and air traffic management. According to IPCC [20], technology developments might offer a 20% improvement in fuel efficiency over 1997 levels. It is noticeable that over the past 40 years, since the first generation of jet transport aircraft, fuel efficiency has improved 82% (Fig. 8), considering the 4 th generation of jet engines and airplanes made of CFRP (Carbon-fiber Reinforced Polymer).

8 VIII. CONCLUSIONS Figure 8 : Fuel efficiency gain since the early jet age (Source: IATA) The development of new operational procedures and techniques are relevant, but limited to the current technological limitations. Fuel conservation programs are widely used by airlines and improvements are observed on the magnitude of 5% to 10% at most. This represents a significant improvement with relatively small amounts of investment and airlines are constantly encouraged to optimize their operations on fuel conservation initiatives. However, the first of the four pillars (new technologies) is considered nowadays as the main potential contributor for achieving the desired ICAO objectives in emission reduction. Its achievement strongly depends on the development and implementation of new technologies by aircraft, engine and equipment manufacturers, using higher fidelity aircraft design tools. The main areas have direct impact on fuel efficiency are envisioned to be airframe (aerodynamics, structures, equipment systems and new configurations) and engines technologies. Today, a large number of individual technologies are under consideration for implementation in future aircraft and engines. For example, a study conducted in 2013 by IATA [19], the German Aerospace Center (DLR) and the Aircraft System and Design Laboratory (ASDL) of the Georgia Institute of Technology (Georgia Tech) launched the Technology Roadmap for Environmentally Sustainable Aviation (TERESA) [21]. The objective was to quantify the expected benefits of the implementation of individual technologies in an operational framework, considering a typical world fleet. Current NASA s readiness levels [22] are considered to estimate the availability of each proposed technology. It is worth to mention that environmental benefits of new technologies (through a better fuel efficiency and thus lower carbon emissions) will become effective through airline fleet modernization and, to a minor degree, retrofits to in-service aircraft. There is an underlying challenge to select the appropriate technologies as this selection are driven by uncertain factors such as their current development status, benefits, risk and their research and development costs. In summary, aircraft design techniques under the environmental perspective became significantly more relevant throughout the last decade, driven by the industry commitment on emissions reductions set by ICAO goals. The inclusion of fuel efficiency focus on the design framework is a key parameter on the next decade. Electric vehicles will become a considerable part of the road vehicle fleet in the coming decades, causing a deep reduction in total transportation emission levels. In 2050 under the most pessimistic scenario for aviation, when 100% of road vehicles would be electric (with maximum efficiency 80%) and no aviation biofuels are used, the proportion of transport CO 2 emissions due to aviation would be 46.7%, 3.3 times greater than the 2005 levels (no EVs and no biofuels). Introduction of biofuels into commercial aviation would reduce up to 9% of ICAO s projected emission reduction for the period of , and mitigate part of the relative increase in CO 2 emissions due to the introduction of electrical road vehicles. The remaining gap for achieving full ICAO and aviation industry targets could be filled with the implementation of a global carbon offset mechanism that will require commitment from member states and industry. REFERENCES [1] FAA, Aviation Emissions, Impacts & Mitigation: A Primer, Federal Aviation Administration, Office of Environment and Energy, January, [2] International Civil Aviation Organization, ICAO (2009). Group on International Aviation and Climate Change (GIACC) Report, Montreal, Canada, June [3] European Comission, Flightpah 2050: Europe s Vision for Aviation, Report of High Level Group on Aviation Research, European Union, [4] Electric Power Research Institute, Environmental Assessment of a Full Electric Transportation Portfolio, Report No , Electrical Power Research Institute, California, Sepetember, [5] Hartman et al., Observations: Atmosphere and Surface, Tech. Report, Intergovernmental Panel on Climate Change, Chapter 2, [6] European Commission, Climate change: Commission proposes bringing air transport into EU Emissions Trading Scheme, European Commission Press Release: Brussels, December [7] IEA, World Energy Outlook 2006, International Energy Agency, Paris, 596 pp., [8] A. Bannet, Can Aircraft Trails Affect Climate?, Nature, December Available: html [Accessed: March, 2015]. [9] N. Stern, The Economics of Climate Change: the Stern review, Cambridge University Press, January 2007, 712 pages.

9 [10] ICAO. Convention on International Civil Aviation Annex 16: Environmental Protection, Vol. II - Aircraft Engine Emissions Montreal, Canada. [11] IPPC, WG III Formulation of Response Option Strategies, Intergovernmental Panel on Climate Change (IPCC) First Assessment Report, Vol. III, [12] D. S. Lee, I. Köhler, E. Grobler, F. Rohrer, R. Sausen, L. Gallardo-Klenner, J. J. G. Olivier, and F. D. Dentener, Estimations of Global NOx Emissions and their Uncertainties, Atmos. Environ., 31, , [13] H. Hidalgo, and P. J. Crutzen, The Tropospheric and Stratospheric Composition Perturbed by NOx Emissions of High-altitude Aircraft, J. Geophys. Res., 82, , [14] C. E. Johnson, J. Henshaw, and G. McInnes, Impact of Aircraft and Surface Emissions of Nitrogen Oxides on Tropospheric Ozone and Global Warming, Nature, 355, 69 71, [15] U. Schumann, The Impact of Nitrogen Oxides Emissions from Aircraft upon the Atmosphere at Flight Altitudes Results from the AERONOX Project, Atmos. Environ., 31, , [16] M. Gauss1, I. S. A. Isaksen1, D. S. Lee2, and O. A. Søvde, Impact of Aircraft NOx Emissions on the Atmosphere Tradeoffs to Reduce the Impact, Atmos. Chem. Phys., 6, , [17] Metz, B., Davidson, O.R., Bosch, P.R., Dave, R., Meyer, L.A. (eds): Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, [18] The Intergovernmental Panel on Climate Change, IPCC (2007). Mitigation of Climate Change. Contribution of Working Group III to the Fourth Assessment Report of the IPCC. Cambridge University Press, UK, [19] International Civil Aviation Organization, ICAO (2009). Group on International Aviation and Climate Change (GIACC) Report, Montreal, Canada, June [20] International Air Transport Association, IATA (2013). Technology Roadmap. 4 th edition, June Montreal, Canada, [21] Nolte, P. et.al, Quantitative Assessment of Technology Impact on Aviation Fuel Efficiency, Air Transport Operation Symposium, Delft, June [22] Mankins, J. C. (2012). Technology Readiness Levels, A White Paper, Advanced Concept Office, Office of Space Access and Technology, NASA. [23] Royal Commission on Environmental Pollution, The Environmental Effects of Civil Aircraft in Flight, rcep.org, London, UK, Available: [Accessed July 2004]. [24] F. Collier, Overview of NASA s Environmental Responsible Aviation (ERA) Project: A NASA Aeronautics Project Focused on Midterm Environmental Goals, 48th AIAA Aerospace Sciences Meeting, Orlando, FL, [25] International Energy Agency, Global EV Outlook - Understanding the Electric Vehicle Landscape to 2020, Paris, April [26] The Boeing Company, Boeing 787 from the Ground up, Aero Magazine, fourth quarter, [27] Boeing Co., Current Market Outlook , Boeing Co., December, [28] Fulton, L. and Eads, G., IEA/SMP Model Documentation and Reference Case Projection, IEA, July [29] International Energy Agency, Global Energy Outlook, Paris, [30] Stansfeld, S. A. and Matheson, M. P., Noise pollution: non-auditory effects on health, British Medical Bulletin, Vol. 68, Issue 1, pp, , [31] Weiss, R., Noise Pollution Takes Toll on Health and Happiness, Washington Post, Tuesday, June 5, 2007 [32] Masdar: [33] SEI Study - Rob Bailis, Derik Broekhoff, and Carrie M. Lee, Supply and sustainability of carbon offsets and alternative fuels for international aviation [34] Caafi Commercial Aviation Alternative Fuels Initiative. BIOGRAPHY Jose Alexandre T.G. Fregnani Has the main responsibility to lead the Engineering research activities for Boeing Research & Technology in Brazil in the Airspace, Operations Efficiencies and Flight Sciences technologies, with emphasis in optimization of current operating practices of commercial airplanes. In his role also conducts internal research in the field of modeling and optimizing the operation of commercial airplanes mostly through computer simulations and analysis. Has more than twenty years of experience on Flight Operations domain working as Flight Operations/Performance Engineer and Airline Pilot at several airlines and renamed OEMs. Specialist in the following areas: fuel conservation, aircraft high and low

10 speed performance, weight and balance, aircraft performance monitoring, emissions, noise, PBN procedures design and Air Traffic Management. Onofre Andrade Has the main responsibility to lead the sustainable aviation biofuels research activities for Boeing Research & Technology in Brazil. In this role, he is responsible for coordinating research and managing all other biofuels related to biofuels, including the Joint Research Center for Sustainable Aviation Biofuels with Embraer. Before joining Boeing in 2013, Onofre Andrade worked as Sustainability Manager for Argos Energies in The Netherlands where he lived and worked for over a decade. Onofre is a specialist in the certification of sustainability of Biofuels.