Sustainable aviation fuel development: case study in Indonesia

The usage of fossil fuel in aviation contributes to 2% of CO2 emission globally. Though the industry keeps improving the efficiency of the aircraft, the increase in activity offset this improvement. The usage of sustainable aviation fuel (SAF) may become a potential option in order to reduce emissions. SAF immediate compatibility and low emission become the main attraction for its usage. Indonesia in order to fulfill its NZE commitment is currently developing its own biofuel. This study’s objective is to obtain information on SAF or biofuel development in Indonesia by discussion with experts and stakeholders related to aviation and fuel development. By conducting this study it is known that the development of biofuel in Indonesia has successfully resulted in two products, J2.0 and J2.4, biofuel developed based on palm oil. Though these fuels have been certified domestically, their implementation still faces several issues, such as the sustainability aspect related to the CORSIA scheme, the production volume and availability, and potential price surge. Therefore through this study several recommendations are presented in the hope to accelerate the implementation. Although the direction of SAF development in Indonesia is through the usage of Palm oil as its main feedstock, Indonesia also has used cooking oil (UCO) and Sugarcane as potential feedstock to be explored. The development and implementation for these feedstock into SAF is necessary as a possible solution for reducing the greenhouse gas emission, therefore a support through financial, technological, and regulation means are necessary to be provided by all stakeholders.


Introduction
Heavy usage of fossil fuel nowadays such as in the transportation sector contributes heavily to global warming [1].The usage of this fuel increases the contain of several gasses, such as Carbon dioxide (CO 2 ), Methane (NH 4 ), Sulfur dioxide (SO 2 ), and Nitrogen dioxide (NO 2 ) [2].Human activity contributes to 94 percent of carbon emission through the usage of natural resources.It is also estimated that the emissions produced in aviation affect the health of people around the globe [3].The CO2 emission becomes the major contributor due to its quantity and the duration its resides in the atmosphere [4].In 2018, the transportation sector was the second largest contributor to greenhouse gas emissions in Indonesia, namely 26.4 percent or around 157,325 Gigagrams CO2 equivalent.In the past decade, there has been a notable annual increment of 7.88 percent on average [5].The emission is reduced for several years due to the COVID-19, but the number will soon bounce back to its pre-pandemic condition [6].
Indonesia, along with many countries, try to address the emission produced by the aviation Industry.At COP26 in Glasgow, Scotland (Oct-Nov 2021), it was emphasized by Indonesia that emissions reduction should be achieved through increased utilization of new and renewable energy sources, including the use of biofuels.This is also aligned with the Republic of Indonesia Minister of Transportation's Decree No. KP. 201 of 2013 on the Determination of the National Action Plan for Greenhouse Gas Emission Reduction in the Transportation Sector and the greenhouse gas inventory in the transportation sector from 2010 to 2020, which states that the initiative to use biofuels in the transport category of air transportation is in accordance with the ICAO Guideline, with a 3% implementation pilot conducted from 2018 to 2020.In November 2022, G20 Summit in Bali was held and one of the outcomes of the summit is a declaration document called the G20 Bali Leaders Declaration, in which G20 member countries committed to reducing environmental impacts by changing unsustainable consumption of energy [7].
Biofuels, in this case the Sustainable Aviation Fuel (SAF), become one of the potential candidates for reducing the aviation sector's climate impact [8].As an agricultural country, Indonesia has many potential feedstock as the ingredient for its SAF.However, for the producer to provide the necessary quantity, the production may compromise with the sustainability aspect such as the land use change, such as the case in Indonesia's choice of Palm Oil as the SAF feedstock.Therefore in order to obtain insight for the further development of an ICAO Acceptable SAF, the understanding for the development of SAF in Indonesia is necessary.SAF in Indonesia is a complex study with aspects consisting of regulation, technological limitation, availability of feed stock, political and economical aspects.

Method
The method of this research is a descriptive method, which elaborates the condition supported by the data obtained.The data was obtained by deep interview and discussion with experts in the environmental aspect in Air Transport in the Ministry of Transportation of Republic Indonesia, experts in the Ministry of Energy and Mineral Resources of Republic of Indonesia.Other than the discussion and interview, data is also obtained through regulation, article, research paper, and other literature.Regulations pertaining to SAF are identified, and the potential development of SAF feedstock is expounded.Suggestions and recommendations are formulated by establishing connections between the current SAF development, local regulations, and the available resources for SAF production in Indonesia.

SAF development
Indonesia aims to achieve Net Zero Emission by 2060 or earlier.This is reinforced by the President's statement at the 21st Conference of the Parties (COP) of the United Nations Framework Convention on Climate Change (UNFCCC) in Paris (Nov-Dec 2015), where Indonesia targeted a 29% reduction in greenhouse gas (GHG) emissions (with its own capabilities) or a 41% reduction (with international assistance) by 2030.
3.1.1.Sustainability of SAF.SAF became the main option in facing the emission issue due to its versatility.One advantage of SAF is its similarity to conventional fuel, so if a processed feedstock meets the ICAO criteria based on conversion methods following the standards of the American Standard Testing and Material (ASTM International), the resulting fuel can be used in aircraft directly without any modifications to the aircraft structure or engine.
ICAO, as the international aviation governing body, states that in order for a biofuel or bio-aviation fuel to be classified as sustainable aviation fuel (SAF), a Life Cycle Assessment (LCA) is necessary to determine the emissions of the product throughout its life cycle.ICAO has approved nine conversion methods for producing SAF, including examples of feedstocks such as palm oil, animal fat, grease, and used cooking oil.by Indonesia minimum should be 2% by 2016, 3% by 2020, and 5% by 2025 [9].Despite the target in the Regulation, the progress of development of SAF in Indonesia faces some challenges.Biofuel mixture developed in Indonesia currently only resulted in a 2.0 % and 2.4% mixture even though the mixture target is 3% by 2020.These fuels are produced in the form of J2.0 and J2.4 fuel respectively, produced by Pertamina in PT.Kilang Pertamina Internasional in Cilacap Refinery.

Regulation in Indonesia related to SAF
Indonesia's Government has issued several regulations to emphasize its commitment for the NZE target.The regulations are issued through several levels of government organization, from Presidential Regulation, Governmental Regulation, Ministerial Regulation, and many others.Table 1 shows several regulations regarding the usage of renewable energy and biofuel.Mixture target of Primary Energy Source: 1.In 2025 renewable energy will contribute at least 23% and 31% in 2050.2. In 2025 the contribution of crude oil will be less than 25% and less than 20% in 2050.3.In 2025, the contribution of coal will be less than 30% and in 2050 will be less than 25%.4. In 2025, the contribution of natural gas will be less than 22% and in 2050 will be less than 24%.As the world's largest palm oil producer, Indonesia possesses significant potential for the processing and marketing of palm oil-derived products, including palm kernel oil.Palm kernel oil can serve as a readily available feedstock for biofuels and sustainable aviation fuels.Understanding the potential production of palm kernel oil as SAF necessitates an examination of its production trends over years, as depicted in Figure 1.Due to the large quantity of palm oil produced in Indonesia, The biofuel developed by Pertamina is made from palm kernel oil as previously mentioned.This J2.4 biofuel has been tested in 2021 by using CN-235 aircraft owned by the Indonesian Air Force.The decision to use palm oil is based on the abundance of the palm oil in Indonesia as one of the leading producers in the world [11].Although both of the biofuels have been certified by Indonesia's own Oil and Gas Testing Agency (LEMIGAS), their acceptance into the CORSIA scheme in ICAO may still be an issue.These biofuels have yet to get the SAF certification recognized by ICAO in order to be eligible for the CORSIA scheme, mainly due to the sustainability aspect of the fuel itself [12].The loss of the rainforest in Indonesia due to the land use change is significant, around 40 million ha of land [13].This issue became the main obstacle regarding the sustainability aspect in LCA for the recognition of J2.4 and J2.0.Conducting a more comprehensive review regarding LCA calculations may become one of the solutions, by considering that the previous LCA calculations by ICAO were based on default values.ICAO allows the producer or country to calculate the actual LCA by providing proper and necessary technical information by scientific procedure and tests [14].The authorized body responsible for calculating Actual LCA should be appointed to formulate emission reduction solutions for the product life cycle.This can be learned from Brazil, which also develops SAF based on corn, soy, and sugarcane, but has low emissions.The development of SAF from other sources such as used cooking oil should also be considered.
The development of bio-aviation fuel by Pertamina is also still constrained by the current limitations of the refinery, where the Cilacap refinery used for biofuel production is not dedicated solely to biofuel.The new Cilacap Phase 2 refinery is planned to be built to meet the 5% blend target by 2025, which has become a national strategic program coordinated by the Ministry of Energy and Mineral Resources.Though the Indonesian Government, Pertamina, Institut Teknologi Bandung, and Garuda Indonesia plan to conduct the next phase of the test by using commercial aircraft in 2023, the production volume capability still remains.The construction of the refinery requires support in the form of investment funds and cooperation.
Based on sources from Indonesia National Aircraft Carriers Association (INACA), it is predicted that there will be a 10% increase in fuel prices with a 5% biofuel blend.This prediction may hinder the usage of the biofuels/SAF even after the successful development and production.The Ministry of Energy and Mineral Resources and the Ministry of Transportation, as regulators, need to develop temporary incentive schemes to assist airlines in implementing SAF in the future.These incentive schemes can be provided not only to airlines but also to attract other producers or developers of SAF to further progress SAF development in Indonesia.

Used Cooking Oil.
Heavy usage and production of Palm oil Indonesia for Food usage resulted in the abundance of Used Cooking Oil (UCO).The usage of UCO as feedstock of SAF is already known among SAF Producers.NESTE, one of SAF Producer from Finland is currently producing an ICAO approved SAF which also complies with CORSIA Scheme using UCO as feedstock.Currently one of NESTE's refineries is the newly finished refinery located in Singapore with production capacity of 1.3 million tonnes annually [14].This refinery is producing SAF with UCO as one of its feedstock.
Press release of the Ministry of Energy and Mineral Resources in 2020 mentioned that in the year of 2019, Indonesia consumed 16.2 million kilo liters (KL) [15].Despite the potential of UCO as the more sustainable alternative for SAF feedstock, it has issues that need to be addressed before it becomes feasible.The two main issues of UCO as feedstock is the collecting mechanism and the export attractiveness.Out of 16.2 million KL, 6.46-9.72 million KL were produced and only 3 million KL of UCO were successfully collected [14].From those quantities, 2.4 million KL were recycled to be reused for cooking and exported.Therefore in order for the UCO to be considered, the availability of UCO needs to be solved first.
Regulation or policy that can boost the appeal for UCO to be sold or used domestically need to be introduced.By introducing this policy, the distributor of UCO then will shift their customer from export to domestic companies instead.However, this policy will need to be accompanied by incentive and numerous benefits and mandates, which will also result in mixed reaction.

3.3.3.
Sugarcane.Sugarcane is a potential feedstock for SAF through its derivative of sugar and alcohol.The two derivatives are enlisted in the feedstock and conversion process of SAF production based on ASTM D7566 and D1655.The development of SAF is not yet commercialized and requires an investment for its development for production in industrial scale.The potential of sugarcane as the feedstock is shown from the production quantity, as shown in Figure 2. Indonesia also has UCO and Sugarcane as potential feedstock to be explored, though there are some challenges that need to be addressed first for them to be considered.The development and implementation for these feedstocks into biofuels or even SAF in Indonesia is necessary as a possible solution for reducing the greenhouse gas emission, therefore a support through financial, technological, and regulation means are necessary to be provided by all stakeholders.

Suggestion
In order for the fuel to be successfully implemented, several actions may be required: a) Mapping of stakeholders involved in SAF development according to their respective focuses, such as Implementation in transportation, Research for alternative feedstocks, Biofuel industry towards SAF, potential scheme and participant in Investment, research and innovation for the further development.b) Encouraging the formulation of cooperation through MoUs and the establishment of task forces involving multi-stakeholders.c) Establishing an authorized institution or agency to calculate the Actual Life Cycle Emissions (LCA) at the national level.Therefore, Indonesia isn't necessarily required to use the default value provided by ICAO.d) Further exploration is needed regarding other potential sources for biofuel, such as used cooking oil since its abundance in Indonesia due to the extensive consumption of frying food.A proper regulation concerning the limitation of UCO export may be necessary to reinforce the availability of UCO domestically.e) Pertamina, with support from the Ministry of Energy and Mineral Resources, needs to develop a new refinery dedicated to producing SAF.Focus for the palm oil industry is also needed in order to provide the ample amount of material for the biofuel production.
f) As the prices of the SAF are possibly higher than the regular jet fuel, correct policies need to be formulated.This policy will address the increase in operating costs for the commercial implementation of SAF, in order to assist air transport operators in maintaining profitability.
Studies and research need to be conducted to determine suitable incentives.Currently, only biodiesel made from palm oil as feedstock has incentives.g) In addition to domestic bio-aviation fuel development, stakeholders need to coordinate and consider establishing cooperation with foreign SAF producers who have succeeded in producing and developing SAF.It is necessary to conduct benchmarking studies in countries that have succeeded and advanced in SAF development.
Indonesia.Development of SAF in Indonesia is pioneered by the Ministry of Transportation, Ministry of Energy and Mineral Resources, Pertamina and Institut Teknologi Bandung.This effort is enforced by the release of Ministerial Regulation of Ministry of Energy and Mineral Resources No 12 Year 2015, which states that the mixture target of SAF or Bioavtur, produced

Figure 2 .
Figure 2. Indonesian Sugarcane Production 2017-2021 Source: BPS-Statistics Indonesia [16] 4. Conclusion Development of SAF Indonesia, in order to fulfill the Commitment for NZE in 2060, Indonesia through the Ministries, State owned Companies, and University, has been started.Currently Indonesia through Pertamina and Institut Teknologi Bandung successfully developed Indonesia's own biofuel, the 2.0 percent mixture J2.0 and 2.4 percent mixture J2.4.Though currently these fuels face several obstacles in the form of the sustainability aspect, the volume production capability, and the inescapable threat of price surge compared to regular jet fuel, both of the fuels have been successfully certified by Lemigas.Moreover, a flight test has also been conducted through the usage of military aircraft owned by Indonesia Air Force in 2021, with the commercial aircraft flight test scheduled in 2023.Although currently the direction of SAF development in Indonesia is through the usage of Palm oil as its main feedstock, Indonesia also has UCO and Sugarcane as potential feedstock to be explored, though there are some challenges that need to be addressed first for them to be considered.The development and implementation for these feedstocks into biofuels or even SAF in Indonesia is necessary as a possible solution for reducing the greenhouse gas emission, therefore a support through financial, technological, and regulation means are necessary to be provided by all stakeholders.

Table 1 .
Regulation sample concerning renewable energy and biofuel in Indonesia

Tabel 2 .
The stages of minimum obligations for the utilization of pure bio oil as a blend in fossil fuels a a Ministerial Regulation of Ministry of Energy and Mineral Resources Number 12 Year 2015 3.3.Potential feedstock in Indonesia 3.3.1.Palm Oil.