Hexas: A sustainable solution to the food vs. fuel debate
By planting its proprietary grass on unproductive land, Hexas wants to provide a viable alternative to traditional food crop-based biofuels.
In the ongoing debate over agricultural land use for fuel crops, Hexas stands out for pioneering a sustainable approach that sidesteps the controversy.
By developing a proprietary grass called XanoGrass, which thrives on non-productive farmland and from which it produces the XanoFiber feedstock, Hexas aims to provide a viable alternative to traditional food crop-based biofuels.
Focus on marginal and abandoned crop land
The "food vs. fuel" debate has long been contentious, with critics arguing that using farmland to grow fuel crops is unethical.
Jean Ziegler, the former UN special rapporteur on the "Right to Food," even went so far as to call the practice a "crime against humanity" back in 2007.
Hexas acknowledges the problematic nature of fuel crop use, pointing out that humans cut down 15 billion trees each year and dedicate 80 million acres of cropland to produce biofuel from food crops.
However, Hexas' approach is different. According to Wendy Owens, the company's founder and CEO, there are up to 83 million hectares of marginal and abandoned crop land worldwide – farmland that has been left idle due to over-fertilisation, high salination, and a lack of topsoil and nutrients.
This is where XanoGrass comes in. "What we do is grow on that land," Owens explained, giving farmers an opportunity to generate income they would otherwise not have had from otherwise unproductive land.
XanoGrass can regenerate farmland
Not only does XanoGrass provide a new revenue stream for farmers, but it also has regenerative properties. The grass can be used for bioremediation, removing chemicals and heavy metals from the soil. As a nitrogen fixer, it adds nutrients to depleted soil, allowing it to be used for food production or to return to its native state.
"XanoGrass is much more land-use efficient. We can produce five times more ethanol per hectare than corn."
The grass boasts an impressive yield of 50-80 dry tonnes per hectare, also surpassing sugarcane, which is increasingly used as a feedstock in the alcohol-to-jet pathway. "Sugarcane is very hard on the soil. It requires a significant amount of pesticides; we actually don't use pesticides ever," Owens added.
We won’t need Wyoming
Other fuel crops like Miscanthus can also grow on marginal farmland. In a 2022 study, researchers from Arizona State University found that planting Miscanthus on marginal agricultural lands across the United States would provide enough biomass feedstock to fully meet the liquid fuel demands of the U.S. aviation sector from biofuels.
However, critics have pointed out that the vast amount of land the study estimates would be needed — 23 million hectares — is equivalent to the US State of Wyoming.
Owens argues that XanoGrass provides a better solution:
“Miscanthus is going to be maybe 20 to 24 dry tonnes per hectare, whereas we're going to be 50 to 80 dry tonnes per hectare, depending on where we're growing. And so that's a significant difference because it's much more land-use efficient. We're not going to have to use all of Wyoming."
XanoGrass is also versatile and capable of growing in a wide range of environments. Owens says they’ve been growing in Hungary for the past five years, where it gets quite chilly there. But they’re also growing in Hawaii, for example, and in Arkansas. “There's a very wide range of areas in which we can do production," she says.
Owens wouldn’t be drawn into the likely end cost of a biofuel that uses XanoGrass, as Hexas does not make the fuel; it provides the feedstock to energy companies that do. As a result, several variables are at play, such as the pathway and technology used by the SAF manufacturer.
However, that feedstock could, for example, be used in an alcohol-to-jet plant, such as the one LanzaJet has opened in Georgia.
The potential applications of XanoGrass extend beyond biofuels. The grass can be used in various industries, from building materials and textiles to prebiotics and biochemicals. "We really want to get the highest and best use out of the biomass we're producing," Owens emphasised, highlighting Hexas' commitment to sustainability and efficiency.
Our take
Hexas' solution appears to be quite transformative in addressing the "food vs. fuel" debate and offering a sustainable alternative to traditional biofuel crops. It doesn’t compete with food crops on arable land, has regenerative capabilities, has a high yield, and offers many possible use cases.
As a result, if the company can scale up its operations and find acceptance among SAF producers wanting to take its feedstock, it could potentially play a large role in helping aviation and other transport sectors wean themselves off fossil fuels.