Effects of Liquid Biofuels on Carbon Emissions

Biofuels from corn, soy, palm oil, organic waste, grasses, perennial cellulose crops, algae, and more, have been researched, designed, and tested as viable alternatives to fossil fuels. Technological and upscaling challenges have repeatedly hampered their widespread use.

FREMONT, CA: As climate change has worsened over the past several decades, the need for efficient liquid biofuels, mainly to power the transportation sector, has intensified, exerting significant strain on fragile ecosystems and even resulting in bans.

Three generations of biofuels have been investigated, including corn, soy, palm oil, grasses, algae, and numerous other organic sources, with the majority falling short of their potential. Policymakers see biofuels as a green, carbon-reducing alternative to fossil fuels to wean the world off fossil fuels.

According to the IEA, global investment in liquid biofuels hovered at $4 billion over the past decade, tripling in 2021 to more than $8 billion. More is required to harness the potential of "advanced biofuels." In certain instances, government policies have backed or subsidized the business to billions of dollars. For example, the U.S. government's Sustainable Aviation Fuel Grand Challenge recently invested approximately $4.3 billion to promote research and assist fuel manufacturers in developing clean biofuels.

Despite these efforts, three obstacles have prevented some biofuels from entering the mainstream and others from escaping controversy: complex technological issues, the inability to accomplish cost-effective upscaling, and environmental damage (from deforestation to pollution).

According to a study published in Biological Conservation in March, the production and expansion of ethanol corn and soy crops in the United States are associated with various "negative environmental outcomes." These include "degraded water quality, increased water use, increased greenhouse gas emissions, and loss or degradation of wildlife habitat," which can impact endangered species.

Three generations of biofuel expansion and depletion

Liquid biofuels aren't new. In the 1970s, automobiles began to run on a blend of bio-based ethanol, with numerous experimental organic fuels rising and falling in popularity over the decades. Yet, as the need to decarbonize grows increasingly urgent, biofuels have increased, with nations, corporations, and researchers supporting numerous sources.

Three generations of biofuels have evolved, each with advantages and limitations and boom-and-bust cycles.

First Generation biofuels are bioethanol and biodiesel derived from corn, soy, oil palm, other crops, virgin vegetable oil, and animal fats. Third Generation biofuels (initially studied in the 1970s and '80s) are generated from algae.

None of these generations has generated a big bioenergy breakthrough that is good for the environment. Instead, the most recent report from the U.N. The Intergovernmental Panel on Climate Change (IPCC) suggests that liquid biofuels be primarily "focused on difficult-to-electrify sectors." It warns that they all suffer "significant challenges associated with their lifecycle carbon emissions."

The difficult-to-electrify sectors include shipping, aviation, and "heavy-duty land transport" (such as trucks), with the world predominantly benefiting from organic liquid fuels as a fossil fuel transition in the "near and medium term." Up to one-fourth of the world's greenhouse gas emissions are attributable to the transportation industry, which continues to be dependent on fossil fuels.

According to the IEA, the estimated global demand for liquid biofuels in 2021 was 159.2 billion liters (42 billion gallons); the majority are derived from food crops such as corn and sugarcane, while waste materials such as used cooking oil were the primary non-food feedstocks.

According to some experts, production and use must expand and diversify substantially to realize their much-touted sustainable energy production potential. In the same year, biofuels (mainly those of the first generation) supplied only 3.6 percent of global transport energy consumption; this must increase to 15 percent to satisfy climate objectives. Biofuel utilization in aviation, currently at 0.1 percent, is predicted to reach just 5 percent by 2030.

For instance, Brazil and the United States set ambitious plans for the global spread of biofuels. Together, these nations are already among the most significant consumers of biofuels and account for the most growth in the transportation sector. Scientists stress, however, that biofuels' sustainability dramatically depends on the feedstock used and that any expansion should be at a different price than biodiversity and climate objectives.