Biochemical Conversion Techno-Economic Analysis

NREL's biochemical conversion analysis team focuses on techno-economic analysis (TEA) for the biochemical conversion of biomass to fuels and products via sugars and other components derived from lignocellulosic biomass.

We help enable the production of cost-competitive hydrocarbon fuels and products from biomass in support of the U.S. Department of Energy's Bioenergy Technologies Office. The processes investigated through biochemical conversion analysis are broadly based on chemical, mechanical, and/or enzymatic deconstruction of lignocellulosic biomass to simple carbohydrates and other intermediates, followed by upgrading of these intermediate components to fuels or coproducts. TEA modeling helps to understand technical and economic implications for data gathered at bench- and pilot-scale operations, when extrapolated to a hypothetical commercial-scale integrated biorefinery.

Featured Publications

Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Catalytic Conversion of Sugars to Hydrocarbons, NREL Technical Report (2015)

NREL 2012 Achievement of Ethanol Cost Targets: Biochemical Ethanol Fermentation via Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover, NREL Technical Report (2014)

Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons: Dilute-Acid and Enzymatic Deconstruction of Biomass to Sugars and Biological Conversion of Sugars to Hydrocarbons, NREL Technical Report (2013)

Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover, NREL Technical Report (2011)

View all NREL biochemical conversion analysis publications.

Capabilities

Techno-economic analyses are performed to determine the potential economic viability of process technologies in the research and development stage. Evaluating the production costs of a given process technology, based on current performance and targets established for process improvements though research efforts, allows the analysis team to assess the potential economic feasibility of a process configuration. Results of these analyses are useful in determining which emerging technologies have the highest potential for near-, mid-, and long-term deployment success.

Conceptual process designs and detailed process models developed for TEA under this project allow the analysis team to evaluate aspects of process technology development like production costs, product qualities, heat integration, process optimization, and scale-up. The analysis team also assists the research efforts by helping establish technical targets for the research programs and quantifying the economic impact from research achievements. This helps direct research in the most impactful directions, with a goal of maturing toward commercial deployment. Sustainability metrics associated with the conversion processes are also tracked.

Within the Biochemical Conversion Analysis project, there are currently two primary integrated conversion pathways considered through TEA modeling, namely biological and catalytic conversion of sugars/hydrolysate.

Bar graph illustrating the R&D impact on the minimum ethanol selling price in 2007$ (y-axis) of corn stover to ethanol via biochemical conversion, from 2001 to 2012 (x-axis). The left half of the chart shows Conversion data in orange and Feedstock data in grey: 2001: Feedstock = $1.25 and Conversion = $7.91; 2002: Feedstock = $1.25 and Conversion = $5.65; 2003: Feedstock = $1.39 and Conversion = $3.95; 2004: Feedstock = $1.19 and Conversion = $3.08; 2005: Feedstock = $1.24 and Conversion = $2.61; 2006: Feedstock = $1.24 and Conversion = $2.61. The right half of the chart (a vertical dotted line separates the two sides) separates out the conversion technologies with Balance of Plant in red, Distillation and Solids Recovery in light blue, Saccharification and Fermentation in light green, Enzymes in dark green, Prehydrolysis/Treatment in dark blue, and Feedstock in grey: 2007: Feedstock = $1.12, Prehydrolysis/Treatment = $0.89, Enzymes = $0.39, Saccharification and Fermentation = $0.35, Distillation and Solids Recovery = $0.14, and Balance of Plant = $0.77; 2008: Feedstock = $1.04, Prehydrolysis/Treatment = $0.89, Enzymes = $0.38, Saccharification and Fermentation = $0.35, Distillation and Solids Recovery = $0.14, and Balance of Plant = $0.76; 2009: Feedstock = $0.95, Prehydrolysis/Treatment = $0.78, Enzymes = $0.36, Saccharification and Fermentation = $0.33, Distillation and Solids Recovery = $0.13, and Balance of Plant = $0.64; 2010: Feedstock = $0.82, Prehydrolysis/Treatment = $0.64, Enzymes = $0.36, Saccharification and Fermentation = $0.28, Distillation and Solids Recovery = $0.13, and Balance of Plant = $0.54; 2011: Feedstock = $0.76, Prehydrolysis/Treatment = $0.59, Enzymes = $0.34, Saccharification and Fermentation = $0.24, Distillation and Solids Recovery = $0.12, and Balance of Plant = $0.51; 2012: Feedstock = $0.83, Prehydrolysis/Treatment = $0.27, Enzymes = $0.36, Saccharification and Fermentation = $0.18, Distillation and Solids Recovery = $0.12, and Balance of Plant = $0.40. A blue star over the bar for 2012 represents the estimated production cost of first-of-a-kind biochemical cellulosic ethanol facility in 2012.

We focus on biological (fermentative) upgrading of sugars and other components to fuel precursor intermediates and/or bioproducts, making use of organisms to perform the key conversion steps. TEA modeling work done under this pathway includes detailed design, processing, and cost considerations attributed to an organism's metabolic constraints, e.g., anaerobic versus aerobic fermentation, batch versus fed-batch or continuous bioreactor operations, and bioconversion heat and power optimization.

NREL's biochemical conversion analysis program has an established history of conducting detailed TEA modeling of biochemical pathways for more than a decade, both to track R&D progress attributed to BETO Platform research as well as for external partners and stakeholders, across a variety of target products including ethanol, other alcohols, hydrocarbon fuels, and chemical products. This figure provides one example of the Biochemical Analysis project's efforts to track R&D progress under BETO's ethanol program over the course of 10 years, culminating in the successful demonstration of nth-plant cost targets for biochemical ethanol production from corn stover at pilot scale (via biological conversion of sugars). Similar efforts are underway for R&D activities focused on drop-in hydrocarbon fuel production, as well as synthesis of bioproducts derived from cellulosic biomass.

Bar graph showing Hydrogen Sourcing on the x-axis and minimum fuel selling price (MFSP) and greenhouse gas (GHG) emissions on the y-axis (numbered 0 through 7). Blue bars represent MFSP in $/gallon gasoline equivalent (GGE) and red bars represent GHG emissions in kg CO2-eq/GGE. On the left side the bar graphs are labeled 100% External Purchased on the x-axis: MFSP = 4 and GHG Emissions = 6. On the right side the bar graphs are labeled 100% Internal on the x-axis: the In Situ MFSP = 5.5, Gasification MFSP = 4.9, In Situ GHG Emissions = 1.8, and Gasification GHG Emissions = .8. A blue dotted line goes upward, left to right, from the top of the 100% External Purchased MFSP bar to the top of the 100% Internal In Situ MFSP bar. A red dotted line goes downward, left to right, from the top of the 100% External Purchased GHG Emissions bar to the top of the 100% Internal In Situ GHG Emissions bar.

Process modeling and analysis for the catalytic conversion approach may follow a similar processing conversion approach in terms of biomass deconstruction operations that typically may take place initially (although opportunities exist to tailor such operations to meet the needs of the downstream conversion steps), but instead focuses on catalytic upgrading of sugars, sugar derivatives, or other soluble carbon species to hydrocarbon fuels or chemical coproducts. Additionally, opportunities for hybrid pathways exist which may, for example, pursue biological synthesis of an intermediate product followed by catalytic upgrading of the intermediate to a finished fuel, blendstock, and/or coproduct. Research on a number of such pathways is ongoing at NREL and external commercial and research institutions.

One example of TEA modeling work done under this pathway is that we've demonstrated the importance of quantifying tradeoffs between cost and sustainability that could be exhibited, e.g., between catalytic pathways that may enable high carbon yields but at the expense of high hydrogen consumption (in contrast to fermentative approaches, which typically lose more carbon as CO2 but do not require substantial external hydrogen inputs).