Some diesel engines need their veggies, too!
by Robert W. Varney
We’ve known for years that
eating vegetables can help us stay healthy, but who would guess
that vegetables could also be good for diesel engines? Manufactured
from vegetable oils, primarily soy beans, biodiesel is a safe,
biodegradable, renewable fuel that offers a reduction in many
air pollutants when used in ordinary diesel engines and furnaces.
Biodiesel has widespread benefits.
It helps farmers, creating a new market for agricultural products;
reduces U.S. dependence on foreign oil; burns more cleanly than
regular diesel fuel; and creates jobs in sectors that support
the growing and developing infrastructure of the biodiesel market.
Biodiesel is becoming more widely available with its latest propulsion
coming from new tax incentives aimed at closing the gap between
petroleum diesel fuel and biodiesel.
Biodiesel is usually blended
with regular diesel fuel. Blends of 20 percent biodiesel with
80 percent petroleum diesel (B20) can be used in unmodified diesel
engines or furnaces. Biodiesel can be used in its pure form (B100),
but may require engine modifications to avoid maintenance and
performance problems. Because pure biodiesel can gel in cold weather,
B100 may not be suitable for use in cold climates. The National
Biodiesel Board reports that more than 400 major fleets nationwide
are using biodiesel in their vehicles. Many institutions are also
beginning to heat their buildings with biodiesel blended with
Advantages & Considerations
Biodiesel has some unique environmental
attributes. Perhaps the most interesting is that biodiesel, as
compared to petroleum diesel, produces significantly less carbon
dioxide, a climate change gas. According to the U.S. Department
of Energy, biodiesel production and use, in comparison to petroleum
diesel, produces 78 percent less carbon dioxide emissions. Carbon
dioxide is released when biodiesel made from soybeans is combusted,
but the annual production of soybean crops helps remove carbon
dioxide from the atmosphere.
In addition to helping reduce
emissions of carbon dioxide, biodiesel also has other significant
environmental benefits. EPA estimates that B20 reduces emissions
of particulate matter and carbon monoxide by about 10 percent
and hydrocarbons by more than 20 percent. Unfortunately, using
B20 in a diesel engine can increase emissions of smog-causing
nitrogen oxides by about 2 percent. Using higher blends of biodiesel
can help further reduce most emissions, but will result in a greater
increase in emissions of nitrogen oxides. EPA estimates that B100
increases nitrogen oxides emissions by 10 percent. Some biodiesel
produces more nitrogen oxides than others, but some additives
have shown promise in counteracting the increase.
Biodiesel can also be blended
with oil used for heating, generating similar reductions in emissions
of particulate matter, carbon monoxide, and hydrocarbons. Interestingly,
due to different combustion temperatures between stationary oil
burners and diesel vehicles, emissions of nitrogen oxides do not
increase when biodiesel is used in furnaces.
While biodiesel has some impressive environmental benefits,
currently it has two key drawbacks - cost and convenience. B20
costs about $.20 more per gallon than regular diesel fuel and
B100 costs about $1 more per gallon. A large percentage of this
cost difference comes from transportation and distribution costs.
As new tax incentives take effect and the number of biodiesel
refueling stations increases, the cost differential between biodiesel
and regular diesel may decrease over time.
Under the new law, federal excise
tax credit is offered to biodiesel blenders - entities that mix
pure biodiesel with regular petroleum diesel fuel. The credit
amounts to one cent per percentage point of biodiesel made from
first-use oils (such as soybean oil) and a half-cent per percentage
of biodiesel made from other sources (such as recycled cooking
oil). In other words, an excise tax credit of $1.00 per gallon
is offered to certified biodiesel blenders of refined B100 biodiesel.
The intent of the tax incentives is that blenders will pass along
the cost savings to consumers through competitive pricing practices.
Fortunately, the infrastructure needed to get biodiesel
to consumers is emerging at a rapid pace. Currently, there are
several suppliers of biodiesel, approximately twenty blenders
and distributors of biodiesel, and a similar number of biodiesel
retail fueling sites in New England. The National Biodiesel Board
tracks suppliers, distributors, and retail providers of biodiesel.
For the current list visit www.biodiesel.org.
Some organizations with capital
and commitment to the environment are building their own infrastructure
to support biodiesel use. For example, Harvard University spent
$60,000 to build a campus fueling station in Boston. Harvard is
currently fueling its fleet of 48 diesel vehicles, including 8
shuttle buses, with B20. Despite record low temperatures in 2004,
Harvard reports no problems with the fuel or the vehicles. Because
of the success of this project, Harvard is exploring other applications
of B20 use at its facilities.
Using biodiesel may be more challenging
for consumers who are not in close proximity to biodiesel refineries
or fueling stations. For example, Vermont Law School in South
Royalton, committed to using B20 to heat their library because
of the environmental benefits attributable to biodiesel use. A
spokesperson from the school reports that they are paying a $1.00
per gallon premium for heating the building with biodiesel and
that it has been difficult to coordinate delivery of the fuel
with a local distributor. In spite of that, the school plans to
continue to use biodiesel and is hopeful that the new tax incentives
enjoyed by biodiesel blenders will be passed on to consumers in
Where in New England?
Biodiesel is being used throughout New England in a
number of locations including: Connecticut Department of Transportation;
L.L. Bean, Inc.; Maine Department of Transportation; City of Bangor,
Maine; Harvard University; UMASS Amherst; NSTA;, Cities of Medford,
Cambridge, and Brookline; Mount Cranmore Ski Resort; New Hamshire
Department of Transportation; Keene State College and the City
of Keene; Pease Air Force Base; Warwick Rhode Island; University
of Vermont; Vermont Law School; Sugarbush Ski Resort; and Vermont
For information, see: www.epa.gov/ne/eco/diesel/retrofits.html