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Biomass is
organic matter that has stored energy through photosynthesis. For
example, a tree uses photosynthesis to store energy in its leaves
and trunk. The tree is biomass. It can be burned to release the energy
in the form of heat.
 How
do you turn trash into treasure? Pollution into power? Think biomass!
Everything from crops left in the field to weedy trees, from animal
waste to humans’ garbage, can be recycled and transformed into
useable energy. Biomass is a very broad term covering a wide variety
of materials that can be seen as energy resources. Since the sun’s
energy is absorbed by all living things; humans, animals, and especially
plants, a lot of materials we see as leftovers are really storehouses
of energy. Explore more about exciting new ways to tap into that
energy storehouse called biomass.
Uses
Plant
Material
 Researchers
are developing many different processes to release and convert the
energy stored in biomass. Much of the current effort focuses on
plant material biomass. Some common examples are wood chips, switchgrass,
corn
stover, unused seed corn, and yard waste. All of these materials
can be used as "fuels" for heating, transportation, or
producing electricity.
Uses for
Biomass
There are many
ways we can use biomass to provide us with useful energy.
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Type
of Biomass
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What
the Biomass Does
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biodiesel
(a fuel typically made from soybeans)
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a nontoxic
alternative to diesel fuel with reduced air emissions
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corn stover
(leftover stalks, leaves, cobs)
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can be
burned as a fuel in boilers to heat buildings
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yard waste
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can be
burned and converted into heat or electricity
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unused
seed corn
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burned
to fire cement kilns (used to make ceramics)
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crop residue
(pieces of crop plants remaining after harvest)
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burned
for grain-drying
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switchgrass
(a prairie grass typically used to make hay)
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reburning
fuel in coal-fired cyclone burners to reduce nitrogen oxide
(NO) emissions
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manure
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converted
to methane (natural gas)
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landfill
and wastewater methane
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converted
to electricity
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How
it Works
Biomass Produces Heat
The most common processes
developed so far use combustion to release energy. Just like coal
is burned to produce power, biomass can be burned too. For example,
leftover cornstalks (corn stover) can be burned to heat water into
steam. The steam turns a turbine
that spins a generator
to produce electricity. Another process, called gasification, superheats
plant material into a gaseous state. The gas can then be used to
turn a turbine to drive a generator, producing electricity. Some
power plants are "co-firing," burning biomass with coal,
to cut down on emissions
and consumption of fossil fuels.
Biomass
Could Replace Fossil Fuels
 Many
plant materials can be turned into fuels or fuel additives for transportation.
Corn and sugarcane are used to produce ethanol, a widely used gasoline
additive. Soybeans can be turned into a diesel fuel to run buses,
trucks, or cars. Adaptations to the fuels could also make them suitable
for home heating.
Benefits
"Net
Gain of Zero"
A big benefit to replacing
part or all of fossil fuels with biomass is the environmental impact.
Fossil fuels contribute many harmful emissions to the environment.
Burning biomass creates what experts call a "net gain of zero."
The small amount of emissions put into the atmosphere by burning
biomass are offset by the amount of CO2
that was absorbed by the biomass while it was growing. So while
the overall amount of emissions in the atmosphere isn't reduced,
they aren't increased either. It’s a closed
cycle—a net gain of zero.
Turning
Waste into a Resource
 Another
biomass benefit is economic. Using biomass wrings out every drop
of profit from a crop. By collecting the corn stover that is usually
left on the ground as waste, and turning it into a fuel, the farmer
has another crop to sell. In addition to traditional crops, farmers
can grow "energy" crops like switchgrass, perfect for
power production. These "energy" crops add to the value
of a farm by utilizing land that may not be suitable to grow traditional
crops.
Limitations
Untested
 The
main limitation of biomass is that it is still under development.
While ethanol is used as a gas substitute, trial projects are looking
at how biomass can be used on a larger scale. Until the processes
that unleash the potential energy stored in biomass are more developed
and efficient, this important resource will remain underutilized.
Reduce
Emissions?
The emissions associated
with burning biomass could be viewed as a limitation as well. If
the goal is to have clean nonpolluting energy resources, biomass
comes closer than traditional fossil fuels, but still doesn’t
live up to the standard set by other renewables
that contribute no emissions.
Geographical
Considerations
 Most
regions have access to biomass in varying levels. Biomass is one
of Iowa’s richest resources because the state has a lot of
agriculture-related business. One study estimates that 406 trillion
BTUs of biomass energy could be produced in Iowa without reducing
the amount of land currently dedicated to conventional crops. That
amounts to almost 40% of Iowa’s energy consumption. While other
areas may not have as much biomass as Iowa, every community creates
waste. Recovering the energy trapped within different types of waste
could provide biomass energy for nearly everyone.
Sources
- Alternative
Energy Institute. "Biomass." (Online) HTTP://www.altenergy.org.
July 2001.
- Chariton
Valley Biomass Project. "Project Description." (Online) HTTP://www.cvrcd.org/projectdescription.htm.
July 2001
- Energy Efficiency
and Renewable Energy Network (Department of Energy). "Biomass
Resources." (Online) HTTP://www.eren.doe.gov/RE/bio_resources.html.
July 2001.
- Energy Efficiency
and Renewable Energy Network (Department of Energy). "Biopower."
(Online) HTTP://www.nrel.gov/clean_energy/biopower.html July 2001.
- Energy Efficiency
and Renewable Energy Network (Department of Energy). "Biofuels."
(Online) HTP://www.eren.doe.gov/RE/bio_fuels.html.
July 2001.
- Energy Efficiency
and Renewable Energy Network (Department of Energy). "Biobased
Chemicals and Materials." (Online) HTTP://www.eren.doe.gov/RE/bio_chemicals.html.
July 2001.
- Energy Efficiency
and Renewable Energy Network (Department of Energy). "Integrated
Bioenergy Systems and Assessment." (Online) HTTP://www.eren.doe.gov/RE/bio_integrated.html.
July 2001.
- Iowa Department
of Energy. "An Introduction to Biomass." (Online) HTTP://www.state.ia.us/dnr/energy/MAIN/renewable/index.html.
July 2001.
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Oat
Hulls Power University
University of
Iowa tests using oat hulls instead of coal for cheaper and cleaner
energy. More
BECON
 Did
you know that the grease restaurants use to fry your french fries
can fuel a car? More
Switching
to Switchgrass
 It
started as a "wild" idea. Taking switchgrass, a wild grass
that once grew all across southern Iowa, and turning it into a cash
crop. More
Lean Mean
Fuel from a Bean
 Beans
are a well-known source of gas, now they’re a source for fuel!
More
Biomass Statistics
 Can
you back that up with Numbers? Explore these biomass statistics.
More
IPTV Market to Market Links
Biodiesel
In its first year of operation the USDA claims its bioenergy program
has increased production of ethanol by more than 140 millon gallons
and encouraged the additional output of 6.4 million gallons of biodiesel
fuel.
Soy
Diesel
The U.S. Senate is considering an energy bill that would make it
a national requirement to blend ethanol with gasoline.
Ethanol
could get boost from demise of MTBE
The petroleum based fuel additive was originally seen as beneficial
because it reduces fuel emissions and boosts octane levels. But
worries about the oxygenate arose when groundwater in California
was found to be contaminated by m-t-b-e.
Ethanol
Faces Fight in California
Last week the USDA was touting the benefits of bio-based fuels.
The department implemented a broad plan to encourage its agencies
to begin using biodiesel and ethanol fuels in fleet vehicles.
Biodiesel
Gets Boost from USDA
For the past two years, the government has been testing a mixture
of 20-percent soybean oil and 80-percent diesel, commonly known
as "b-20 Biodiesel," in about 150 vehicles at USDA’s
Agricultural Research Center in Beltsville, Maryland. – Powering
everything from tractors to tour buses on biodiesel.
PBS NewsHour
Online Links
What is carbon sequestration? Carbon sequestration is when we capture
carbon that would normally be released into the atmosphere and hold
it in long term storage. Find
out more
Web Links
Ethanol
What is ethanol? How is it made? Who can answer
all the questions I have about ethanol?
History
of Ethanol
Did you know ethanol was first used in 1876?
700
dairy cows help generate power for 20 homes
700 dairy cows to generate up to 130 kilowatts of electricity every
day, enough to power 20 homes a day
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