Corn Is a Very Efficient Feedstock for Producing Sustainable Aviation Fuel

Ever wonder why Gevo is focused on corn for use as a feedstock to produce sustainable aviation fuel (SAF)?

First of all, consider the scale. If we’re going to move the dial on carbon intensity in a market like jet fuel, we need to have the volume to replace millions of gallons of fossil-based fuels. Corn is grown on around 93 million acres across our nation.

Second, it’s efficient: This corn has long been used to feed livestock (rather than being eaten by people directly), and that doesn’t stop when we use it to make fuel. We separate out the most valuable part of the corn, the protein in each kernel, to feed livestock, pets, and aquaculture. What’s left is the starch that is used as the feedstock for our process. It’s like getting twice the use out of every acre. Plus we save the corn oil for nutritional use as well.

Third, when you use climate-smart, sustainable agriculture across huge swaths of land, it makes a difference in terms of carbon intensity, and sequestering carbon in the soil.

Still wonder why corn makes sense as a feedstock for SAF? Have a look at these questions and answers:

Q. Is the corn used to make SAF and other renewable fuels the kind of corn we eat?

A. No. The corn used for Gevo’s SAF is industrial, field corn. It is not sweet corn that is found in cans or corn on the cob. For generations, it has been grown for the purpose of feeding animals, not humans. When Gevo uses this sustainably grown corn as a feedstock, the process creates approximately 5.7 pounds of high-value nutritional feed products for every gallon of fuel produced. In no way are our fuels taking food away from you or your family.

Q. How does Gevo put “food first”?

A. Gevo’s process is designed to deliver nutrition from every acre of land, using only the residual starches as feedstock for fuel production. In fact, protein products for use in livestock, aquaculture, and pet food markets are expected to be the largest product created by weight of our Net-Zero 1 plant, currently under construction. We separate out the various components of every bushel of field corn that enters our process (including protein, oil, fiber, and starch). It is our goal to use the nutritional value present in every bushel to improve the food chain. That means that we prioritize improving the global supply of protein. Starches, on the other hand, are neither a significant source of nutritional value nor in short supply across the world. That’s why we use the residual starches, which are left over from producing high-value nutrition products, as feedstock for our fuels. Our goal is to use the whole kernel wisely to replace the whole gallon of fossil fuel responsibly.

Q. Does growing corn pollute the environment?

A. Quite the opposite. Aside from farming—going back some 12,000 years—large-scale carbon capture does not exist. Gevo embraces sustainable agriculture and partners with farmers to improve their farming practices. Our partner farmers capture carbon in the soil with sustainable practices such as precision agriculture and conservation tillage. They optimize the chemicals applied to the land for the benefit of the soil by using low-tillage and no-tillage practices, by managing groundwater run-off with drain tiles, and by using manure rather than synthetic nitrogen. Additionally, there are several technologies, such as those offered by Locus Ag Solutions, being developed that could increase this carbon capture by an order of magnitude or more by enhancing soil quality and root-system growth.

Q. What does Gevo do with the protein produced from feedstock and why is protein so important for the food system?

A. Gevo’s process ensures that the protein produced from our feedstocks remains in the food system, through animal feed, pet nutrition, and aquaculture, helping to improve the availability of this crucial protein for the world while simultaneously working to mitigate climate change by producing low-carbon, drop-in fuels.

Q. Does SAF from corn increase food prices?

A. No. Gevo uses inedible field corn to create high-value nutrition products, such as high-protein animal feed from the same corn that we use to make our fuels, so food price increases are not a result of using corn to make SAF. Our focus is on paying farmers fairly for the value they create through regenerative farming practices, on ensuring that we reduce or eliminate waste in every part of our value chain, and on improving access to sustainable hydrocarbons, fuels, and other products.

Q. Is nonfood starch the best feedstock for sustainable aviation fuel?

A. It’s the right place to start. Over the long run, many sources of renewable carbohydrates could be used. Gevo’s technology enables the use of sugar, molasses, and lignocellulosic sources from agricultural residues like straw and stover, sugars from wood, and from municipal solid waste. In choosing feedstocks, the key criteria are sustainability profile, price, volume and—importantly for Gevo—giving local farmers additional revenue streams for their products.

Q. Why does Gevo use corn as a feedstock instead of municipal solid waste which could help solve the waste problem?

A. We use corn because it is sustainable, renewable, biogenic and has the natural ability to capture carbon. The best thing to do with municipal solid waste is to reduce or eliminate it, by diverting garbage from landfills and reusing and recycling more efficiently. The second-best usage is to capture landfill methane for local direct energy production. If municipal solid waste can be separated from fossil-based products such as plastic bottles, then there is potential for its use as a feedstock. But since GHG emissions are caused by the burning of petroleum/fossil-based products, burning plastics made from fossil carbon also contributes to the GHG footprint. These feedstocks need to be tracked and proven to be sustainable and renewable.

Q. How does Gevo guarantee that its product is sustainable?

A. To verify sustainability claims for bio-based products globally, Gevo has relied on the expertise of trusted third-party groups. In the past, Gevo has been certified by two such independent watchdogs, the Roundtable on Sustainable Biomaterials (RSB) and the International Sustainability and Carbon Certification System (ISCC). In achieving certification from these organizations, Gevo ensured that the sustainability of its feedstocks was confirmed by third-party review, and the resulting carbon emitted using its fuels could be considered a renewable resource. Gevo currently holds Roundtable of Sustainable Biomaterials (RSB) certification, and hopes to explore certification for our future facilities and partners.

Q. How do the Roundtable on Sustainable Biomaterials (RSB) and the International Sustainability and Carbon Certification System (ISCC) view corn?

A. Sustainably grown materials are not viewed differently from any other feedstock. Sustainability certifications issued by bodies such as the RSB and ISCC ensure that third-party standards are met.

Q. Will corn feedstock-based fuels be eliminated from certification under RSB and ISCC?

A. No, corn is not set to be eliminated. Sustainability certifications only set standards for products to meet. Creating such standards enable more qualified claims to sustainable feedstocks, including corn.