Summer 1998
U.S. Department of Energy
Bioenergy Feedstock Development Program at
Oak Ridge National Laboratory
Energy Crops Forum was published periodically by the Bioenergy
Feedstock Development Program, Environmental Sciences Division, Oak Ridge
National Laboratory, managed by UT-Battelle, LLC., for the U.S. Department of
Energy under Contract No. DE-AC05-00OR22725.
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Table of Contents
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The Bioenergy Feedstock Development Program (BFDP) and its sponsors in the
Department of Energy are developing new energy crops and feedstock supply
systems for the United States. BFDP has also participated in international
biomass feedstock activities under the auspices of the International Energy
Agency (IEA). This issue of Energy Crops Forum describes some of these
efforts.
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The IEA is composed of 24 member countries who have recognized the global
interdependence in energy. Implementing Agreements provide a framework within
which international research collaboration is possible on specific topics. By
working together, duplication of effort can be avoided, costs of research and
technology development are lowered, and more rapid progress toward developing
innovations in energy technology can be made. BFDP has been heavily involved
with the IEA Bioenergy Agreement, which deals with the production, processing,
and use of biomass materials for energy purposes. The program developed under
the Agreement relies on collaboration by national experts from research,
government, and industry. The goal is to realize the use of environmentally
sound and cost-competitive bioenergy on a sustainable basis, providing a
substantial contribution to meeting future energy demands.
The work of the IEA Bioenergy Agreement is carried out through a series of
Tasks. Each Task is led by an Operating Agent and usually consists of multiple
Activities that address specific technical issues. Each country participating
in an Activity contributes toward the organizational infrastructure and usually
supports the participation of subject-matter experts in IEA collaborations.
During 1995–97, there were four active tasks. Task XII, Biomass production,
harvesting and supply, aimed to design and develop cost-effective and
environmentally sound biomass production, harvesting and supply systems for
energy recovery. Task XIII, Biomass utilization, aimed to improve technologies
for efficiently producing energy and chemicals from wood and other biomass
feedstocks. Task XIV, Energy recovery from municipal solid waste (MSW), aimed
to advance the development and deployment of energy recovery from MSW. Task XV,
Greenhouse gas balances of bioenergy systems, aimed to investigate processes
involved in the use of bioenergy systems on a full fuel-cycle basis to
establish overall greenhouse gas balances. Descriptions of Activities, with
strong BFDP participation within some of these Tasks, follow.
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The close-out report for this task identified the major non-technical barriers
as policies, costs, and concerns about the environment. Policy-related issues
came out on top because environmental barriers could possibly be resolved
through public education and cost could be dealt with if policies were stable.
Canada and the United States were most affected by barriers created by the
differential costs between fossil fuels and biomass fuels and the lack of
energy policy equalizing the those costs. Sweden, Denmark, and United Kingdom
were more affected by barriers related to technology transfer, incentives for
getting long-term commitments from biomass fuel suppliers, financing
mechanisms, and environmental issues. Comparisons of energy prices revealed
that some countries have tax policies that partly level the playing field among
competing energy technologies whereas others do not. The task participants
concluded that government intervention will be required to facilitate the
commercialization of biomass energy in most countries and that new policy tools
may be needed.
A new edition of the short-rotation forestry production systems handbook, Handbook
on How to Grow Short Rotation Forests (Ledin, S. and A. Alriksson.1992.
Swedish University of Agricultural Sciences), was produced. The Worldwide Web
version of the Handbook includes Robinia pseudoacacia and Eucalyptus
sections and can found at http://www.abdn.ac.uk/wsrg/ieabioenergy/srfhb.htm. A
search function provides quick access to any part of the book and enables a
user to find information by country or topic. An enhanced version of the
handbook, complete with pictures and videos, is also available on a CD-ROM.
Productions systems studies also examined using willows (Salix) as a
vegetation filter for treatment of sewage water and examined growth responses
with municipal sludge and ash applications. The success of willow filters
varies considerably with the development stage of the plantation and also with
site conditions, but several municipalities have planted willow filtration
stands. Leaching of nitrate appears to be the largest factor limiting the size
of the sewage water dose. Both sludge and ash additions resulted in Salix
stem mass equal to that produced by commercial fertilizers. As a result of
increased pH in the lime and ash treatments, manganese and cadmium mass in
stems decreased. Net accumulation in the topsoil of Cu, Mn, and Ni occurred in
all ash treatments; Zn and Cd accumulation depended on ash source and type.
The coppice research studies undertaken within the frame of the IEA program were
focused on (1) the role of carbohydrates during resprouting in coppice systems
and (2) the effects of N availability on starch resrves in roots and shoots of S.
viminalis. C14 labeling showed when the carbohydrate storages were
built up and when reserve products were used for regrowth and resprouting.
Plants with high nitrogen levels had lower amounts of starch in all tissues
than low- nitrogen plants. The major storage locations for starch were in
roots, stems, and stool in this order. The effect of different harvesting
equipment and techniques was also studied. Harvesting damage effects remained
observable throughout the 3-year period of investigation. Yield differences as
a result of harvest damage were approximately 10 dry tonnes/ha/yr between the
least and most damaged stools. Several papers on this work, by Lisa Sennerby-
Forsse and co-authors, are in press.
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Using many different avenues — workshops, reports, cooperative studies, and
analyses — these projects investigated and characterized the environmental
consequences of intensive biomass production systems, including consideration
of ecological balances, diversity and conservation.
Several workshops were held to develop environmental guidelines for development
of sustainable energy from biomass. One workshop focused on biomass harvesting
and the development of guidelines to achieve sustainable forest management.
During another meeting, best management practices and certification schemes for
environmental sustainability of conventional forestry bioenergy production
systems were reviewed. Example guidelines were presented and discussed from the
perspectives of forestry industry, individual countries, and international
efforts such as the Montreal Process.
A review of issues concerning the environmental sustainability of short-rotation
forestry was also initiated and a template for sustainable forest bioenergy
production systems was developed. This template drew from essential concepts
incorporated in existing guidelines and was intended to be generic enough to
satisfy the requirements of most individual state, company, or international
regulatory structures.
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To characterize and improve planting stock and improve understanding of
physiological, genetic and environmental influences on stock performance,
participants developed laboratory and field experiments and programs in which
clonal and breeding stock was exchanged and evaluated. Molecular genetic
techniques were used to characterize willow and poplar clones. In addition,
several frost hardiness research experiments were undertaken.
In Sweden, two full-sib families of Salix were studied; one family was a
cross between two S. viminalis parents, whereas the other was a
backcross of S. viminalis to a hybrid between S. viminalis and S.
schwerinii. Trees were exposed to growing conditions which consisted of
gradually shortening days and gradually decreasing temperatures. These
conditions induced frost hardiness in both crosses, although the backcross
trees generally displayed greater resistance than did the crosses of pure S.
viminalis. Clonal differences in frost damage within each cross were
highly significant.
At the University of Minnesota, a three-generation pedigree of Populus hybrids
was used to map quantitative trait loci (QTL) for bud set and frost hardiness.
The F2 mapping population was derived from a cross between a northern clone of P.
trichocarpa from Washington and a southern clone of P. deltoides
from Texas. The timing of bud set was measured under three experimental
conditions and the data from all experiments will be used in conjunction with
molecular marker data to map QTL.
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The Systems Studies Activity had two objectives: (1) to investigate nontechnical
barriers to the deployment of biomass production and supply systems and (2) to
enhance and extend existing systems models of bioenergy supply and use. For the
first objective, the Activity focused on existing bioenergy markets. Four
projects were undertaken — a comparative analysis of bioenergy in Sweden and
Austria; a one-day workshop on nontechnical barriers jointly supported by the
Production Systems Activity; the development and testing of a framework for
analyzing barriers and drivers to bioenergy markets; and surveys of wood pellet
users in Sweden, Austria, and the United States. Some of the more interesting
findings concerned the side effects of different policy approaches to promoting
bioenergy. In Sweden, bioenergy, mainly from forestry residues, has been
promoted through carbon taxes that are only applied to the use of fuel for heat
(not electricity). In Austria, bioenergy has been supported by government
grants for building biomass district heating plants. The former approach has
sometimes negatively impacted other industries that also use such forest
residues (e.g., pine oil manufacture). The latter approach has reduced the
incentive to build cost-effective plants. The cost per kWhr of heat did not
decline over time or with the size of the facility. (Roos, A. 1998.
Nontechnical barriers and driving forces to bioenergy market growth in USA,
Austria and Sweden – the role of policy and market structure. pp. 1154-1157. In
Proc. 10th European Conference and Technology Exhibition, Biomass for Energy
and Industry. C.A.R.M.E.N., Rimpar, Germany.)
For the second objective, two projects were undertaken. First, the Activity
worked with the Integrated Bioenergy Systems (IBS) Activity of Task XIII to
enhance the BioEnergy Assessment Model (BEAM). This model considers the entire
bioenergy system from feedstock generation and feedstock preparation through
the conversion process. The model can compare different feedstocks and/or
different conversion technologies in a common format. The Systems Studies
Activity contributed to enhancing the feedstock portion of the model by
developing a coherent set of willow, poplar, and switchgrass production modules
relevant to both the United States and the United Kingdom. The Activity also
developed a pretreatment module for switchgrass. Second, the Activity sponsored
a three-day workshop on modeling bioenergy systems with the objectives of
providing an overview of the types of models used to evaluate bioenergy and
promoting communication among bioenergy modelers. There were nine guest
speakers addressing different types of models used to evaluate different
aspects of bioenergy — ranging from techno- economic models based on the ASPEN
software to linear programming models to develop feedstock supply curves for
the United States. The suite of their papers will be published in an upcoming
volume of the journal Biomass and Bioenergy.
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The focus of this Activity was to develop a computer- based technoeconomic model
in order to better understand integrated bioenergy systems. The model is being
designed to predict performance, costs, and environmental impacts. Individual
modules analyze biomass production, harvesting, conversion, and utilization and
can be linked to form an integrated analysis tool. Several workshops were held
to discuss the underlying assumptions and methodologies used in order to
provide consistent datasets. Industrial interest in the model is high.
Data from the model are also being incorporated into a sustainable process index
(SPI) methodology to determine the relative ecological impacts of various
processes. Environmental factors are quantified in order to compare renewable
and nonrenewable technologies.
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IEA began a new 3-year cycle in 1998 with a major restructuring of the whole
Bioenergy Agreement. Management infrastructure was reduced and many of the
previous tasks were combined. The new Short- Rotation Crops Task combines woody
and herbaceous crop production and harvesting activities as well as pest and
disease, stock improvement, and systems studies. Lynn Wright, of the BFDP, is
representing the U.S. The crops of most interest to the participants include
switchgrass, reed canary grass, Miscanthus, willows, poplars, black locust, and
eucalyptus. Representatives met on June 2-5, 1998, in Uppsala, Sweden, to plan
for the future.
Concerns expressed by several participants over market introduction problems
affected the selection of topics for focus by the Short-Rotation Task
participants. The topics receiving the most votes were: (1) full-scale
implementation strategies, (2) integrated water quality improvement and
bioenergy production, and (3) sustainable management. The group decided that
recognition of crop protection (pest and disease) issues would be included
within studies of sustainable management. Other key topics embedded in the
first two topics are cost-reduction and co-production of products.
The participants narrowed the task objectives to the following: (1) to stimulate
the full-scale implementation of energy crops in the participating countries;
(2) to strengthen contacts and co-operation among scientists and biomass
producers, machine developers, entrepreneurs, and end-users as well as between
participating countries; and (3) to select the most urgent research and
development areas to recommend for cooperative efforts.
The group also decided to prepare a “vision statement” about the potential role
of short-rotation crops in addressing energy, global climate change, and water
quality issues that would hopefully be applicable to all participating
countries and be useful for public education activities.
One of the most interesting presentations at the Uppsala meeting was made by an
entrepreneur from the Swedish Company, Salix Maskiner AB, who described a
project that couples water quality improvement with producing feedstocks for
central heat and power production. Company staff assisted farmers in a small
community to plant willows strategically between food production fields and
small streams which drain into a lake used for recreational purposes by local
residents. Water quality in the lake has been visibly improved; consequently,
residents are willing to pay a higher price for the heat and power produced by
combustion of the harvested willows. Because each willow field is relatively
small, the small planting and harvesting equipment developed by Salix Maskiner
AB operates efficiently in the system.
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As do so many other organizations, the IEA has a presence on the Internet. The
IEA home page can be found at http://www.iea.org/. The Bioenergy Task page is
at http://www.fri.cri.nz/ieabioenergy/home.htm
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