In this blog post, we will examine the environmental and economic challenges of biofuels—which have long been touted as an eco-friendly energy source—and consider the direction the sustainable biofuel industry should take to move beyond its reliance on conventional first-generation biofuels.
As concerns about environmental pollution—which has been accelerating since the Industrial Revolution—have grown, humanity has developed the green energy industry, utilizing renewable energy sources as a means to replace fossil fuels. Biofuels have also established themselves as a key pillar of this renewable energy sector. The core idea behind biofuels is to utilize the energy that living organisms synthesize and store on their own. The types of biological resources that can be used as biofuels are quite diverse, ranging from first-generation biofuels—which utilize food crops such as corn and sugarcane—to second-generation biofuels—which use non-food agricultural waste, grasses, and trees—and third-generation biofuels—which utilize algae and other marine organisms. However, current biofuel production methods present various environmental and economic challenges. This is not to say that I oppose the biofuel industry itself. Rather, I believe the industry should not move in a direction that relies too heavily on traditional biofuel production methods.
When people hear the term “biofuel,” they often think of green energy and consider it environmentally friendly. However, it is worth questioning whether all biofuels are actually eco-friendly. Supporters of first-generation biofuels argue that since the carbon dioxide absorbed by plants during their growth is re-emitted during the use of biofuels, net carbon dioxide emissions are close to zero. However, this logic is problematic because it does not sufficiently account for the additional energy consumption and greenhouse gas emissions generated during the production, transportation, and processing of biofuels. In fact, when assessing the environmental impact of biofuels, a life-cycle assessment is necessary that takes into account all greenhouse gas emissions generated during feedstock production and transportation, fuel production and distribution, and fuel use.
In the case of corn or sugarcane, which are used as feedstocks for first-generation biofuels, the plants accumulate a significant amount of energy as they grow; however, the process of converting them into fuel requires additional energy for farming, harvesting, transportation, and processing. Consequently, producing sufficient quantities of biofuel to meet demand requires vast tracts of farmland. Since existing farmland is already used for food production, developing additional farmland may be necessary to grow crops for biofuel. This process carries the risk of damaging forests and natural ecosystems, as well as causing environmental pollution. But that’s not all. Extracting biofuel from plants also requires a significant amount of energy, and the energy used in this process often relies on fossil fuels. Therefore, we should not assume that biofuels are unconditionally better for the environment than fossil fuels. In fact, the U.S. Environmental Protection Agency (EPA) explains that when evaluating the environmental impact of biofuels, it comprehensively analyzes greenhouse gas emissions generated throughout the entire process—from feedstock production to fuel production, distribution, and use—and notes that results may vary depending on the feedstock and production method. Considering these factors, it is inappropriate to judge biofuels as environmentally superior to fossil fuels simply because they are biofuels.
In fact, the bigger problem with first-generation biofuels is that they use food as an energy source. As demand for bioethanol increases due to environmentally focused policies, demand for food resources—such as corn and sugarcane, which serve as feedstocks—may also be affected. In particular, since a significant amount of corn is used for bioethanol production, the issue of competition between food and fuel has been raised. In the United States, more than 40% of corn is currently used for ethanol production, and U.S. corn-based ethanol production has remained stagnant at a high level in recent years. Ultimately, using agricultural products that could be used as food for fuel production can affect food prices and agricultural markets; in some cases, this can create an economic structure in which consumers indirectly bear the costs associated with biofuel production.
Currently, alternatives to first-generation biofuels include second- and third-generation biofuels. However, the biofuel industry still relies heavily on biofuels made from traditional feedstocks such as corn. In the United States, ethanol produced from corn starch remains the most widely supplied renewable fuel; U.S. corn ethanol production reached approximately 16.2 billion gallons in 2024 and was estimated to reach about 16.4 billion gallons in 2025. This is because, in the case of second-generation biofuels, feedstocks are scattered across various locations, making transportation and collection costly, and even for third-generation biofuels, technical and economic challenges remain. However, the reality is more complex. It is intertwined with vested interests and political issues involving biofuel companies. In the United States, biofuels have, in fact, been closely tied to politics. In particular, there have been instances where presidential candidates, seeking to win over voters in Iowa—a major corn-producing region—have taken the agricultural sector’s interests into account and presented bioethanol policies in a positive light.
However, this does not mean that the current trend of continuing to rely on first-generation biofuels—which have the potential to negatively impact the environment and the economy—is without problems. That said, mandatory biofuel blending policies vary significantly by country and fuel type, and it is difficult to simply assume that all countries mandate a blend of 5–10% or more. In the United States, the Renewable Fuel Standard (RFS) sets annual supply targets for each type of renewable fuel, with a total renewable fuel target of 22.33 billion gallons established for 2025. Furthermore, the U.S. system applies life-cycle greenhouse gas reduction standards based on fuel type and production method. For example, conventional corn starch ethanol produced at newly constructed facilities must meet a life-cycle greenhouse gas reduction standard of at least 20% compared to 2005 petroleum-based levels, while higher reduction standards apply to cellulosic biofuels and advanced biofuels. Brazil is also continuing its policy to expand biofuel use; it implemented “E30”—a blend of 30% anhydrous ethanol in gasoline—in August 2025, and “E32” has been in effect on a temporary basis since August 2026. Therefore, when considering the issues at hand, rather than simply abolishing biofuel blending policies, policies should be improved to reduce dependence on feedstocks and production methods with low environmental performance and sustainability, while comprehensively considering life-cycle greenhouse gas emissions, land use, and competition with food production. From a political perspective, such solutions may be difficult to implement solely at the national level. Therefore, it is necessary to actively promote efforts at the international level to reduce the production of less sustainable biofuels, or for international environmental organizations to establish and enforce sustainability standards. Rather than unconditionally expanding farmland developed for the production of first-generation biofuels, it may be wiser to consider the characteristics and ecological value of the land and use it for the restoration of natural ecosystems or conversion to other uses. Furthermore, the resources freed up by reducing subsidies for first-generation biofuels should be invested in the development of next-generation biofuels—such as second- and third-generation biofuels or those utilizing waste and residues—in an effort to gradually increase the proportion of sustainable feedstocks. So, what criteria should new biofuels that replace first-generation biofuels meet? I have identified three main criteria.
First, human intervention that causes environmental pollution must be minimized throughout the entire biofuel production process. In the case of first-generation biofuels, the production process may require the development of additional farmland; chemical fertilizers and agricultural inputs are used to ensure plant growth; and the harvested raw materials are transported to factories, where fuel is extracted through separate processing steps. Looking at this process, it is clear that a significant portion of biofuel production has the potential to place a burden on the natural environment. Thus, if the production process deviates too far from the natural cycle, the problems mentioned earlier will arise. Of course, it is possible to develop and implement artificial measures to reduce environmental pollution. However, this merely reduces pollution that has already occurred; it is difficult to consider it a fundamental solution that eliminates the environmental burden arising from the raw material production stage. Second-generation biofuels, previously mentioned as an alternative to first-generation biofuels, also face challenges in feedstock procurement; efforts are underway to address this by artificially planting fast-growing trees or grasses. However, since such efforts may place a burden on ecosystems due to large-scale monoculture and changes in land use, caution is needed when pursuing this direction. Therefore, utilizing raw materials that are abundant, do not compete with existing food resources, and minimize the impact on land use during the production process could be a better alternative. Third-generation biofuels using seaweed are also among the candidates with such potential. Seaweed has growth characteristics different from those of terrestrial plants and offers the advantage of avoiding direct competition for land with food crops. Of course, the environmental impact of harvesting seaweed from the ocean or cultivating it on a large scale must be carefully considered, and the energy consumption and costs associated with production, harvesting, and extraction must also be addressed. Therefore, while acknowledging the potential of seaweed, we must also consider that challenges remain in terms of commercialization and economic viability.
Second, the requirement for “sustainability” must be met. One of the ultimate goals of the renewable energy industry, which is currently undergoing continuous development, is sustainability. In other words, we must pursue a path that secures a stable, long-term energy source while minimizing environmental damage. However, do first-generation biofuels—which fall under the category of renewable energy—sufficiently meet sustainability requirements? Considering that plants such as corn and sugarcane require continuous management, and that large-scale monoculture can reduce biodiversity and disrupt the balance of ecosystems, it is clear that there are various limitations. Even in the case of wood used as a second-generation biofuel, since it takes a considerable amount of time to grow, a stable feedstock supply system must be established to meet sustained, large-scale consumption. Therefore, if we become overly reliant on specific feedstocks for second-generation biofuels, consumption rates could outpace growth rates, potentially leading to resource depletion. In contrast, seaweed—which is being researched as a feedstock for third-generation biofuels—has the advantage that many species exhibit relatively fast growth rates and can be produced in ways that do not directly compete with existing terrestrial farmland. However, it cannot be concluded that seaweed is unconditionally sustainable. This is because the processes of large-scale cultivation, harvesting, drying, and fuel extraction require energy and resources. Ultimately, the most important thing is not to unconditionally choose a specific generation, but to develop production methods that can reduce resource and energy consumption and lower the environmental burden throughout the entire process.
Finally, biofuels must be sufficiently price-competitive compared to fossil fuels. Why have fossil fuels continued to account for a large share of total energy consumption for so long, even though they are identified as a major cause of environmental pollution? This is because fossil fuels are backed by a long-established infrastructure for production, transportation, and storage, and they offer advantages in terms of price and convenience. Therefore, no matter how environmentally friendly biofuels may be, it will be difficult for their consumption to increase dramatically if they are not price-competitive. Even if their use is mandated by policy, there will inevitably be certain limits to expanding consumption due to the cost burden on producers and consumers, as well as conflicting interests with the existing energy industry. Among current biofuels, first-generation biofuels—for which large-scale production systems are already in place—have a relative advantage in terms of price competitiveness; the ability to utilize existing infrastructure is also one of the reasons for their high production volumes. In contrast, second-generation biofuels often involve more complex production processes than first-generation biofuels. In the case of agricultural waste, resources are scattered across various locations, making it costly to collect them in one place; furthermore, the pretreatment and processing required to extract fuel from complex biomass structures are challenging. What about third-generation biofuels? While algae itself has the advantage of being highly renewable and not necessarily competing directly with terrestrial farmland, there are still issues: the process of extracting fuel from algae is currently costly, and it is difficult to reliably establish large-scale production, harvesting, and processing systems. Therefore, it is difficult to consider this technology fully commercialized at this point. However, if technology advances to enable mass production and efficient harvesting and extraction, and if the energy and costs required throughout the entire process are reduced, it has the potential to become sufficiently price-competitive.
In summary, first-generation biofuels can impose environmental burdens due to land use, agricultural activities, and energy consumption during the production process, and they have the potential to cause economic and social problems because they use food crops as feedstock. Nevertheless, since large-scale production systems and infrastructure are already in place, the biofuel industry still relies heavily on first-generation biofuels. Therefore, more resources should be invested in the development of third-generation biofuels or next-generation biofuels—particularly technologies that utilize feedstocks that do not compete directly with food, such as waste and agricultural residues—to ensure sufficient price competitiveness and environmental performance, and to move toward a future that pursues both environmental friendliness and sustainability. Of course, developing next-generation biofuels capable of completely replacing fossil fuels will require considerable time and technological advancement. Even so, it is not advisable to unconditionally expand the large-scale production of first-generation biofuels using specific feedstocks without fully considering the environmental and economic issues involved. The future of the biofuel industry lies not simply in increasing biofuel production, but in carefully considering which feedstocks to use, how to produce them, and how to minimize the environmental impact throughout the entire production and consumption cycle. Therefore, active international efforts are needed to reasonably reduce dependence on first-generation biofuels and to develop highly sustainable next-generation biofuels.
