Fall 1991
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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Welcome to the premiere issue of Energy Crops Forum (ECF), a newsletter
devoted to fostering improved communications among a world-wide research
community, policymakers, industry, entrepreneurs, and landowners. Our goal for
this edition is to present a taste of things to come. Future issues will
contain articles about research projects, operational experiences,
environmental concerns, and policy analyses. Suggestions and contributions are
invited and should be sent to the address below.
Energy Crops Forum is sponsored by the U.S. Department of Energy's
Biofuels System Division, ECF and will be published three times a year
by the Biofuels Feedstock Development Program, Oak Ridge National Laboratory.
Let us know if any of your colleagues would also be interested in being on the
mailing list.
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Within the next 20 to 40 years, millions of acres of cropland in the United
States could support the production of crops for energy. Rows of short-rotation
woody crops (SRWC) would grow alongside corn and sorghum on flat cropland, and
lush fields of grass would thrive on gently sloping hillsides. This vision is
held by program managers at the U.S. Department of Energy, scientists at Oak
Ridge National Laboratory, and many researchers around the world. Exact
predictions are impossible, but the United States appears to have the
productive capacity to support significant biomass-based energy production.
Preliminary analyses estimate 35-70 million acres could become available for
energy crops without impairing the country's ability to meet other agricultural
demands.
Energy crops of the future will differ from today's food and energy crops.
Although starch, sugar, and oilseed crops will remain a part of the energy crop
mix, whole-plant biomass crops (trees and grasses) are expected to predominate.
The amount of useful energy fixed on a per acre basis will increase. Product
losses will decrease and economic advantages of whole-plant use will be
enhanced as more efficient biomass energy conversion systems become available.
Energy crops will be selected on the basis of their ability to meet stringent
criteria. First and foremost, high yet cost-effective yields must be achieved
in environmentally sustainable management systems. Crops must be able to grow
productively despite climatic and biological stresses. They must be inherently
pest resistant, requiring very little pesticide. Species, varieties, and
management systems must be developed to promote efficient nutrient recycling.
Genetically superior varieties may be cloned to capture their high production
potential. However, a large number of different clones and clonal mixtures will
be planted to increase diversity and reduce risks from pests and diseases.
Cropping patterns and cropping systems that further reduce environmental risks
will be developed, and plantings will be carefully planned to improve local
environmental quality.
This vision will not be possible without work. It requires a solid base of
research and cooperation among researchers, policymakers, and private sector
entrepreneurs. Making this vision a reality would be a significant step toward
a sustainable, renewable future, a goal well worth working for.
Lynn Wright, Deputy Program Manager and Janet Cushman, Program Manager, Biofuels
Feedstock Development Program
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Many environmental policy groups are aware of the potentially positive role
energy crops and biomass fuels can play in controlling greenhouse gases (such
as CO2) and improving air quality. Although climate change and air
quality issues drive this interest, concern is also growing for improved
biodiversity, sustainability, and wildlife habitat, especially for threatened
and endangered species on both local and national scales. Facts about the
environmental impact of energy crops are scarce. In FY 1992 the U.S. Department
of Energy through Oak Ridge National Laboratory will begin to address this
deficiency by initiating research on the interaction of energy crops with the
environment in cooperation with environmental groups and existing R&D
projects.
A recent review of the rather limited literature on wildlife, habitat, and
sustainability of SRWC, combined with anecdotal observations and discussions
with environmental groups has illuminated some important issues and results. By
the second or third year of growth, for example, SRWC stands temporarily take
on species composition characteristics of old field succession with juvenile
trees and a grassy understory. By the fifth year, fast-growing SRWC stands more
closely approximate hardwood forests than old fields or conifer monocultures.
The wildlife species diversity in SRWC stands appears to improve by contact
with native forests. Data collection on the effects of habitat structure and
landscape patterns on wildlife will be high on the research agenda.
Chemical use and erosion associated with energy crops are also of major concern.
Comparisons with annual food crops are generally favorable, but energy crops
may also be planted on land now in perennial fodder crops and pasture. R&D
recommendations for complete weed control in SRWC stands and relatively high
fertilization rates in both woody and herbaceous stands may need operational
modifications to meet environmental concerns. Use of soil-stabilizing ground
covers such as nitrogen-fixing legumes and strip herbiciding instead of
broadcast herbiciding could reduce chemical use, improve sustainability by
reducing erosion, and improve habitat quality during plantation establishment.
Forest clear-cutting issues are inappropriately linked with SRWC. Sufficient
excess agricultural land is available so that forest land is not required for
energy crop production. No forests will be cleared for SRWC plantings. A
related issue may be the public response to the harvesting of energy crops once
they have provided improved habitat conditions for wildlife. Careful early
planning with local wildlife agencies and conservation and sportsman's groups
will be important.
The positive effects on greenhouse gases and air quality from the use of energy
crops for fuel should remain an important part of the environmental equation
and will be more clearly documented in the future.
Jack Ranney, Environmental Task Manager, Biofuels Feedstock Development Program
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Most forestry researchers would be proud to claim that in just 12 years their
genetic hybridization and silviculture research had generated 30,000 seedlings,
of which 2,000 selected clones had been placed in 25 separate field trials. But
for the scientific team that began in 1978 with the joint efforts of Reinhard
Stettler, a forest geneticist at the University of Washington (UW), and Paul
Heilman, a silviculturist at Washington State University (WSU), these
hybridization accomplishments and field trial networks only hint at their
considerable scientific progress and technology transfer success.
Initially, most of their research focused on crossing various Populus species
with the native black cottonwood (P. trichocarpa) to create new
interspecific hybrids better suited for short-rotation forestry. When a group
of P. trichocarpa x P. deltoides (TxD) hybrids demonstrated 100
to 200% growth improvements in yield trials, naturally the response was to
probe for reasons why the plants performed so differently. Since then research
has expanded into many areas, including work on root morphology, seedling
nutrition, leaf anatomy, whole-plant physiology, cellular biology, and
mechanisms of pest resistance.
Today the poplar research performed at UW and WSU includes 11 principal
investigators, their co-workers, and funding in excess of $1.6 million from
federal, state, and private sources. Exciting developments are occurring in all
phases of the research and technology transfer. Two-year growth in 1990 field
trials suggested, for example, that new hybrids, P. trichocarpa x P.
nigra (TxN), appear promising for rapid growth in dry areas in eastern
Washington and Oregon. Some of the top TxD hybrids demonstrated high
performance in both eastern and western Washington, especially when irrigation
was applied. Evaluations of specific gravity show ranges of 0.27 to 0.45 among
different hybrid clones, thus offering excellent opportunities for selecting
high-performance clones with high energy content. An extension bulletin on
growing hybrid poplars in the Pacific Northwest has just been published (see
Publications of Interest).
The mapping of the Populus genome using molecular markers is a new effort
under way at UW. This mapping allows previous information relating to plant
morphology and physiology, wood quality, and pest resistance to be linked to
specific DNA sites within the genome, possibly leading to direct selection of
the genes responsible for such traits. Along with the continued efforts in
basic Populus biology, this type of research should increase hybrid
productivity.
This interdisciplinary group of researchers has worked on many facets of poplar
biology. They have also demonstrated how genetic and environmental manipulation
can be effectively orchestrated toward specific goals related to improving
biomass yields in short-rotation woody crops. Several companies are
contributing money to the research. Hybrids produced by UW are now being
planted commercially by James River Corporation and 25,000 to 50,000 acres may
be planted in the near future by Boise Cascade and Scott Paper companies.
Gerald Tuskan, Woody Crops Task Manager, and Lynn Wright, Biofuels Feedstock
Development Program
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The first commercial harvest of short-rotation woody crops (SRWC) in the United
States is taking place this year on James River Corporation land in the Pacific
Northwest. The trees, mostly hybrid poplar clones developed by the University
of Washington, were planted by the former Crown Zellerbach Corporation in 1983
on the Lower Columbia River Fiber Farm (LCRFF), a 10,000-acre project on
previously planted fertile bottomland. For logistical reasons, the first
plantations were located adjacent to an existing papermill. Luckily, the site
has proven to be an excellent choice for the production of hybrid poplars.
The supervisor of the LCRFF, Don Rice, stresses there are five keys to success
in growing SRWC.
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Suitable lands for establishing the crops must be used.
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Improved genetic materials must be available to justify the use of intensified
culture techniques and high-quality land.
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Agricultural production techniques must be applied to the planting and tending
of the trees.
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Specialized harvesting and processing systems must be used.
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Planting, tending, and harvesting approaches must be sensitive to and
compatible with the environment.
One possible reason that James River has been so successful in adapting
agricultural production methods to tree growing is that the company started
with personnel trained in farm management rather than forest management. James
River also took advantage of the expertise of university researchers who were
developing production techniques for the new hybrid poplar clones. Even so, a
learning curve of 3 to 5 years was required to arrive at the best management
practices for the LCRFF site. James River continues to have a good relationship
with and be supportive of academic research, even though the company has
invested in its own genetic- improvement and cultural-management research
programs. This cooperation assures that the corporation will have access to
multiple resources to address any problems that may arise.
Although specialized harvesting and processing systems are not commercially
available, James River's solution is likely to result in success. The company
has hired a qualified harvest equipment engineer and conducted field research
to determine the best available options.
James River personnel are learning by experience and experimentation how to
manage an operation that is not only productive but also harmonious with the
environment. James River appears committed to growing SRWC in a way that
maximizes profit and minimizes environmental impact. This successful operation
may serve as a model for commercializing SRWC in other parts of the country.
Lynn Wright
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An energy crop field day focusing on short-rotation management of cottonwoods,
hybrid poplars, and alders in the Pacific Northwest was held on July 10, 1991,
in Yelm, Washington. The event, organized by Connie Harrington and Dean DeBell
of the U.S. Forest Service Pacific Northwest Station, attracted approximately
80 people from diverse environments: 7 wood products companies, 2 newspapers, a
mining company, local and state government agencies, several landowners, and
university and forest service scientists, including some from Canada and
Europe.
The well-organized event offered a profusion of informative handouts and
knowledgeable speakers presented technical information on red alder cottonwood
and hybrid poplar silviculture; fertilizer trials; and genetics research.
Tours of the hybrid poplars plantations were a high point. The observed growth
in the various experiments was impressive and illustrated the possibilities
offered by short-rotation woody crops using genetically superior plant
material.
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On November 15, 1990, a significant revision of the Clean Air Act (CAA) was
signed into law. CAA is designed to improve air quality through reducing smog,
air toxics and volatile organic compounds (VOCs), carbon monoxide (CO), acid
precipitation (sulfur dioxide [SO2] and nitrogen oxides [NOx]),
and chlorofluorocarbons (CFCs). A number of provisions of the revised CAA will
affect the production of biomass and fuels derived from biomass.
Ozone, the main ingredient in smog, is formed by the reaction of volatile
organic compounds (VOCs) with NOx in the presence of sunlight. CAA
reduces allowable VOCs in gasoline and mandates reduced NOx emissions. In areas
where ozone exceeds Environmental Protection Agency (EPA) standards, gasoline
containing 2% by weight (wt%) of oxygen will be required by January 1, 1995.
This could affect 22% of the gasoline sold.
The major source of carbon monoxide is the transportation sector. By November 1,
1992, nonattainment areas (accounting for 27% of the gasoline sold) will
require gasoline with 2.7 wt% oxygen during certain winter months. In the most
serious CO nonattainment areas (e.g., Los Angeles, Houston, and New York),
gasoline with 3.1 wt% oxygen may be required.
Provisions to reduce ozone formation and CO emissions require oxygenated fuels
such as ethanol, methanol, ethyl tertiary butyl ether (ETBE), and methyl
tertiary butyl ether (MTBE) that can be derived from biomass. The presence of
oxygen in gasoline reduces VOCs and CO emissions. Ethanol, methanol, ETBE, and
MTBE contain 35, 50, 18, and 16 wt% oxygen, respectively. These fuels are also
good octane sources.
Electric utilities burning coal are the primary sources of SO2 emissions.
CAA provisions to reduce SO2 emissions make biomass fuels more
attractive to utilities. Under regulations to be developed by EPA by May 15,
1992, renewable fuels (including biomass) will qualify for additional emissions
allocations for acid rain, primarily through SO2 reductions (Sect.
404). To also reduce overall SO2 emissions, sulfur content of diesel
fuel is limited to 0.05%.
Some sections of the CAA specifically affect biomass and biomass-derived fuels.
For instance, Section 231 specifically directs research on substituting alcohol
esters of high erucic acid rapeseed oil for diesel. Other sections may have
indirect impacts. The prescribed burning used in site preparation for
production of some crops may eventually require operating permits (Title V).
Although the effects of the CAA on biomass commercialization are uncertain, the
Act mandates a study (Sect. 808) to calculate "environmental benefits of
renewable energy." Regulations are to be developed that reward renewable energy
technologies for these environmental benefits.
Anthony Turhollow, Economics Task Manager, Biofuels Feedstock Development Program
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The following materials are available from Washington State University
Cooperative Extension - Lewis County, P.O. Box 708, Chehalis, WA 98532,
(206)748-9121:
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A study of marketing prospects for hybrid cottonwood grown in southwest
Washington by private landowners. 1990. 82 p. $6.
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Intensive culture of high yield hybrid poplar plantations in the Pacific
Northwest. 1989. 47 p. $2.50.
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Economic analysis of short rotation hybrid poplar plantations. 1989. 7 p.
$0.25.
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