Researchers in Florida are continuing to study an oilseed that could be used as aviation jet fuel.
After over a decade of research, agronomists and researchers at UF/IFAS are continuing to assess the performance of carinata, basing their research at the North Florida Research and Education center located in Quincy, Florida.
Brassica Carinata, commonly known as Ethiopian mustard or carinata, cannot be eaten but is an oilseed used in renewable fuels and co-products. Carinata contains unique properties, particularly its high contents of erucic and linolenic acid in extracted oil. Although not safe for consumption, the high contents of non-food oil make it suitable for the production of drop-in sustainable aviation fuel.
Drop-in aviation fuels, known for their sustainability, are a synthetic alternative to petroleum-based fuels that can be used in existing aircraft and fuel infrastructure without any modifications.
“The reason why this seed is so important is because it is high in non-edible oil, making it a great option for aviation fuel and renewable energy. This way, we can move away from fossil fuel and petroleum-based fuel,” said Sheeja George, project manager and agricultural scientist at the UF/IFAS North Florida Research and Education Center.
There are two main reasons why this crop is so attention-grabbing towards the environment and also the economy; it serves as a resilient winter cover crop, and it is an oil that can be decoupled from food systems.
Oil production significantly impacts food systems by providing the energy needed to power farm machinery, produce fertilizers, transport food across long distances and operate irrigation systems; fluctuations in oil prices can directly affect food prices and availability due to its vital role in modern agriculture and food distribution. In today’s society, a large portion of the food system relies on petroleum products to function effectively.
An example of a consumable oil that is also used as fuel is corn ethanol. Corn ethanol is ethanol produced from corn biomass and is the main source of ethanol fuel in the United States, mandated to be blended with gasoline in the Renewable Fuel Standard.
“As the price of oil or gasoline increases, then the value of selling corn as fuel increases as well,” said Dylan Rigsby, research coordinator of the carinata team. “If you can sell your corn as fuel instead of as food, then that will lead to an impact towards food systems.”
Second, one of its other benefits is working as a winter cover crop. When planting carinata as a winter crop, it can increase farmer revenue and provide ecosystem benefits to the plot where it grows. Carinata suppresses weeds, improves soil fertility by adding organic matter to the soil and provides a food source for pollinators. Sowing carinata in the winter may help retain soil moisture and reduce soil erosion.
In studies conducted by UF/IFAS, carinata has shown significant promise for southeastern producers by providing additional cash flow and cover crop benefits. These same studies have shown that double cropping with winter carinata is more profitable than producing a single crop per year. Although carinata can only be grown every third year in the same field due to the increased probability of disease pressure if grown back-to-back, it has been shown to collaborate well in fields that usually grow corn, cotton, peanut or soybean.
Farmers in the South East of the United States, specifically in the states of Georgia, Florida and Alabama, are considered great candidates for the growth of carinata as a winter cover crop.
The process of growing and harvesting carinata usually starts in the months of November or December, depending on the state. From planting to harvesting, the crop usually grows within 180 days. Once the crop is mature, usually around the month of April or May, the seed is harvested and the rest of the crop is left in the field. The seed then proceeds to be taken into a crush facility, where the oil is extracted from it. After this procedure, the oil undergoes various certification processes before being approved. Through these processes, carinata can be converted into aviation fuel, renewable diesel, among other sustainable forms of fuel.
“Carinata seeds typically contain about 40% oil by weight,” said Ramdeo Seepaul, assistant research scientist in the Agronomy Department. “With about 2,000 pounds of seeds per acre, this would translate to about 108 gallons of oil per acre. After refining the oil, about a third of it can be used for sustainable aviation fuel.”
The compost that remains after extracting the oil is also used, as new studies show that it is a meal high in protein that can be used as cattle feed.
“There are by-products from when the seed oil is converted to fuel, such as a high-protein meal which can be used as animal feed,” Seepaul said. “This further enhances the sustainability of the production system of carinata.”
When it comes to the adoption of carinata, the integration of the seed has been slow in Florida’s agricultural sector.
“It is a small seed, so the things that you need in order to harvest it are different from what you would use for a large seed,” George said. “ It is also a crop that takes its time to grow as of now, so farmers don’t want it to interfere with their next crop.”
George mentioned that it is a very promising crop, and suggested that with more research, they would aim to reduce the time it takes for the crop to mature in order to better improve the delays the harvesting might cause.
“One of the biggest factors that has surprised us with carinata over the years is when they undergo extreme freeze events,” George said. “We get freeze events every once in a while down here in Florida, and although the plant looks dead and bleached, it always finds a way to green up again and it comes back with full force.”
Several new varieties of carinata have also been developed over the years in the Southeastern part of the United States. These new varieties are high-yielding and produce more oil, which in turn provides a boost to the production of biofuel.
The carinata project, although initiated at the University of Florida, has also expanded to other public research facilities, such as the University of Georgia, North Carolina State University, Auburn University, the agricultural research services at the United States Department of Agriculture National Institute of Food and Agriculture, among others.
Even after more than a decade of research, carinata still faces some major obstacles in its production that is inhibiting its expansion.
Although there is demand for sustainable aviation fuel, policies have not caught up to support purpose-grown non-food oilseed feedstock like carinata. Even though there is momentum surrounding sustainability and reducing greenhouse gas emissions, the feedstocks are still bound to commercial ties and are still under research. When farmers decide to grow a crop such as carinata, they are exposed to financial risks, which can ultimately slow down the growth rate of the seed.
“Carinata is just one example of a bioenergy solution,” Rigsby said. “By creating an alliance with other types of bioenergy solutions, it could further create a movement to push for policy, therefore being beneficial for bioenergy all together.”
Economics play a big setback in the adoption of carinata.
“These crops, like any other commodity, go through high and low variations of prices,” George said. “Despite there being a big demand for sustainable aviation fuel in the United States, unless there is good and mature policy support, the economics are not going to play out.”
To facilitate adoption, researchers also mention that partnership is an area that needs observation. Partnerships face challenges around trust, protecting sensitive data and balancing public-private interests, requiring control systems and clear communication.
“At UF, we are working to address these challenges with the various projects we’re involved in, mainly through outreach and educating our producers,” Seepaul said. “This will hopefully make farmers see carinata’s potential as a winter crop.”
