As the world transitions toward a low-carbon energy future, biomass and waste-to-energy solutions are poised to meet the growing demand for Sustainable Aviation Fuel (SAF) and Low Carbon Aviation Fuel (LCAF). These solutions can play a significant role in meeting broader energy demands and reaching decarbonization goals. By leveraging waste materials and biomass feedstocks to generate SAF, we can accelerate the energy transition toward a cleaner and more sustainable aviation future.
Technologies that utilize biomass can help address the limitations of other renewable energy sources. While solar and wind power remain important components of the renewable energy mix, they have significant downsides; both require expansive infrastructure and land development which disrupts the surrounding ecosystem, and they can only produce energy intermittently since they are limited by weather conditions when not paired with batteries. Biomass and waste-to-energy solutions can help us solve these issues and beyond.
Waste-to-energy conversion technologies can produce high volumes of SAF and LCAF that can help decarbonize the aviation sector. Worldwide production of SAF only accounts for 0.1% of the SAF needed to meet global decarbonization goals. With this in mind, we must focus today on what technologies and products can pave the way for a greener tomorrow, and that includes increasing biomass feedstocks and associated pathways for SAF production.
Why does SAF Matter?
SAF burns more cleanly in aircraft engines compared to fossil fuels because of its unique composition, therefore reducing aircraft emissions. The International Air Transport Association (IATA) estimates that widespread use of SAF could lead to a 65% reduction in aviation emissions. This is a significant path to meet the most recent U.N. Paris agreement net-zero goals by 2050. Additionally, SAF production can lead to economic development opportunities and a symbiotic relationship between the agriculture and aviation sectors.
Domestic production of SAF is currently achieved using a mixture of food oils, including soybean, canola, corn oil and animal fats. However, the availability of these feedstocks is finite. Nearly 100% of cooking oil and animal fats will be in use well before 2027. To meet SAF production goals, it is imperitive to have a consistent, reliable feedstock pool.
Fortunately, there is an abundance of byproduct from the poultry industry in the U.S., and using chicken manure as a feedstock to produce SAF is advantageous for several reasons. First, it does not threaten national food supply or compete with agricultural needs. When we rely on vegetable oils and other food byproducts for feedstock, it becomes necessary to grow more crops that will be used solely for renewable energy generation. However, this practice results in the loss of valuable farmland that would otherwise be used to grow crops for food. Second, cost-effective handling and processing of animal waste is one of the many challenges farmers face. Raw animal manure can be rich in phosphorus and nitrogen and can have negative environmental effects when used in an uncontrolled manner. Dryer animal manures, such as poultry and turkey litter, have the distinct advantage of low cost transportation to offsite SAF or LCAF production facilities.
In a recent article, the IATA Director General Willie Walsh commented on the need for additional feedstocks and SAF pathways. When asked why the airline industry was not moving faster on the issue, he said, “The willingness of airlines to use SAF is definitely not the issue. As I have said, every drop of SAF ever produced has been purchased and used. The problem is insufficient production capacity to meet demand.” He went on to extoll the need to increase the number of ways we produce SAF and diversify feedstocks. Walsh is hopeful that state and local government will be some of the first to seize the moment, since increasing SAF production would create more jobs and stimulate the economy.
Chicken Litter and Producing SAF
There are more than 14 million tons of chicken litter produced in the U.S. each year according to the USDA. Each of CleanBay’s bioconversion facilities can recycle 30,000+ tons of chicken litter annually through an anaerobic digestion process to create biomethane and a natural controlled-release fertilizer. The biomethane can then be upgraded into SAF at the back end of the process using a conversion method called Fischer-Tropsch (FT).
FT is a chemical process that converts feedstocks with carbon into liquid hydrocarbon. Biogas is particularly suited to produce SAF through intermediate FT unit operations such as Water Gas Shift, steam reforming and catalyzed synthesis. Since the liquid produced during FT contains hydrocarbons with varying molecular weights, producers use fractional distillation to yield a product with the best boiling range for aviation fuel. After a refined SAF is produced and blended with some conventional jet fuel, it is immediately ready for use in various types of aircraft. Commercial, military and smaller aircraft can use SAF and LCAF as conventional jet fuel without needing any engine modifications.
The main impediment to SAF adoption is not reluctance from airlines, but the lack of production capacity and insufficient feedstock pathways. The aviation industry’s increasing commitment to decarbonization, alongside a growing demand for air travel, necessitates the development and utilization of SAF derived from additional renewable feedstocks like chicken manure. CleanBay is committed to leveraging current technologies and partnerships to expand the production of advanced fuel products like SAF. Together with industry stakeholders, we can make significant strides towards a cleaner, more sustainable energy landscape.