A. The Land Grant University System, Resource Limitation, and the Impending Biological Revolution

The United Nations predicts that by 2050 agricultural production will need to increase by 70% to feed a population of 10 billion. However, in the upcoming decade, agriculture and forest systems are going to be plagued with opposing and intersecting demands: climatic threats, population growth and migration, increasing food and energy pressures, decreasing water and land availabilities, soil degradation, supply chain disruption, and rising energy, labor, and chemical costs as well as degrading natural habitats and ecosystem services. The breadth of these intersecting problems is so vast that constructive solutions can only be developed and implemented through collaborations that cross traditional disciplinary boundaries. Replacing existing petroleum-based energy and products with those that are stemming from biomass will require research and development with a broad scope.

Specifically, the objectives of this project are to address research that are aligned with current administration priorities, such as but not limited to, climate change, artificial intelligence, resilient infrastructure, carbon-smart agriculture, and sustainable aviation fuels. From a human capital perspective, renewable energy and by-product production systems usually intersect with those of biomass production such that the ensuing processing facilities are typically located in agrarian areas, promoting rural economic development. To transition from fossil-fuel-based-systems to economically-viable- biomass-based systems fundamental and applied research is urgently required. Without these substantial research efforts, the technical capacity to switch from a fossil fuel-based economy to a diversified bioresource-based economy will be severely limited by unanswered questions, undeveloped technologies, suboptimal bioresource production and utilization, and missed opportunities to thwart climate change.

Multistate linkages are needed to address the breadth of the needed research. The research framework proposed herein is designed to address these limitations with the expertise of professional scientists and engineers primarily associated with the Land Grant University (LGU) system, which partners with important policy-setting agencies such as the United States Departments of Agriculture (USDA), Energy (US DOE) and Defense (US DOD), as well as the National Science Foundation (NSF) and various state agencies to meet its research mission. Additionally, the recent unprecedented National Resources Conservations Service’s Partnerships for Climate-Smart Commodities investments will require development of knowledge and ensuing practices for the successful implementation of its findings. Thus, there will be a pressing need for the science and engineering that will be developed in this Multistate project, such that society can seamlessly transition to consuming sustainable and biobased commodities and enjoying renewable energy sources. 

B. How S-1075 enabled new renewable energy industries.

Increasing the breadth of economically viable renewable energy and by-product production implies the generation of power and second-generation liquid biofuels, as well as bioderived chemicals that can be petroleum additions or even replacements. Such efforts lead to a more circular and carbon neutral bioeconomy. Researchers in the S-1075 Multistate project are advancing this goal through research into most facets of production systems for bioenergy and associated co-products, as detailed below.

B.1. Feedstock

Efficient feedstock supply chains are needed at commercial scale to enable the successful deployment of biobased systems. Progress was made in securing an abundant, economical supply of biomass feedstock delivered with predictable specifications that meet conversion needs. Biological feedstocks from areas representative of the various LGU partners were evaluated for biomass yield, composition, and other characteristics. S-1075 researchers at MN, MA, MT, ND, , NY, OH, PA, KY, TN, WA, and WI have tested a range of biomass feedstocks included switchgrass, wood chips and residues, giant miscanthus, energy cane, camelina,  and sweet sorghum with an emphasis on improving feedstock yield and convertibility to fuels and products, lowing the fertilizer and energy input and better understanding logistics requirements [1-6].

Sustainable supply of a biobased feedstock requires efforts to not only improve the yield and convertibility of a biomass crop but also reduce the production costs. The boundary of feedstock logistics is being extended to incorporate fertilizer and energy costs as well as operations like harvesting, baling, infield aggregation, storage, hauling, value addition (densification), and so on. The year-round supply of commercial quantities of uniform-consistency biomass depends on the specific commercial deployment of biorefineries. Hence, the integration of supply and conversion should be as seamless as possible. Such a complex system demands a systematic understanding of feedstock type and characteristics, availability and costs, pre-conversion processes, and logistics systems.

Although, great strides were made in terms of predicting biomass crop yields and quality on selected areas, knowledge gaps still remain in: 1) expected yields of these energy crops throughout US available land; 2) spatial and temporal variations in yield and supply due to climate and soil conditions including development of new sensors and algorithms; 3) harvesting and handling of these low bulk density materials;  4) developing new tools and models that identify target physical properties important at the interface of processing and conversion; and 5) evaluating the sustainability and climate-smartness of the biomass feedstock production and transportation system.

B.2 Conversion

In the past years, S-1075 participants worked on researching and developing technically feasible, economically viable and environmentally sustainable technologies to convert biomass resources into chemicals, energy, and materials, setting-up the foundations for future biorefineries. Developing co-products from biomass feedstocks became a focus area because biomass derived non-fuel co-products can meet the needs of renewable chemicals and materials traditionally made out of petroleum. Such efforts include valuable products from lipids and residuals from lipid processing, lignin and other cellulosic components.

Thermochemical conversion (TCC) technologies, such as co-firing/co-combustion, direct combustion, gasification, pyrolysis, torrefaction, and hydrothermal liquefaction (HTL), play critical roles to convert various biomass feedstocks to bioenergy, biofuels, biomaterials, and/or bio-products. These technologies have been proven technically feasible, however, there are significant needs for solutions to effectively tackle the challenges (such as low conversion efficiency, cost intensive, greenhouse gas (GHG) emission, and potential environmental impacts) to improve conversion efficiency and processing costs, while reducing carbon footprint in the circular bioeconomy. Advanced data analytic tools, including machine learning/artificial intelligence, internet of things (IoT), big data, high performance computing, cloud communication and storage, as well as new technologies (e.g., plasma-assisted pyrolysis, and hydrogenation bio-oil upgrading) need to be integrated to overcome the existing challenges, and thus move forward the TCC platform. Such advances can only be achieved through a Multistate approach.  

As opposed to thermochemical processing, biochemical conversion typically takes place at milder temperatures in an aqueous environment. This processing platform is based on the saccharification of the plant cell wall structural carbohydrates to produce high quality sugar streams that can be converted to biobased fuels, chemicals and products.  System/synthetic biology approaches are being developed by S-1075 participants to improve the yield of high value products from biomass components. For example, Clostridium strains were engineered for fatty acid ester production from corn stover hydrolysates [7] with a butyl acetate yield of up to 32 g/L being achieved, which is the highest ever been reported from microbial production [7-9].  Bioengineered oleaginous yeast Yarrowia lipolytica facilitated conversion of lipid-based feedstock to terpene-based specialty chemicals [10, 11]. These studies help to understand the dynamic of the membrane and storage lipids and the role of lipid metabolism in development and stress response.

Lignin is the second largest renewable polymer after cellulose and is the largest source of aromatic compounds. Economically feasible biorefinery scenarios must use all the components (including lignin) from the biomass to produce a diverse mix of fuels, materials, and chemicals according to their highest value [12].  However, due to lignin’s amorphous structure and cross-linked nature, its valorization is challenging and requires additional research. S-1075 participants are actively involved in lignin valorization research using a variety of technologies.  Lignin products have been converted to many products including adhesives, antioxidants and antimicrobials, 3D-printing materials, hydrogels, and resins [13-17]. Additionally, lignin derivatives have been used as a feedstock to produce liquid fuels/lipids, chemicals, and energy materials such as graphite, nanocomposite, and carbon dots [18, 19]. Challenges that exist for lignin utilization include both separation and purification from biorefinery streams. The chemistry of these streams significantly impacts isolation processes. After extraction and purification, lignin may also require additional modification to achieve the desired properties in material application.

Although great strides were made in co-product research, knowledge gaps remain related to integration of these technologies to produce second-generation production systems that are coupled to economically viable energy systems. Knowledge gaps also remain in understanding the environmental impacts of these systems, including carbon footprint. Sustainability metrics such as socioeconomic and environmental indices are needed to assess biorefinery systems [20]. Effective metrics can help to identify and quantify the sustainability attributes of biorefinery processes and products. However, methodologies and outputs need to be adapted to produce reliable and publicly understandable results. Additionally, tradeoffs between different socioeconomic and environmental indicators need to be considered. Conventional indicators describe both environmental impacts, such as GHGs, eutrophication, net energy, and fossil fuel usage, as well as socioeconomic impacts, such as social well-being, energy security, trade, profitability, and acceptability [21, 22]. This suite of indicators will need to apply to the full biorefinery supply chain including feedstock production and logistics; conversion to fuels, chemicals and materials; and end uses.

B.3 System analysis and logistics

The supply chain and conversion platforms for bio-based products exist in interconnected systems. Spatial and temporal variability is inherent in these systems and needs to be accounted for in any modeling effort [23].  For instance, spatial variability injects bias into LCA calculations when applied to the local conditions or decision-making parameters [24]. Integrated modeling frameworks characterizing variability and reducing uncertainty would provide better information to decision-makers and policy planning. Modeling frameworks also need to be sufficiently robust to account for emerging types of system attributes such as circularity and decentralization. 

Modeling frameworks that capture spatial and temporal variability are especially important for decentralized biomass processing systems that employ small-scale depots to upgrade biomass to saleable commodities, e.g., pellets, briquettes, bio-oil, and biogas.  Regionally distributed depots are predicted to reduce biomass transportation costs while providing income for farmers and forest landowners.  Depots will also increase the tax base in rural communities, leading to resources that can be used to improve rural infrastructure, education, and health care.  As investment in depots is much lower than in full scale refineries, overcoming the “chicken and egg” dilemma that has stymied bioenergy and bioproduct commercialization might be expedited by decentralization.    

C. Research needs/justification for the next 5 years

Utilization of biobased resources for production of renewable energy and materials is key to enable circular bioeconomy. Biobased resources are highly variable and non-homogeneous, and climate and geographic dependent. R&D efforts are needed to develop robust technologies for low-cost and efficient harvest of different bioresources and to handle their non-homogeneity, and to achieve zero or near-zero emission conversion. Furthermore, there is a need for increased attention on bioprocesses optimized for carbon removal, or permanent removal of carbon dioxide from the atmosphere. Specifically, biofuels, biochemicals, and biomaterials that have net negative carbon footprints over their entire lifecycle. Examples include ethanol fermentation with geological storage of CO₂ produced in the bioreactors, and pyrolysis with geological storage of bio-oil and soil storage of biochar.

For the biological conversation technologies, the microbial strains are the key players. Special attention should be paid to develop robust strains though the innovative metabolic engineering and synthetic biology strategies. The metabolic engineering and synthetic biology work will take advantage of the burgeoning machine learning (ML) artificial intelligence (AI), big data, new materials and novel sensors, and bioinformatics technologies. On one hand, it is necessary to develop workhorse technology that can handle low-value recalcitrant waste streams (including the emerging organic waste of environmental concerns, such as municipal solid waste and plastics), with an aim to produce high-value biochemical and bioproducts, besides biofuels.  In addition, integrating the biological process with other processes, including the chemical catalytic, electrocatalytic, and photocatalytic (artificial photosynthetic) processes can greatly improve the conversion efficiency and economic feasibility.

In addition to the improvement of biofuel technology itself, product diversification is an important aspect for promoting circular economy principles. Therefore, co-product development should remain a focus of the S-1075 research community. Given the diversity of biomass feedstock and multiple fractions of biomass, researchers of complementary expertise (e.g., biological, thermochemical, and electrocatalytic) will collaborate with each other to develop multiple streams of products and co-products from biomass. Conversion of biobased resources into value added products could be, but are not limited to, food and food additives, fiber, packaging, pharmaceutical and biomedical products. However, there are several interrelated gaps for the production of these commodities to become economically feasible and these include: scaling-up to an industrially relevant production system; achieving economically competitiveness; reconfiguring bioprocessing technologies to maximize negative carbon emissions and maximizing greenhouse gas benefits; identifying the correct funding landscape for transitioning to beta scale production; and, managing the business and corporate culture related issues that are associated with new technology adoption and commercialization.

There will be a need to address the shift from a carbon-emitting petroleum-based economy to a carbon-negative bio-based economy that does not disrupt the existing global food supply chain.  Mapping bioproducts to their fossil counterpart and identifying materials transition pathways will be critical. In short, it will be critical to determine pathways for economically viable biobased commodities and renewable energy production within existing or realistic production constraints. The breadth of the problem is shocking and will require an interdisciplinary approach that will draw from engineering, biology, biochemistry, chemistry, material science, soil science, agronomy, and agricultural economy.

D. Funding landscape: Challenges and Opportunities for the next five years

Biomass-derived renewable energy and bio-products is finding renewed interest, especially because of the urgent need to mitigate climate change, minimizing greenhouse gas emissions and increasing atmospheric carbon capture. However, there is a sweet spot where climate mitigation practices and techniques need to intersect with economic feasibility, finding this coveted space, where these compromises can occur, requires research efforts.  Additionally, there is interest in fitting all aspects of biomass-derived, manufacturing, distributing, and discarding of energy and bio-products within the confines of the circular economy. A variety of program funding continue to be available through AFRI FAS (USDA NIFA), Sustainable Agricultural Systems (USDA), Sun Grant Initiative (USDA), NSF, as well other targeted initiatives, such as the Sustainable Aviation Fuel initiative and the Bipartisan Infrastructure Law. Participants of the Science and Economy Multi-State project see this funding landscape as an important mechanism for maintaining connection, continuity, and versatility in meeting research demands in a dynamic funding environment.