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This article analyzes rail transportation costs of products that have similar physical properties as densified biomass and biofuel. The results of this cost analysis are useful to understand the relationship and quantify the impact of a number of factors on rail transportation costs of denisfied biomass and biofuel. These results will be beneficial and help evaluate the economic feasibility of high-volume and long-haul transportation of biomass and biofuel. High-volume and long-haul rail transportation of biomass is a viable transportation option for biofuel plants, and for coal plants which consider biomass co-firing. Using rail optimizes costs, and optimizes greenhouse gas (GHG) emissions due to transportation. Increasing bioenergy production would consequently result in lower GHG emissions due to displacing fossil fuels. To estimate rail transportation costs we use the carload waybill data, provided by Department of Transportation’s Surface Transportation Board for products such as grain and liquid type commodities for 2009 and 2011. We used regression analysis to quantify the relationship between variable transportation unit cost ($/ton) and car type, shipment size, rail movement type, commodity type, etc. The results indicate that: (a) transportation costs for liquid is $2.26/ton–$5.45/ton higher than grain type commodity; (b) transportation costs in 2011 were $1.68/ton–$5.59/ton higher than 2009; (c) transportation costs for single car shipments are $3.6/ton–$6.68/ton higher than transportation costs for multiple car shipments of grains; (d) transportation costs for multiple car shipments are $8.9/ton and $17.15/ton higher than transportation costs for unit train shipments of grains.

The 2011 US Billion-Ton Update estimates that by 2030 there will be enough agricultural and forest resources to sustainably provide at least one billion dry tons of biomass annually, enough to displace approximately 30% of the country's current petroleum consumption. A portion of these resources are inaccessible at current cost targets with conventional feedstock supply systems because of their remoteness or low yields. Reliable analyses and projections of US biofuels production depend on assumptions about the supply system and biorefinery capacity, which, in turn, depend upon economic value, feedstock logistics, and sustainability. A cross-functional team has examined combinations of advances in feedstock supply systems and biorefinery capacities with rigorous design information, improved crop yield and agronomic practices, and improved estimates of sustainable biomass availability. A previous report on biochemical refinery capacity noted that under advanced feedstock logistic supply systems that include depots and pre-processing operations there are cost advantages that support larger biorefineries up to 10 000 DMT/day facilities compared to the smaller 2000 DMT/day facilities. This report focuses on analyzing conventional versus advanced depot biomass supply systems for a thermochemical conversion and refinery sizing based on woody biomass. The results of this analysis demonstrate that the economies of scalemore » enabled by advanced logistics offsets much of the added logistics costs from additional depot processing and transportation, resulting in a small overall increase to the minimum ethanol selling price compared to the conventional logistic supply system. While the overall costs do increase slightly for the advanced logistic supply systems, the ability to mitigate moisture and ash in the system will improve the storage and conversion processes. In addition, being able to draw on feedstocks from further distances will decrease the risk of biomass supply to the conversion facility.« less

To meet Energy Independence and Security Act (EISA) cellulosic biofuel mandates, the United States will require an annual domestic supply of about 242 million Mg of biomass by 2022. To improve the feedstock logistics of lignocellulosic biofuels in order to access available biomass resources from areas with varying yields, commodity systems have been proposed and designed to deliver quality-controlled biomass feedstocks at preprocessing “depots”. Preprocessing depots densify and stabilize the biomass prior to long-distance transport and delivery to centralized biorefineries. The logistics of biomass commodity supply chains could introduce spatially variable environmental impacts into the biofuel life cycle due to needing to harvest, move, and preprocess biomass from multiple distances that have variable spatial density. This study examines the uncertainty in greenhouse gas (GHG) emissions of corn stover logistics within a bio-ethanol supply chain in the state of Kansas, where sustainable biomass supply varies spatially. Two scenarios were evaluated each having a different number of depots of varying capacity and location within Kansas relative to a central commodity-receiving biorefinery to test GHG emissions uncertainty. The first scenario sited four preprocessing depots evenly across the state of Kansas but within the vicinity of counties having high biomass supply density. The second scenario located five depots based on the shortest depot-to-biorefinery rail distance and biomass availability. The logistics supply chain consists of corn stover harvest, collection and storage, feedstock transport from field to biomass preprocessing depot, preprocessing depot operations, and commodity transport from the biomass preprocessing depot to the biorefinery. Monte Carlo simulation was used to estimate the spatial uncertainty in the feedstock logistics gate-to-gate sequence. Within the logistics supply chain GHG emissions are most sensitive to the transport of the densified biomass, which introduces the highest variability (0.2–13 g CO 2 e/MJ) to life cycle GHG emissions. Moreover, depending upon the biomass availability and its spatial density and surrounding transportation infrastructure (road and rail), logistics can increase the variability in life cycle environmental impacts for lignocellulosic biofuels. Within Kansas, life cycle GHG emissions could range from 24 g CO 2 e/MJ to 41 g CO 2 e/MJ depending upon the location, size and number of preprocessing depots constructed. However, this range can be minimized through optimizing the siting of preprocessing depots where ample rail infrastructure exists to supply biomass commodity to a regional biorefinery supply system.

Over 9 million dairy cows generate an estimated 226 billion kg of wet manure annually in the USA. To help mitigate dairy greenhouse gas (GHG) emissions associated with the degradation of this organic-rich waste, manure can be processed via anaerobic digestion (AD) to methane and ultimately electricity. This potential value of AD has generated high-level dairy-industry support for broad-scale technology deployment; however, on-the-ground AD realization has been impeded by process stability/reliability concerns and poor economics. Considering these challenges but recognizing that AD represents a fundamentally sound manure-management approach, an interdisciplinary research team has completed proof-of-concept investigations on an integrated process that will concurrently improve manure management economics and reduce dairy GHG emissions. The integrated processes center on a two-stage fermentation/AD system that can generate methane quantity/quality comparable to conventional single-stage AD. Molecular level investigations confirm that the AD is highly enriched with a unique and synergistic microbial population which yielded a more resilient and stable process. Beyond AD, algae grown on nitrogen/phosphorus-rich AD supernatant in a photobioreactor yielded biomass concentrations approaching 1.0 g L–1; despite an apparent growth lag/inhibition associated with excess organic acids and ammonia, algae growth was significant. Environmental life cycle assessment (LCA) demonstrated that the two-stage AD configuration coupled with algae production can reduce GHG emissions by approximately 60% as compared with a traditional anaerobic lagoon. The end result is a manure-management platform that can increase US dairy viability and sustainability. Ongoing investigations are aimed at process refinement with an ultimate commercialization goal. © 2013 Society of Chemical Industry and John Wiley & Sons, Ltd

Using densified biomass to produce biofuels has the potential to reduce the cost of delivering biomass to biorefineries. Densified biomass has physical properties similar to grain, and therefore, the transportation system in support of delivering densified biomass to a biorenery is expected to emulate the current grain transportation system. By analyzing transportation costs for products like grain and woodchips, this paper identifies the main factors that impact the delivery cost of densified biomass and quantifies those factors’ impact on transportation costs. This paper provides a transportation-cost analysis which will aid the design and management of biofuel supply chains. This evaluation is very important because the expensive logistics and transportation costs are one of the major barriers slowing development in this industry. Regression analysis indicates that transportation costs for densified biomass will be impacted by transportation distance, volume shipped, transportation mode used, and shipment destination, just to name a few. Since biomass production is concentrated in the Midwestern United States, a biorefinery’s shipments will probably come from that region. For shipments from the Midwest to the Southeast US, barge transportation, if available, is the least expensive transportation mode. If barge is not available, then unit trains are the least expensive mode for distances longer than 161 km (100 miles). For shipments from the Midwest to the West US, unit trains are the least expensive transportation mode for distances over 338 km (210 miles). For shorter distances, truck is the least expensive transportation mode for densified biomass.

Biomass is increasingly being considered as a feedstock to provide a clean and renewable source of energy in the form of both liquid fuels and electric power. In the United States, the biofuels and biopower industries are regulated by different policies and have different drivers, which impact the maximum price the industries are willing to pay for biomass. This article describes a dynamic computer simulation model that analyzes future behavior of bioenergy feedstock markets given policy and technical options. The model simulates the long-term dynamics of these markets by treating advanced biomass feedstocks as a commodity and projecting the total demand of each industry, as well as the market price over time. The model is used for an analysis of the United States bioenergy feedstock market that projects supply, demand, and market price given three independent buyers: domestic biopower, domestic biofuels, and foreign exports. With base-case assumptions, the biofuels industry is able to dominate the market and meet the federal Renewable Fuel Standard (RFS) targets for advanced biofuels. Further analyses suggest that United States bioenergy studies should include estimates of export demand in their projections, and that GHG-limiting policy would partially shield both industries from export dominance.

The Department of Energy’s (DOE) Bioenergy Technology Office (BETO) aims at developing and deploying technologies to transform renewable biomass resources into commercially viable, high-performance biofuels, bioproducts and biopower through public and private partnerships (DOE, 2015). BETO and its national laboratory teams conduct in-depth techno-economic assessments (TEA) of technologies to produce biofuels. These assessments evaluate feedstock production, logistics of transporting the feedstock, and conversion of the feedstock to biofuel. There are two general types of TEAs. A design case is a TEA that outlines a target case for a particular biofuel pathway. It enables identification of data gaps and research and development needs, and provides goals and targets against which technology progress is assessed. On the other hand, a state of technology (SOT) analysis assesses progress within and across relevant technology areas based on actual experimental results relative to technical targets and cost goals from design cases, and includes technical, economic, and environmental criteria as available.

Straw and corn stover can be used to produce ethanol by enzymatic hydrolysis and fermentation, or syndiesel by oxygen gasification and Fischer Tropsch (FT) reaction. FT has a higher processing cost and a higher energy yield of liquid transportation fuel. We analyze the cost of produced liquid fuel as a function of the field cost of biomass. At 80 $ t−1 (dry basis) a crossover point is reached. Below this value, the cost of producing energy as ethanol is lower; above this value, FT syndiesel is lower. However, the crossover point occurs at a very high field cost of biomass, more than 5.50 $ GJ−1, and ethanol plants are less capital intense than FT and hence have a smaller economic size. For both reasons ethanol is likely to be the preferred processing alternative.

Abating the dependence of the United States on foreign oil by reducing oil consumption and increasing biofuels usage will have far-reaching global effects. These include reduced greenhouse gas emissions and an increased demand for biofuel feedstocks. To support this increased demand, cellulosic feedstock production and conversion to biofuels (e.g. ethanol, butanol) is being aggressively researched. Thus far, research has primarily focused on optimizing feedstock production and ethanol conversion, with less attention given to the feedstock supply chain required to meet cost, quality, and quantity goals. This supply chain comprises a series of unit operations from feedstock harvest to feeding the conversion process. Our objectives in this review are (i) to summarize the peer-reviewed literature on harvest-to-reactor throat variables affecting feedstock composition and conversion to ethanol; (ii) to identify knowledge gaps; and (iii) to recommend future steps.

We propose that minimum incremental cost per unit of greenhouse gas (GHG) reduction, in essence the carbon credit required to economically sustain a renewable energy plant, is the most appropriate social criterion for choosing from a myriad of alternatives. The application of this criterion is illustrated for four processing alternatives for straw/corn stover: production of power by direct combustion and biomass integrated gasification and combined cycle (BIGCC), and production of transportation fuel via lignocellulosic ethanol and Fischer Tropsch (FT) syndiesel. Ethanol requires a lower carbon credit than FT, and direct combustion a lower credit than BIGCC. For comparing processes that make a different form of end use energy, in this study ethanol vs. electrical power via direct combustion, the lowest carbon credit depends on the relative values of the two energy forms. When power is 70$ MW h−1, ethanol production has a lower required carbon credit at oil prices greater than 600$ t−1 (80$ bbl−1).

The LCA emissions from four renewable energy routes that convert straw/corn stover into usable energy are examined. The conversion options studied are ethanol by fermentation, syndiesel by oxygen gasification followed by Fischer Tropsch synthesis, and electricity by either direct combustion or biomass integrated gasification and combined cycle (BIGCC). The greenhouse gas (GHG) emissions of these four options are evaluated, drawing on a range of studies, and compared to the conventional technology they would replace in a western North American setting. The net avoided GHG emissions for the four energy conversion processes calculated relative to a “business as usual” case are 830 g CO2e/kWh for direct combustion, 839 g CO2e/kWh for BIGCC, 2,060 g CO2e/L for ethanol production, and 2,440 g CO2e/L for FT synthesis of syndiesel. The largest impact on avoided emissions arises from substitution of biomass for fossil fuel. Relative to this, the impact of emissions from processing of fossil fuel, e.g., refining of...