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   • Uses
   • How it Works
   • Benefits
   • Limitations
   • Geography
   • Sources

Fossil Fuels

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.

wood chipsHow 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.

Plant Material
scientistResearchers 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.

Type of Biomass

What the Biomass Does

biodiesel (a fuel typically made from soybeans)

a nontoxic alternative to diesel fuel with reduced air emissions

corn stover (leftover stalks, leaves, cobs)

can be burned as a fuel in boilers to heat buildings

yard waste

can be burned and converted into heat or electricity

unused seed corn

burned to fire cement kilns (used to make ceramics)

crop residue (pieces of crop plants remaining after harvest)

burned for grain-drying

switchgrass (a prairie grass typically used to make hay)

reburning fuel in coal-fired cyclone burners to reduce nitrogen oxide (NO) emissions


converted to methane (natural gas)

landfill and wastewater methane

converted to electricity

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
busMany 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.

"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
cornAnother 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.

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.


  1. Alternative Energy Institute. "Biomass." (Online) HTTP://www.altenergy.org. July 2001.
  2. Chariton Valley Biomass Project. "Project Description." (Online) HTTP://www.cvrcd.org/projectdescription.htm. July 2001
  3. Energy Efficiency and Renewable Energy Network (Department of Energy). "Biomass Resources." (Online) HTTP://www.eren.doe.gov/RE/bio_resources.html. July 2001.
  4. Energy Efficiency and Renewable Energy Network (Department of Energy). "Biopower." (Online) HTTP://www.nrel.gov/clean_energy/biopower.html July 2001.
  5. Energy Efficiency and Renewable Energy Network (Department of Energy). "Biofuels." (Online) HTP://www.eren.doe.gov/RE/bio_fuels.html. July 2001.
  6. 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.
  7. 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.
  8. Iowa Department of Energy. "An Introduction to Biomass." (Online) HTTP://www.state.ia.us/dnr/energy/MAIN/renewable/index.html. July 2001.



Oat Hulls Power University
University of Iowa tests using oat hulls instead of coal for cheaper and cleaner energy. More

brown greaseDid 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.

Lean Mean Fuel from a Bean
soy busBeans 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.

IPTV Market to Market Links

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
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