resources: Wisconsin Harvesting Roadside Grass for Energy
In the biomass energy resources game, people are coming up
with creative methods of harvesting grass for local energy production.
Wisconsin, a project that evaluated the feasibility of harvesting road side grassy biomass as an alternative energy was conducted, and had some real
Check out the video on the
right for more information on this environmentally friendly, and money saving method of harvesting bio-energy.
Benefits of Using
Grass as Bioenergy
Historically, most biomass heating fuels, such as wood chips,
wood pellets, and cord wood came from the forest products industry.
over the past 15 years, growing crops (both herbaceous and woody) as an alternative energy
has gained widespread appeal, and perennial grasses such as Switch grass,
Miscanthus, and Reed Canary grass present exciting new biomass energy resources.
Perennial grasses are now being used as a solid fuel in
co-fired coal power plants as well as a choice feedstock for such
advanced bio-fuels as cellulosic ethanol.
Despite this focus on generating
electricity and producing liquid fuels, perennial grasses can also be pressed
into pellets, briquettes, cubes, and used as a heating source to replace or complement
fuels made from wood fibers.
Perennial grasses are one of the best biomass energy resources, because it is easy to grow,
harvest, and process.
Grasses store vast amounts of
carbon in root systems and soil, and are available in a wide
range of geographies, climates, and soil types.
Grasses can be grown on marginal lands ill-suited for
continuous row crop production and in open rural land currently not in agricultural
They yield more biomass per acre, and require far fewer inputs in
comparison to annual crops that require more diesel, fertilizer, and pesticides.
Additionally, perennial grasses grown for energy can provide
a new revenue source for farmers and land owners.
Bio energy compatible grasses also create important water quality and wildlife benefits.
Grasses and other agriculturally
produced crops can be grown easily, quickly, and in large acreages and volumes.
This can help increase the amount of biomass energy resources in a particular
A recent study determined that one acre of farmland is
capable of producing an average annual yield of herbaceous biomass sufficient
to meet the yearly space, and water heating needs of an average home.
The most promising areas for development of a grass energy
industry are the north central and northeastern regions of the United States,
where there is sufficient agricultural land and heating costs are high due to long
As an alternative energy for heating, grasses have Btu
levels approximately 95 percent of wood.
High density grass fuel is competitive against oil, natural gas, propane, and electricity.
No one grass species can be grown in all regions
and climates, but the most broadly considered grasses for energy
production are Switch grass (and other native prairie grasses such as Big
Bluestem and Prairie Cord grass).
Miscanthus, a super high-yielding crop, has gained much attention
and is now being studied.
Reed Canary grass is naturally present and high
yielding in wet, marginal areas, but it is also invasive—choking out other
native wetland species, so its use as an alternative energy crop is more
Each has its own benefits and disadvantages as biomass energy resources.
Facts about Which Grass to Use
When considering which bio energy compatible grass to use, the first thing to consider
is the yield per acre in any given micro-climate or soil type, since these factors
influence conversion of the grass to a useable alternative energy.
Another consideration is the mineral and ash content of a given
grass on a given plot, which may affect the value of the crop as a high density
fuel for thermal applications.
Harvest windows are
influenced by local climates.
Grasses grown for alternative energy are managed for biomass
yield rather than forage or nutritive quality. In fact, lower nutrient levels
(nitrogen, sulfur, chlorine, etc.) may improve fuel quality and reduce
The growth and yield of the grass is
highly dependent on soil conditions, moisture, fertility, weed control, and timing
During the growing season, modest use of fertilizers may be needed to
maintain soil fertility and improve crop yields.
Careful attention must be paid
to ensure that crops are not over fertilized for risk of leaking surplus
nutrients into ground and water ways.
Warm season grasses like Switch grass are widely adaptive, but require strict weed control during the first year of growth, so fall and winter grasses do not overwhelm its growth.
Switch grass should be harvested once per year, generally after
frost, using standard haying equipment.
Grasses cut in the fall and left over winter
are far lower in yield but have been shown to weed out potassium and chlorine,
two minerals that may create issues during combustion.
Miscanthus can be difficult to establish and should be harvested
late in the fall, using standard farm equipment (corn silage choppers, balers).
Conclusion: Using Grass an Alternative Energy is a Cool Idea!