The Seattle Times Newspapers In Education presents
IMAGINETOMORROW
What are biofuels?
Biofuels are a sustainable fuel source made from
organic substances that were recently living, like plants
and microorganisms. Unlike fossil fuels — coal, oil and
gas — which come from organic matter created long
ago, biofuels can be replenished.
•
Sugars include starch and cellulose. Starch stored in corn can be fermented into ethanol, which is blended into gasoline. Cellulose found in wood waste, switchgrass and crop residues can be converted into ethanol and denser alcohols.
What issues should be considered when
developing biofuels?
•
Food vs. fuel: How can we grow fuel crops without compromising food production?
A biofuel can be a solid biomass (think of burning wood
or pellets), a liquid (such as ethanol added to gasoline)
or a biogas (such as methane derived from a waste
facility). Biofuels can be used to generate heat and
electricity, prepare meals and enable transportation.
•
Total release of CO2: If you take into account fertilizers, fuel transport and infrastructure needs,
do biofuels remain carbon neutral?
•
Ecological balance: How is the environment affected when we generate or collect biomass?
Why are biofuels better for the planet?
•
Supply: Is biomass available in sufficient quantity to support our energy needs?
•
Price: Can biofuels compete with fossil fuels
economically?
Mankind has burned fossil fuels since the Industrial
Revolution, releasing carbon dioxide into the
atmosphere. Since carbon dioxide causes the Earth’s
temperature to warm, reducing carbon dioxide
emissions is critical to managing climate change.
That’s where biofuels come in. While they do release
carbon dioxide, they release less than fossil fuels. When
fossil fuels are burned, they transfer carbon dioxide
that had been “locked up” in the ground directly into
the air. In contrast, biofuels release carbon dioxide
that was recently absorbed from the air. So the net
carbon dioxide increase in the atmosphere from burning
biofuels is typically less than from fossil fuels.
Where do biofuels come from?
Primary sources of biofuels are crop plants like corn
and soy, reused cooking oil, and gas generated from
anaerobic microorganisms. Researchers are developing
other sources of biomass for use as transportation fuel,
such as agricultural and timber harvest waste and algae. There are also crops grown specifically for use as
biofuels — among them switchgrass and camelina —
which thrive on land not suitable for food production.
Finding a solution
Students from Cascade High School in
Cascade, Idaho, designed a photosynthetic
bioreactor to remove carbon dioxide created
by fossil-fuel-fired power plants, utilize
nutrients from wastewater and produce
biodiesel. They succeeded and won the
Biofuels Challenge in the 2012 Imagine
Tomorrow competition.
Take the challenge
Imagine new ways to utilize biofuels. The future is in
your hands!
Classroom exercises
•
Fermentation systems to generate biofuels rely on feedstocks such as corn and wood waste. Demonstrate a method to refine a biological product to generate combustible fuel for aircraft.
•
Growing biofuel crops often raises “food vs. fuel”
concerns. Survey a farmer’s co-op to determine regional feelings about growth of fuel crops. Find out if fuel crops are displacing food crops in your region.
•
What oil- or sugar-based waste products could be converted into biofuel? Make a list.
•
Look up “switchgrass” or “camelina.” What makes these plants suited for conversion into biofuel?
MAY 17–19, 2013
Washington State University, Pullman
The Imagine Tomorrow competition
challenges 9th through 12th graders to
seek innovative solutions to global energy
challenges. Students with interests in all
subjects — art and design, engineering,
social sciences, and sciences — vie for
more than $100,000 in cash prizes for
themselves and their schools. Register
and compete for free! Find out more at
imagine.wsu.edu.
Join us next week as we explore ways to build a better world by changing behavior.
To register for NIE, visit us
at seattletimes.com/nie
or call 206/652-6290.
091211323_01
The demand for clean energy, the threat of climate
change and the need to transition to an economy based
on alternatives to fossil fuels are tough issues that we
all must address. A partial solution to the world’s energy
concerns may be found in biofuels.
Biofuels for transportation are made predominantly
from two types of chemicals: oils (lipids) and sugars
(polysaccharides).
• Oils are generated from plants, animal fats and algae. Biodiesel, for instance, is often made from discarded cooking oil.
Photo by WSU
Photo Services
A BETTER WORLD
THROUGH BIOFUELS
WEEK 1