Burning biomass to generate electricity is certainly one option and is already practiced in many places, including in cellulosic biorefineries, where leftover lignin is combusted to power the facility. This is what we, at GranBio, do in our own processes. However, liquid fuels derived from biomass offer advantages that electricity from burning cannot: they are energy-dense, storable, transportable, and compatible with existing engines and infrastructure (meaning they are “drop-in” fuels). This makes them particularly valuable for sectors like aviation, maritime shipping, and heavy transport, where direct electrification remains impractical in the near term.

A wide variety of plant-derived materials qualify as cellulosic biomass. These include agricultural residues such as sugarcane straw and bagasse, corn stover (stalks, leaves, and husks), and wheat straw; forestry residues such as wood chips and sawdust; dedicated energy crops like eucalyptus, switchgrass, and miscanthus; and even wood from construction debris. At GranBio, we have successfully demonstrated the use of over 20 types of feedstocks to produce second-generation ethanol and other platform chemicals with industry-leading yields.

Cellulosic biomass refers to non-food, lignocellulosic plant materials such as forest and agricultural residues, industrial wood waste, and dedicated energy crops. These materials have three main components: cellulose and hemicellulose (which are suitable for conversion into low‑carbon fuels and biochemicals) and lignin, a rigid polymer that binds them together and gives plants their structural strength. Unlike the starch or sugar found in grains and fruit, cellulosic material is largely indigestible, which is why it has historically been discarded or burned, but with the new advancements in biotechnology we can now harness cellulosic biomass' full potential. Learn more here.

Yes, essentially we take what is left behind from the plant after its primary use, aka “waste”, which is also classified as cellulosic biomass as it is derived from a plant. For example, when sugarcane is crushed for sugar, the fibrous straw and bagasse remain. When wood is cut for logging, there are usually residues left behind, which tend not to be collected as they have no further use, being left in the field to naturally decompose. The same happens with agricultural residues, such as corn stover. Turning this kind of residue into added-value biofuels and biochemicals doesn't just reduce emissions - it solves a waste management problem, and it can also help with fire prevention. Learn more about circular economy here.

The difference lies in the feedstock source and the carbon intensity. Corn ethanol (1G) uses the starch from food crops, whereas cellulosic ethanol (2G) uses the "woody" parts of plants (lignocellulose). Because 2G feedstocks are often waste products, cellulosic ethanol has a significantly lower carbon footprint and avoids the "food vs. fuel" ethical dilemma.

Lignin functions like a glue in the plant cell wall, holding all components together. Breaking it down is one of the central challenges of 2G ethanol production. Once separated, lignin becomes a valuable co-product. In most biorefineries, it is combusted to generate the heat and power needed to run the plant, making the process largely energy self-sufficient. GranBio’s AVAP® technology takes this recovery one step further – the process produces native lignin and lignosulfonates, which can be used in materials such as tires and plastics, or converted into biofuel. Learn more in our Technologies page.

Cellulosic ethanol, also called second-generation (2G) ethanol, is ethanol produced from the fibrous, non-edible parts of plants rather than from their sugars or starches. The "generations" refer to the evolution of biofuel technology: first-generation (1G) ethanol uses food crops like sugarcane juice or corn starch; second-generation (2G) ethanol uses agricultural residues and woody biomass. The 2G designation signals a fundamental leap in sustainability and feedstock efficiency.

Second-generation ethanol has three main production pathways: 1. biochemical pathway, 2. thermochemical pathway, and 3. hybrid pathway, with the latter being a combination of the former two.

GranBio has two patented processes to produce second-generation ethanol: GreenPower+, a robust and simple process, and AVAP, a best-in-class technology for conversion of biomass into biochemicals, advanced materials, and biofuels. GP+ uses the thermochemical pathway, meaning it relies on water steam and mechanical compression to separate the cellulose and hemicellulose carbon chains that are then cut by enzymes into C5 and C6 sugars.

AVAP maximizes yield through a chemical fractionation process to extract the saccharides. On both GP+ and AVAP, the sugars are then fermented, and the resulting mixture is distilled and purified into fuel-grade ethanol, which can be further processed for different end-uses such as biochemicals, advanced materials, and sustainable aviation fuel. The lignin separated during pre-treatment is not wasted: it is typically burned to generate heat and electricity for the plant itself, dramatically reducing the facility's energy footprint. GranBio’s AVAP technology takes this recovery one step further – the process produces native lignin and lignosulfonates, which can be used in materials such as tires and plastics, or converted into biofuels. At specific phases of both processes, AVAP and GP+, we can also extract nanocellulose. Learn more about GranBio’s technology here.

AVAP® is feedstock flexible. GranBio successfully converted over 20 biomass types of forest and agricultural biomass into fuels, chemicals, and advanced materials. These residues do not compete with food nor land for food production. Learn more here

AVAP® is GranBio's biomass fractionation technology that converts different types of biomass into high-purity cellulosic sugars, lignin and other renewable products.

AVAP® is the gold standard for transforming cellulosic biomass into sustainable products with the lowest carbon footprint and at a competitive cost, compared to carbon capture alternatives. It delivers industry-leading sugar yield rates and offers significant CAPEX advantages compared to greenfield projects. Learn more here

Yes. In the United States alone, the "Billion-Ton Report" from the Department of Energy identifies over one billion tons of available biomass that can be harvested annually without harming food production. Globally, wood waste and agricultural residues provide a massive, underutilized energy reservoir capable of displacing a significant portion of fossil fuel use. Most of this biomass is currently burned, left to decompose, or landfilled — representing a large unused resource. With GranBio’s technology, production of 1 billion GPY of SAF uses about 13 MM dry TPY of residual biomass.

Yes, when managed sustainably. Our process only utilizes "excess" residues. Leading agronomic studies show that leaving a percentage of residue on the field helps sequester Soil Organic Carbon (SOC) and prevents erosion, while the surplus can be safely harvested for high-value biochemicals. Responsible removal of residues:

• Reduces wildfire risks
• Improves forest health
• Avoids methane emissions from decomposition
• Uses only a portion of residues, leaving the rest to maintain soil nutrients.

At GranBio, all biomass used in our processes is sustainable sourced - either directly by us or through experienced partners in responsible biomass harvesting and handling. Learn more in our SAF page, under "Feedstock".

Harvesting cellulosic biomass reduces "ladder fuels"—the dead wood, overgrown brush, and forest floor debris that allow small ground fires to climb into the tree canopy and become catastrophic crown fires. By removing this excess wood waste, we create safer forest structures that mimic natural, healthy ecosystems, significantly lowering the risk and intensity of mega-fires.

In many regions, forests are overcrowded due to decades of fire suppression, which chokes out sunlight and prevents young, diverse plant life from growing.

Thinning these areas for cellulosic feedstock:

• Increases Biodiversity: Opens the canopy to allow sunlight to reach the forest floor.
• Improves Water Availability: Reduces the number of "thirsty" small trees, leaving more water for the remaining old-growth timber and local watersheds.
• Restores Habitats: Creates a mosaic of different forest ages and types, which is essential for various wildlife species.

HEFA stands for Hydroprocessed Esters and Fatty Acids. It is the most mature SAF technology today, using feedstocks such as used cooking oil (UCO) and animal fats. However, the industry is moving toward lignocellulosic pathways, mainly due to HEFA’s forecasted feedstock scarcity. There isn't enough waste oil in the world to supply the forecasted demand, leading to high prices and potential supply shortages.

SAF is a type of jet fuel that is produced using alternative, low-carbon feedstocks to crude oil. Qualifying feedstocks are varied, ranging from cooking oil (HEFA), forest residues, municipal waste, waste gases, and agricultural residues – to name a few. GranBio's Ethanol-to-Jet technology offers significant advantages compared to other production pathways, such as lower cost and carbon footprint. Find out more here.

GranBio’s Cellulosic SAF can help hard-to-abate sectors reach their net zero targets as it has the potential to reduce carbon emissions by up to 98%. On the one hand, biomass residues incur zero emissions during production per international LCA (Lifecycle Analysis) methodology. On the other hand, the carbon released during flight belongs to a "closed-loop" cycle - we’re not adding "new" carbon to the atmosphere, just using the one from the natural cycle, as opposed to what happens with fossil sources. Check out our "Production Pathways Comparison Table" here.

Unlike HEFA, which relies on limited waste fats and oils, cellulosic SAF uses abundant agricultural and forest residues. While waste oils are measured in millions of tons, cellulosic biomass is measured in billions of tons. By utilizing wood waste and corn stover, for instance, we provide a feedstock supply that is vast, geographically diverse, and entirely decoupled from the food and oil markets.

There are five main technology pathways to produce Sustainable Aviation Fuels:

• Alcohol‑to‑Jet (ATJ)
• Gasification Fischer‑Tropsch (FT)
• Hydrothermal Liquefaction
• Power-to-Liquid (e-SAF)
• HEFA

While the first three pathways use lignocellulosic biomass (LCB) as a feedstock, PTL uses captured CO2 – via Direct Air Capture (DAC) for instance – and HEFA uses oils and fats. Compared to other pathways, GranBio’s technology offers significant advantages in carbon footprint, yield and cost. Check out our SAF product page to learn more.