The Benefits of Biodiesel
National Benefits
Biodiesel fuel is made from vegetable oils or animal fats. Unlike petroleum diesel, made from crude oil,
these oil sources are renewable. The use of biodiesel fuel also contributes far less greenhouse gas
emissions because the CO2 released when it is burned in an engine was removed from the atmosphere
during the previous growing season – resulting in no net change in atmospheric CO2.
Biodiesel can also have important economic and security benefits. The United States imports about $1
billion/day in foreign petroleum oil. In contrast, biodiesel is made from domestic vegetable oils, reducing
our dependence on imported fuels. Foreign trade and national security improve as reliance on foreign
oil declines. Export of biodiesel can also be a source of income for the United States.
The use of domestic vegetable oil and animal fat can also benefit farmers as it creates higher incomes
from crop and animal products. Finally, biodiesel can even be made from waste fryer oil and rendering
wastes, turning these low-value waste products into high-value transportation fuel.
Environmental Benefits
In addition to dramatically-reduced greenhouse gas emissions, biodiesel provides other air quality
benefits (NBB, undated):
1.
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6.
Smog or ozone forming potential is 50% less than diesel fuel emissions.
Sulfur dioxides and sulfates (primary ingredients for acid rain) are essentially eliminated.
48% decrease of carbon monoxide emissions.
47% decrease particulate matter (soot)
67% decrease of hydrocarbons (which contribute to localized formations of ozone and smog)
Nitrogen Oxides virtually stay the same as diesel fuel but, the reduction in sulfur allows
nitrogen-removing control technologies to be installed. These nitrogen-removing technologies
cannot be installed when conventional diesel fuel is used. In addition, some companies have
created nitrogen oxide-removing additives that can reduce the emissions.
7. Reduced carcinogenic chemicals such as polycyclic aromatic hydrocarbons (PAHs) and nitrated
polycyclic aromatic hydrocarbons (nPAHs). The reduction is approximately 75% when compared
to diesel fuel.
Biodiesel also reduces environmental harm from the production of diesel fuel. Exploration for and
extraction of crude oil can damage habitat and cause water and air pollution. The recent oil spill in the
Gulf of Mexico is only one example. Refining and distributing diesel fuel also produces air, , and land
pollution. In contrast, biodiesel is relatively non-toxic and is biodegradable. However, production of
biodiesel involves the use of several toxic chemicals and must be carefully controlled in order to prevent
environmental contamination.
Diesel Vehicle Benefits
Biodiesel fuel can be used in diesel engines with little or no modification. Its performance is considered
equivalent or superior in most respects as compared to diesel fuel. Biodiesel has a higher cetane rating
(equivalent to octane rating in gasoline) has similar performance in terms of fuel consumption, torque,
horse power, and haulage rates. Biodiesel also has greater lubricity, reducing engine wear and reducing
maintenance downtime for trucks.
However, biodiesel also has some properties that can cause problems in diesel vehicles if not properly
managed. Though all diesel fuels gel at cold temperatures, biodiesel tends to gel at higher temperatures
preventing vehicle operation in cold weather. To overcome this, biodiesel is typically blended with
petroleum diesel, or anti-gelling additives may be used. In addition, biodiesel has good detergent
properties. While this can be beneficial in keeping fuel lines and fuel injectors clean, it can cause fuel
filter clogging when vehicles are initially switched from standard diesel to biodiesel as the biodiesel
tends to mobilize the dirt that has build up in the fuel system from years of diesel use.
Illinois State University Benefits
Illinois State University generates approximately 6,000 gallons of waste fryer oil from its dining centers
each year. The goal of the ISU Student Biodiesel Project is to convert this waste into fuel for campus
diesel vehicles (such as the campus recycling truck, “Big Blue”). The Project produces a variety of
benefits for ISU and its students:
1. Increasing the value to waste fryer oil from animal feed to transportation fuel.
2. Reducing greenhouse gas and other emissions from campus.
3. Reducing the amount of diesel fuel stored and use on campus, reducing employee and
environmental exposures.
4. Provide students with research and bioenergy production experience that can expand career
opportunities.
5. Educating local schools on the importance of renewable energy
References
NBB (undated) Biodiesel Emissions, National Biodiesel Board,
www.biodiesel.org/pdf_files/fuelfactsheets/emissions.pdf)