feedstock

When the lignocellulosic biofuels industry reaches maturity and many types of biomass sources become economically viable, management of multiple feedstock supplies – that vary in their yields, density (tons per unit area), harvest window, storage and seasonal costs, storage losses, transport distance to the production plant – will become increasingly important for the success of individual enterprises. The manager’s feedstock procurement problem is modeled as a multi-period sequence problem to account for dynamic management over time. The case is illustrated with a hypothetical 53 million annual US gallon cellulosic ethanol plant located in south west Kansas that requires approximately 700,000 metric dry tons of biomass. The problem is framed over 40 quarters (10 years), where the production manager minimizes cumulative costs by choosing the land acreage that has to be contracted with for corn stover collection, or dedicated energy production and the amount of biomass stored for off-season. The sensitivity of feedstock costs to changes in yield patterns, harvesting and transport costs, seasonal costs and the extent of area available for feedstock procurement are studied. The outputs of the model include expected feedstock cost and optimal mix of feedstocks used by the cellulosic ethanol plant every year. The problem is coded and solved using GAMS software. The analysis demonstrates how the feedstock choice affects the resulting raw material cost for cellulosic ethanol production, and how the optimal combination varies with two types of feedstocks (annual and perennial).

This database contains current and historical official USDA data on production, supply and distribution of agricultural commodities for the United States and key producing and consuming countries.

FAOSTAT provides time-series and cross sectional data relating to food and agriculture for some 200 countries.

The national version of FAOSTAT, CountrySTAT, is being developed and implemented in a number of target countries, primarily in sub-saharan Africa. It will offer a two-way data exchange facility between countries and FAO as well as a facility to store data at the national and sub-national levels.

Meeting the Energy Independence and Security Act (EISA) renewable fuels goals requires development
of a large sustainable domestic supply of diverse biomass feedstocks. Macroalgae, also known as
seaweed, could be a potential contributor toward this goal. This resource would be grown in marine
waters under U.S. jurisdiction and would not compete with existing land-based energy crops.
Very little analysis has been done on this resource to date. This report provides information needed for an
initial assessment of the development of macroalgae as a feedstock for the biofuels industry.
The findings suggest that the marine biomass resource potential for the United States is very high based
on the surface area of the marine waters of the U.S. and rates of commercial macroalgae production in
other parts of the world. However, macroalgae cultivation for fuels production is likely a long term effort.
Analysis of the available data showed that considerable scale up in cultivation over current world-wide
production and improvements in processing throughout the supply chain are needed.
Despite the high resource potential, the United States does not currently have a macroalgae production
industry and would have to develop this capability. In order to meet current renewable fuels goals, the
scale of the effort would have to be high in comparison with activity in other parts of the world. For
example, replacing 1% of the domestic gasoline supply with macroalgae would require annual production
rates about ten and one-half times current worldwide production. This could be accomplished through
cultivation on 10,895 km2 of ocean surface, based on current rates of production reported for the
international macroalgae cultivation industry. Advances in cultivation technology already being tested
could potentially increase production from three to ten fold with a corresponding decrease in the area
needed for cultivation to meet specified production goals. While it is no surprise that the cost estimates to
produce fuel from macroalgae are currently high, it should be noted that this is based on a limited amount
of available data and that production costs for macroalgae can benefit from increased efficiency and scale.
A thorough analysis is warranted due to the size of this biomass resource and the need to consider all
potential sources of feedstock to meet current biomass production goals. Understanding how to harness
this untapped biomass resource will require additional research and development. A detailed assessment
of environmental resources, cultivation and harvesting technology, conversion to fuels, connectivity with
existing energy supply chains, and the associated economic and life cycle analyses will facilitate
evaluation of this potentially important biomass resource.

This report, generally referred to as the Billion-Ton Study or 2005 BTS, is an estimate of “potential” biomass available within the contiguous United States based on assumptions about inventory production capacity, availability, and technology.

The United States Department of Agriculture (USDA) and the United States Department of Energy (DOE) both place high importance on developing resources and conversion technologies for producing fuels, chemicals and power from biomass. The two departments are working together on several aspects of bioenergy. This report is the third to be produced from joint collaboration. This and other reports can be found at: http://www1.eere.energy.gov/library/default.aspx?page=1.

The website for biomass feedstock research sponsored by the DOE’s Office of Energy Efficiency and Renewable Energy Bioenergy Technologies Office (BETO) can be found at: http://web.ornl.gov/sci/transportation/research/bioenergy/. More general information about BETO's feedstock research program can be found at: http://www.energy.gov/eere/bioenergy/biomass-feedstocks.

The website for research and development sponsored by the USDA Forest Service can be found at: http://www.fs.fed.us/research/.
The website for bioenergy research sponsored by the USDA Agricultural Research Service can be found at: http:// www.ars.usda.gov/research/programs/programs.htm?NP_CODE=307.

Transgenic modification of plants is a key enabling technology for developing sustainable biofeedstocks for biofuels production. Regulatory decisions and the wider acceptance and development of transgenic biofeedstock crops are considered from the context of science-based risk assessment. The risk assessment paradigm for transgenic biofeedstock crops is fundamentally no different from that of current generation transgenic crops, except that the focus of the assessment must consider the unique attributes of a given biofeedstock crop and its environmental release. For currently envisioned biofeedstock crops, particular emphasis in risk assessment will be given to characterization of altered metabolic profiles and their implications relative to non-target environmental effects and food safety; weediness and invasiveness when plants are modified for abiotic stress tolerance or are domesticated; and aggregate risk when plants are platforms for multi-product production. Robust risk assessments for transgenic biofeedstock crops are case-specific, initiated through problem formulation, and use tiered approaches for risk characterization.

Interest in liquid biofuels production and use has increased worldwide as part of government policies to address the growing scarcity and riskiness of petroleum use, and, at least in theory, to help mitigate adverse global climate change. The existing biofuels markets are dominated by U.S. ethanol production based on cornstarch, Brazilian ethanol production based on sugarcane, and European biodiesel production based on rapeseed oil. Other promising efforts have included programs to shift toward the production and use of biofuels based on residues and waste materials from the agricultural and forestry sectors, and perennial grasses, such as switchgrass and miscanthus—so-called cellulosic ethanol. This article reviews these efforts and the recent literature in the context of ecological economics and sustainability science. Several common dimensions for sustainable biofuels are discussed: scale (resource assessment, land availability, and land use practices); efficiency (economic and energy); equity (geographic distribution of resources and the “food versus fuel” debate); socio-economic issues; and environmental effects and emissions. Recent proposals have been made for the development of sustainable biofuels criteria, culminating in standards released in Sweden in 2008 and a draft report from the international Roundtable on Sustainable Biofuels. These criteria hold promise for accelerating a shift away from unsustainable biofuels based on grain, such as corn, and toward possible sustainable feedstock and production practices that may be able to meet a variety of social, economic, and environmental sustainability criteria.

Soaring global food prices are threatening to push more poor people back below the poverty line; this will probably become aggravated by the serious challenge that increasing population and climate changes are posing for food security. There is growing evidence that human activities involving fossil fuel consumption and land use are contributing to greenhouse gas emissions and consequently changing the climate worldwide. The finite nature of fossil fuel reserves is causing concern about energy security and there is a growing interest in the use of renewable energy sources such as biofuels. There is growing concern regarding the fact that biofuels are currently produced from food crops, thereby leading to an undesirable competition for their use as food and feed. Nevertheless, biofuels can be produced from other feedstocks such as lingo-cellulose from perennial grasses, forestry and vegetable waste. Biofuel energy content should not be exceeded by that of the fossil fuel invested in its production to ensure that it is energetically sustainable; however, biofuels must also be economically competitive and environmentally acceptable. Climate change and biofuels are challenging FAO efforts aimed at eradicating hunger worldwide by the next decade. Given that current crops used in biofuel production have not been domesticated for this purpose, transgenic technology can offer an enormous contribution towards improving biofuel crops' environmental and economic performance. The present paper critically presents some relevant relationships between biofuels, food security and transgenic plant technology.

A dry-grind ethanol from corn process analysis is performed. After defining a complete model of the process, a pinch technology analysis is carried out to optimise energy and water demands. The so-defined base case is then discussed in terms of production costs and process profitability. A detailed sensitivity analysis on the most important process and financial variables is carried out. The possibility to adopt different alternatives for heat and power generation combined to the process is evaluated.

In this article the environmental and socio-economical impacts of the production of ethanol from sugarcane in the state of São Paulo (Brazil) are evaluated. Subsequently, an attempt is made to determine to what extent these impacts are a bottleneck for a sustainable and certified ethanol production. Seventeen environmental and socio-economic areas of concern are analysed. Four parameters are used to evaluate if an area of concern is a bottleneck: (1) the importance of the area of concern, based on the severity of the impact and the frequency of which an aspect is mentioned in the literature as an area of concern, (2) the availability of indicators and criteria, (3) the necessity of improvement strategies to reach compliance with Brazilian and/or (inter) national legislation, standards, guidelines and sustainability criteria, and (4) the impact of these improvement strategies on the costs and potential of ethanol production. Fourteen areas of concern are classified as a minor or medium bottleneck. For 7 areas of concern the additional costs to avoid or reduce undesirable effects have been calculated at ⩽+10% for each area of concern. Due to higher yields and overlapping costs the total additional production costs of compliance with various environmental and socio-economic criteria are about +36%. This study also shows that the energy input to output ratio can be increased and the greenhouse gas emissions reduced by increasing the ethanol production per tonne cane and by increasing the use of sugarcane waste for electricity production. A major bottleneck for a sustainable and certified production is the increase in cane production and the possible impacts on biodiversity and the competition with food production. Genetically modified cane is presently being developed, but is at this moment not (yet) applied. Both a ban on and the allowance of the use of genetically modified cane could become a major bottleneck considering the potentially large benefits and disadvantages, that are both highly uncertain at this moment. The approach demonstrated in this report provides a useful framework for the development of a practically applicable certification system, but further monitoring and research is required to reduce gaps in knowledge in combination with stakeholder consultation (particularly with respect to the three bottlenecks identified in this article).