Tools From CAAFI
The "Path to Alternative Jet Fuel Readiness" briefing document was developed by the CAAFI R&D Team to outline the process of fuel development, qualification and certification and the role of CAAFI in facilitating the process. It is intended for use by individuals and organizations interested in producing alternative fuels.
​
The "Path to Alternative Jet Fuel Readiness" document provides information on how to become involved with the aviation community, the testing and environmental evaluations required to show the fuel's suitability for aviation use, and how to best facilitate ASTM International certification for a new fuel.
​
The "Path to Alternative Jet Fuel Readiness" document also refers to several CAAFI communication tools designed to aid in the communication of both the necessary steps to be taken and the progress of alternative jet fuel projects:
The Path to Alternative Jet Fuel Readiness
Prescreening Guidance for Alternative Jet Fuels
The aviation industry’s evaluation and qualification process for synthesized jet fuel components, as detailed in ASTM D4054 and elsewhere, can involve four tiers of testing, two research reports, and three balloting junctions. This process can be resource-intensive, but ensures that any alternative fuel specification approved by the industry outlines the production of safe, fungible Sustainable Aviation Fuel (SAF) that is compliant with stakeholder demands arising from their insights into the need for such physical and fit-for-use properties. However, this process can span multiple years at significant cost to all parties involved, making mid-course fuel qualification corrections painful to prospective SAF developers. The extensiveness of this process has highlighted a need for early-stage, low volume, low cost, and rapid prescreening techniques outside the formal ASTM D4054 approval and evaluation process, especially those that relate to the assessment of jet engine combustor operability, which are among the most expensive testing requirements of the evaluation process. The Prescreening of Synthesized Hydrocarbons Intended for Candidates as Blending Components for Aviation Turbine Fuels document identifies prescreening methods that can provide early stage confidence to fuel developers on whether SAF formulations might encounter downstream challenges with the completion of the ASTM D4054 evaluation process.
​
These prescreening methods have been developed from learning acquired from the National Jet Fuels Combustion Program (NJFCP), JETSCREEN, prior industry approvals of SAF, and other associated SAF programs. These methods do not replace the ASTM D4054 evaluation process and its requirements. However, results from this prescreening should provide an early assessment of whether serious combustion issues could be encountered in the formal approval process. This could help SAF developers make early decisions on SAF composition or production processes that could help facilitate later approval, either for Fast-Track or Standard approvals (see ASTM D4054 Standard Practice).
The leadership of CAAFI needed a way to classify and track progress on research, certification, and demonstration activities. A variety of scales were in use by CAAFI organizations including TRL (Technology Readiness Level) used by industry, NASA, and the Air Force and Manufacturing Readiness Level (MRL) used by the Air Force and others. Originally, an Airbus CAAFI representative developed a special TRL scale for fuel development, but it was a mixture of research achievements and production development. The CAAFI leadership team wanted a new fuel development scale that would allow for parallel fuel research activities and certification activities, as well as clearly showing how to transition activities between the CAAFI R&D, Certification, and Business & Economics teams. Also, CAAFI desired to show how these new Fuel Readiness Levels (FRL) mapped to the TRL and MRL scales also in use.
​
The leaders of the CAAFI Certification and R&D teams developed the FRL table. It includes descriptions that are customized to fuel research and certification events and includes specific items of interest to CAAFI members, including required fuel quantities. Note that the fuel quantities listed are from CAAFI Certification guidelines, and the Air Force uses different fuel quantities in their military fuel certification process. Color coding used to show the transition points between the CAAFI R&D, Certification, and Business & Economics teams. The CAAFI teams operate with the realization that overlap will occur, with R&D leading FRL 1-5, Certification FRL 6-7, and Business & Economics FRL 8-9. Environment Team assessment requirements will also overlap with the FRL. Preliminary assignments of environmental touchpoints are reflected in steps 3 and 8. A more detailed list of environmental due diligence needs are described in CAAFI’s Environmental Progression.
​
CAAFI uses the FRL to help organize and track fuel development and the process of developing, certifying, and supplying alternative fuels to commercial aviation.
​
The FRL was endorsed at the United Nations' International Civil Aviation Organization (ICAO) Commercial Aviation Alternative Fuels (CAAF) meeting in Rio de Janeiro in November 2009. The outcomes of that meeting can be found here.
To facilitate the use of the FRL, a checklist of exit criteria (tasks that must be accomplished to move from one FRL level to the next) was developed by CAAFI in collaboration with the Air Force Research Laboratory.
ASTM D4054 was developed to provide alternative jet fuel producers with guidance regarding testing and property targets necessary to evaluate a candidate alternative jet fuel. The ASTM D4054 data and proposed specification properties investigated through the four-tier approach are then used as the basis for continued engagement with ASTM. The certification process requires fuel producers to iterate through the defined checkpoints, and if the fuel successfully passes, this process may result in the development of a proposed annex for incorporation into ASTM D7566 as a drop-in synthetic jet fuel.
​
Therefore, it is important to get prospective producers engaged with the testing community as early as possible. CAAFI's intent of creating this D4054 User's Guide is to provide an index of facilities that have:
​
-
demonstrated the technical capabilities necessary to perform the aviation fuel property testing required by D4054, and;
​
-
expressed an interest in performing those tests in the future.
​
We hope this helps prospective fuel producers locate resources to support testing of their fuels for ASTM approval.
​
This document is not static, and as with other CAAFI guidance material, we will continue to add helpful resources and information as the need is identified.
Feedstock Readiness Level
As a result of the implementation of the CAAFI Fuel Readiness Level, the CAAFI R&D team identified the need for a separate evaluation of feedstock readiness to complement the FRL. CAAFI therefore approached the US Department of Agriculture (USDA) to collaborate on the development of a Feedstock Readiness Level (FSRL), which was accomplished under a Memorandum of Agreement between USDA and the Federal Aviation Administration (FAA).
​
The Feedstock Readiness Level (FSRL) Tool is a companion to the CAAFI® Readiness Level (FRL) Tool. The FSRL Tool provides a means of tracking development and availability of the raw materials (or feedstocks) required to make alternative jet fuels. In detailing the steps necessary to establish feedstock production in the commercial sector, a complete supply chain systems context is implied. The FSRL Tool covers four components: (1) Production, (2) Market, (3) Policy - Program Support and Regulatory Compliance, and (4) Linkage to Conversion Processes. The FSRL Tool components parallel the FRL. This approach provides an integrated way to demonstrate the mutual requirements of feedstocks and conversion technologies.
​
As part of the Farm 2 Fly 2.0 Initiative (F2F2), CAAFI has established the F2F2 Feedstock Readiness Level Evaluations Repository, and is collecting evaluations of feedstock readiness levels for region/feedstock/process combinations. The Feedstock Readiness Level Tool is an Excel Workbook that contains an Introduction sheet providing instructions for completing an evaluation, an evaluation overview sheet for information relating to yield and potential scale of production, two evaluation checklists (one for crops and woody species and one for agriculture and forest residues—the user should choose the appropriate sheet), and a summary report template for the feedstock evaluated.
Examples of how to use the checklist can be found on the repository, which also contains a summary table of the evaluations. CAAFI welcomes evaluation submissions from researchers and other stakeholders.
Please contact us with any questions about the document or to submit completed evaluations.
Guidance for Selling Alternative Fuels to Airlines
CAAFI has published the “Guidance for Selling Alternative Fuels to Airlines” document to serve as a roadmap for potential producers and other supply-chain participants contemplating purchase agreements with airlines for non-petroleum-derived jet fuels. It outlines key steps and criteria for potential producers to engage with airlines and highlights how and when CAAFI can help. The report was co-authored by former CAAFI Business Team Leads Dr. Bruno Miller and John Heimlich in close consultation with the heads of Airline for America (A4A) member airline fuel management departments.
​
To assist producers and investors, the paper constitutes a central source of answers to the following questions:
​
-
Why are airlines interested in commercial-scale alternative jet fuel production?
-
What are the airlines' requirements for contemplating the purchase of alternative jet fuel?
-
What are airlines willing to do to help commercialize alternative jet fuel?
-
What does a "term sheet" look like?
-
What is the best way to engage with airlines?
-
How can CAAFI help?
​
In addition, it includes a matrix of CAAFI readiness tools with recommended avenues for commercial engagement at various stages of development. The readiness tools are key communication protocols to help airlines, producers, and other stakeholders to explicitly understand one another's progress levels, by providing visibility and transparency into the current and projected state of aviation alternative fuel development.
​
CAAFI expects to augment this guidance in the future with appendices including additional lessons-learned and non-proprietary details from actual commercialization success examples as they occur.
​
Finally, CAAFI also provides a link to IATA’s “Aviation Fuel Supply Model Agreement” to serve as an additional resource for consideration of streamlining the process of purchasing and selling jet fuel.
Environmental Readiness
The CAAFI Sustainability Team identified the need for a common understanding of environmental sustainability issues among the stakeholder community to facilitate understanding of environmental performance measures and engender confidence when entering off-take agreements for alternative jet fuels.
While there are growing concerns regarding environmental and other risks associated with petroleum-based jet fuel, which might be addressed through the development and deployment of alternative jet fuels, the development of a new industry for alternative fuels also has its risks and challenges. Central among these are sustainability issues, and as one of the key drivers for adoption of alternative fuels is environmental benefit, the environmental sustainability challenges of alternative fuels have come under intense scrutiny.
As the aviation community seeks to adapt to the changing energy landscape and facilitate the development and use of alternative jet fuels, the industry will need to ensure that the fuels into which it invests political and economic capital will provide the hoped-for benefits (environmental, economic, and social).
This document is intended to provide some common ground for discussing the environmental sustainability challenges associated with the development, deployment, and use of alternative jet fuels.
This document is a working document, which will be subject to revision and updates over time as deemed appropriate by the CAAFI Sustainability Team.
To facilitate evaluations of Fuel and Feedstock Readiness, the CAAFI Sustainability Team developed the Environmental Progression with input from a variety of organizations and stakeholders to provide guidance on when different environmental analyses might best be performed during the development of a new fuel production process.
For example, aspects of environmental sustainability that are potentially difficult to mitigate or are irreversible (e.g., land use conversion and biodiversity impacts or invasive species introduction) need to be evaluated prior to facility establishment or feedstock introduction. Some of these (e.g., invasive species risks and/or impacts) also need to be evaluated both during scale up and during operations.
Critical sustainability indicators such as GHG emissions may also be preliminarily evaluated prior to scale up (screening level GHG life cycle analysis (LCA)). Other evaluations may be done during scale up (e.g., study level GHG LCA). Other measures may not be possible until a commercial facility is in development (e.g., acquisition of permits) or established (e.g., compliance with permits, comprehensive GHG LCA).
In many cases these evaluations should also be repeated over the course of development and/or process refinement, as the evaluation results may change substantially due to changes (including possible improvements) over time.
​
This tool parallels the Fuel and Feedstock Readiness Level tools and can be used in conjunction with them to better understand the developmental status of a fuel and/or feedstock.