Technical Handbook for Marine Biodiesel
In Recreational Boats
by Randall von Wedel, Ph.D. CytoCulture International, Inc. Point
Richmond, CA
Second Edition April 22, 1999 Marine Biodiesel and Education
Project for San Francisco Bay and Northern California Prepared
for the National Renewable Energy Laboratory U.S. Department of
Energy Subcontract No. ACG-7-16688-01 under Prime Contract No. DE-AC36-83CH10093
Biodiesel:
Fuel Additive Made from Vegetable Oil
Biodiesel
is Produced by a Transesterification Process
Niche Market for
Biodiesel: Sailboats with Diesel Engines
Recommended
Blending Ratios for Biodiesel
Emissions
Reductions with Biodiesel
Lower Hydrocarbon
Emissions
Smoke and Soot Reductions
Carbon Monoxide Emissions
Polyaromatic
Hydrocarbons
Nitrogen Oxides
Biodiesel
Helps Reduce Greenhouse Gasses
Positive
Energy Balance
Lower
Impact on Marine Environment
Comparatively
Low Toxicity to Marine Plants and Animals
Low
Solubility and High Biodegradation Rate
Biodegradability
in the Aquatic Environment
Spills
of Biodiesel Can Still Harm the Environment
Engine Performance: Mechanical
Advantages
Lubricity Properties
Heat of Combustion
Properties
Power Differences
Fuel Consumption
Differences
Engine Seals,
Gaskets and Hoses
Warranties
and Engine Manufacturer Endorsements
Safety
and Aesthetic Advantages of Biodiesel
No Noxious
Fumes / No Explosive Vapors
Storage Conditions
for Biodiesel
More Information
on Biodiesel
Biodiesel Producers
in America (With Additional Links)
Biodiesel
from Recycled Cooking Oil
Biodiesel
as a "Mainstream" Alternative Fuel
Pricing and Availability
Learning
More About Marine Biodiesel (With Additional Links)
References
Appendices and
Schematic of Transesterification Process
Technical Handbook for Marine
Biodiesel
This handbook has been prepared to provide practical information
on Biodiesel to owners of recreational boats powered with diesel
engines. The report summarizes research work and field observations
collected over the past five years from the U.S. and Europe. The
handbook is intended to be relatively comprehensive without being
overly detailed. References are cited to guide the reader in pursuing
specific topics in more depth. The appendices contain support documentation
and articles on marine Biodiesel.
BIODIESEL:
Fuel Additive made from Vegetable Oil
Biodiesel is a clean-burning diesel fuel additive produced from
soybean and other vegetable oils instead of petroleum. Biodiesel
is marketed in California for use in marine compression ignition
(diesel) engines to enhance engine combustion performance, improve
engine lubrication, and reduce air and water pollution caused by
the exhaust. Biodiesel blends operate in diesel engines, from light
to heavy-duty, just like petroleum diesel fuel. No engine conversions
are required at all, unless an engine has old fuel lines.
Biodiesel and a 20% blend of Biodiesel in petroleum diesel are
DOE-designated alternative fuels. Biodiesel is registered as a fuel
additive with the Environmental Protection Agency (EPA). Biodiesel
and the 20% blend meet clean diesel standards established by the
California Air Resources Board (CARB), particularly since the Biodiesel
contains no sulfur and no aromatics. The National Biodiesel Board
maintains specifications for Biodiesel and has worked with the American
Society for Testing and Materials (ASTM) to develop a provisional
ASTM standard for Biodiesel production in the U.S.. In 1998, Biodiesel
as a 20% blend ("B-20") with petroleum diesel was designated an
"alternative fuel" under the Energy Policy Act. This designation
allows government fleet services to purchase the B-20 blend for
operation in normal diesel vehicles and receive credit for those
vehicles equivalent to other DOE-approved multi-fuel vehicles.
As a result, Biodiesel can now compete with other alternative fuels
and clean-air options for urban transit fleets and government vehicles
across the country. For the marine market, this DOE designation
should encourage more Biodiesel production and, eventually, lower
prices for consumers.
Biodiesel
is Produced from Vegetable Oils by a Process called Transesterification
(see Appendix for schematic
of process)
Biodiesel is produced from vegetable oils by converting the triglyceride
oils to methyl (or ethyl) esters with a process known as transesterification.
The transesterification process reacts alcohol with the oil to release
three "ester chains" from the glycerin backbone of each triglyceride.
The reaction requires heat and an strong base catalyst (e.g., hydroxide
or lye), to achieve complete conversion of the vegetable oil into
the separated esters and glycerin. The glycerin can be further purified
for sale to the pharmaceutical and cosmetic industries. The mono-alkyl
esters become the Biodiesel, with one-eighth the viscosity of the
original vegetable oil. Each ester chain, usually 18 carbons in
length for soy esters, retains two oxygen atoms forming the "ester"
and giving the product its unique combustion qualities as an oxygenated
vegetable based fuel. Biodiesel is nearly 10% oxygen by weight.
Petroleum diesel, in contrast, is made up of hundreds of different
hydrocarbon chains (roughly in the range of 14-18 carbons in length),
with residues of sulfur and crude oil remaining. Diesel fuel sold
today, even "low sulfur, low aromatic" diesel, contains 20-24% aromatics
(benzene, toluene, xylenes, etc.) which are toxic, volatile compounds
responsible for the fire/health hazards and pollution associated
with petroleum diesel.
Niche Market for Biodiesel:
Sailboats with Auxiliary Diesel Engines
Recreational sailboats powered by auxiliary diesel engines have
proven to be a reliable and high profile market for Biodiesel. In
1997, CytoCulture surveyed 100 recreational boaters in the San Francisco
Bay area and found that 97% of the vessels using Biodiesel from
1993 to 1997 were sailboats. Most of the boats were in the 30 to
50 foot range, and most had smaller diesel engines (12-50 HP) that
consumed relatively little fuel. Sailboaters tend to be more conscious
of environmental concerns, they are sensitive to smoke and odor
from engine exhaust, and they are more inclined than power boaters
to pay for premium diesel fuel since they typically consume only
10-50 gallons a year.
Future marine markets in which the benefits of using Biodiesel
would outweigh the costs include charter boats, water taxis, dive
boats, small ferries, government boats and research vessels.
There should be particular emphasis on using Biodiesel in boats
operating on lakes, rivers and confined bays that are more sensitive
to air and water pollution.
Aside from sailing with the wind, vegetable oil Biodiesel is the
easiest, cleanest and most efficient transformation of solar energy
to produce kinetic energy for mechanical power in boats.
Recommended
Blending Ratios for Biodiesel in Boat Fuel
Biodiesel mixes easily with diesel as a fuel additive for use in
blends of up to 20% with regular petroleum diesel. Add 5 gallons
(one 5-gallon container) of Biodiesel to every 20 gallons of petrodiesel
to achieve a 20% blend, or use the blending chart printed on the
container back label. Biodiesel mixes quickly with petrodiesel once
the boat is moving. Biodiesel is a little heavier than the petroleum
with has a specific gravity of 0.87 compared to 0.79-0.80 typical
of reformulated petrodiesels.
Higher concentrations, up to 100% (neat) Biodiesel, are used in
Europe to operate diesel engines in boats and vehicles with good
performance results and excellent emissions reductions. However,
until new Federal and State laws defining diesel fuel specifications
are mandated to accommodate the unique properties of vegetable methyl
esters, Biodiesel will only be sold as an additive for use in boat
engines at ratios not to exceed 20%. In France, all diesel
sold for vehicle fuel in the entire country ranges from 1% up to
5% rapeseed Biodiesel in a blend and some urban buses routinely
operate on a 30% blend. In Germany, where the price of Biodiesel
(tax exempt) is similar to petroleum diesel (with taxes), over 350
fuel stations offer Biodiesel for sale to motorists and Biodiesel
is used in tour boats on their lakes.
EMISSIONS REDUCTIONS
WITH BIODIESEL
Since Biodiesel is made entirely from vegetable oil, it does not
contain any sulfur, aromatic hydrocarbons, metals or crude oil residues.
The absence of sulfur means a reduction in the formation of acid
rain by sulfate emissions which generate sulfuric acid in our atmosphere.
The reduced sulfur in the blend will also decrease the levels of
corrosive sulfuric acid accumulating in the engine crankcase oil
over time.
The lack of toxic and carcinogenic aromatics (benzene, toluene
and xylene) in Biodiesel means the fuel mixture combustion gases
will have reduced impact on human health and the environment. The
high cetane rating of Biodiesel (ranges from 49 to 62) is another
measure of the additive's ability to improve combustion efficiency.
Unfortunately, current "low aromatic, low sulfur" diesel in California
still contains 20 to 25% aromatics because the oil companies have
been allowed waivers by the state to "reformulate" their diesel
fuels and reduce emissions by adding "cetane enhancers" to lower
emissions to levels equivalent to 10% aromatics. An engine running
on 100% Biodiesel would have NO aromatic emissions and the Biodiesel
would be much safer to store and handle. In addition, Biodiesel
blends have reduced emissions of polyaromatic hydrocarbons, another
group of potentially carcinogenic substances found in petroleum.
Lower Hydrocarbon Emissions
As an oxygenated vegetable hydrocarbon, Biodiesel itself burns
cleanly, but it also improves the efficiency of combustion in blends
with petroleum fuel. As a result of cleaner emissions, there will
be reduced air and water pollution from boats operated on Biodiesel
blends. At a 20% Biodiesel blend, there will be a noticeable change
in the odor and smoke in the exhaust. Older engines should also
emit less soot under load and less carbon black during startup.
Independent research programs in Europe and the U.S. have shown
that Biodiesel in a 20 percent blend with petroleum diesel created
a significant reduction in visible smoke and odor. The studies documented
the reduction in hydrocarbons, carbon monoxide and particulate matter.
Biodiesel is comprised of vegetable oil methyl esters, that is,
they are hydrocarbon chains of the original vegetable oil that have
been chemically split off from the naturally occurring "triglycerides".
Biodiesel hydrocarbon chains are generally 16 to 20 carbons in length,
and they are all oxygenated at one end, making the product an excellent
fuel. As discussed below, several chemical properties of the Biodiesel
allow it to burn cleanly and actually improve the combustion of
petroleum diesel in blends.
A recent (1997) survey of recreational boaters using Biodiesel
on the San Francisco Bay confirmed these findings. Boaters buy Biodiesel
for the benefits, and clean emissions from diesel engine exhaust
is a major driving force in the marine market. From the survey results
among 100 boaters using Biodiesel at various blends over the past
3 years, 98% reported an improvement in the exhaust odor (smells
more like french fries), 91% reported a reduction in smoke, and
56% indicated a reduction in soot deposits on the transoms and decks
of their boats.
Biodiesel blends should have a beneficial impact on human health
by reducing dangerous particulates and enhancing catalyst performance
in vehicles. The National Biodiesel Board emphasizes the importance
of reductions in EPA-regulated emissions by citing a 1993 study
published in the New England Journal of Medicine which concluded
that "fine particulate air pollution, or a more complex pollution
mixture associated with fine particulate matter, contributes to
excess mortality in certain U.S. cities." More recent work (1996-1998)
confirmed that Biodiesel contributes to the reduction of heavier
(longer chains, C13+) hydrocarbons as well as reducing carcinogenic
polyaromatic hydrocarbons (PAHs).
Several emissions reduction studies have been performed by the
Southwest Research Institute (SWRI) over the past 5 years. In a
1994 study on light diesel trucks, Biodiesel in a 20% blend (B-20)
was shown to reduce particulate matter (PM) by 14% in new engines.
However, from our own from field observations with boats and test
cars, Biodiesel appears to be even more effective in reducing smoke
from the older engines typical of most recreational boats. The reduction
in PM when B-20 is used is due to a reduction in insolubles (particles),
generally composed of carbon soot. Catalytic converters (used in
trucks and cars) can further contribute to the reduction in PM when
B-20 is used.
Subsequent SWRI studies were presented at a Biodiesel Emissions
Testing Meeting in Seattle in 1996. The SWRI studies were conducted
with the most efficient diesel engine produced by Cummins for pick
up trucks: a 1995 5.9 Liter inline 6-cylinder, 4-stroke engine,
with direct injection, a turbocharger and an intercooler. The rated
horsepower of the test engine was 160 HP at 2500 rpm. Studies were
conducted with and without the stock catalytic converter supplied
with the engine (unfortunately not available for marine engines).
The engine emissions tests were conducted under transient heavy
duty loads to simulate road use.
Several types of Biodiesel were tested, including Biodiesel derived
from another oil crop, winter rapeseed. Rapeseed is grown extensively
in Idaho, Canada and Europe to produce Canola. Biodiesel made from
Canola has very similar properties to the Biodiesel made from soybean
and other plant oils. In the Idaho study, the Biodiesel test fuels
were (100%) rapeseed ethyl esters (REE), rapeseed methyl esters
(RME), 50% blends of REE or RME, and 20% blends of REE or RME with
petrodiesel. The reference fuel was conventional (Texas) No. 2 petrodiesel
("2D"), a low-sulfur diesel formulation mandated nationally by the
EPA since 1993 .
More recent work at the SWRI was presented at a Biodiesel Environmental
Workshop in Washington, D.C. (June 4, 1998) by Christopher Sharp,
the principal investigator. The newest work provides updates on
the effects of Biodiesel on diesel engine exhaust emissions and
performance.
The 1998 SWRI report summarized emission studies on three diesel
truck engines: a 1997 Cummins 14-L inline 6 cylinder engine, a 1997
Detroit Diesel 8.5-L incline 4 cylinder engine, and a 1995 Cummins
5.9-L inline 6 cyclinder engine. The test fuels were neat (100%)
Biodiesel, the B-20 blend of biodiesel with diesel and a standard
low-sulfur standard petroleum diesel fuel as a reference.
Exhaust emissions were evaluated over a heavy duty transient cycle
with hot and cold starts, with and without a catalyst in some cases.
Total hydrocarbon emissions for the Cummins engines were reduced
by 20% for the B-20 blend in the 1997 model and by 31% for the 1995
B-5.9 model. When the same engines were tested with 100% Biodiesel,
there was a 94% drop in total hydrocarbons for the 1997 engine and
a 72% drop for the 1995 engine relative to No. 2 low sulfur diesel
fuel. The Detroit Diesel engine generated less emissions in general,
with little change as the test fuel was switched to B-20, but an
82% drop when the test fuel was neat Biodiesel.
Smoke and Soot Reductions
Smoke (particulate material) and soot (unburned fuel and carbon
residues) are of increasing concern to urban air quality problems
that are causing a wide range of adverse health effects for their
citizens, especially in terms of respiratory impairment and related
illnesses. Boaters always complain of the smoke from their diesel
engines as they motor back to port. They also resent the soot accumulation
on the transoms and decks of their boats.
The lack of heavy petroleum oil residues in the vegetable oil esters
that are normally found in diesel fuel means that a boat engine
operating with Biodiesel will have less smoke, and less soot produced
from unburned fuel. Further, since the Biodiesel contains oxygen,
there is an increased efficiency of combustion even for the petroleum
fraction of the blend. The improved combustion efficiency lowers
particulate material and unburned fuel emissions especially in older
engines with direct fuel injection systems.
In the 1996 study performed by the Southwest Research Institute,
the effect of oxygen content (by percent oxygen) on the production
of particulates smoke and soot was studied using the same Cummins
diesel test engine cited above. The study established, for example,
that a B-20 blend (approximately 2% oxygen for RME-20) reduces particulate
soot by approximately 30% (from 0.06 for diesel no. 2 to 0.04 G/HP-Hr
for rapeseed methyl ester at 20%).
An earlier 1994 EPA Transient Cycle Emissions Test undertaken by
the Southwest Research Institute compared emissions from an engine
burning No. 2 low-sulfur diesel with those from an engine using
the B-20 blend in combination with an oxidation catalyst. Compared
with the low-sulfur No. 2 diesel, the B-20 blend with an oxidation
catalyst reduced particulate matter by 45%, total hydrocarbons by
65%, and carbon monoxide by 41%.
Pioneering studies performed by the Colorado Institute for Fuels
and High Altitude Engine Research used 1991 model series engines.
They reported a 13.7% drop in particulate matter and a 12.7% drop
in total hydrocarbons when using a B-20 blend.
In the updated 1998 report from the Southwest Research Institute
studies, oxygen was shown to be the driving mechanism for soot reduction
in truck engines operating on various blends of Biodiesel. The higher
the oxygen content of the Biodiesel blend, the greater the reduction
in soot emissions. However, not all the particulate emissions is
fuel related. With the Cummins B-5.9 test engine, about 22% of the
particulate emissions was unburned lubrication oil that did not
change significantly when the fuels were switched to B-20 or neat
Biodiesel. Carbon soot, in contrast, made up over 50% of the particulate
emissions and this carbon soot component was reduced by 20% with
the B-20 blend, and reduced with the neat Biodiesel by 66% in the
Cummins B5.9 engine and by 71% with the Detroit Diesel engine.
Carbon Monoxide Emissions
Carbon monoxide gas is a toxic byproduct of all hydrocarbon combustion
that is also reduced by increasing the oxygen content of the fuel.
More complete oxidation of the fuel results in more complete combustion
to carbon dioxide rather than leading to the formation of carbon
monoxide. In the 1998 report by the Southwest Research Institute
on the effects of Biodiesel on truck engine exhaust emissions, the
levels of carbon monoxide were shown to be reduced from 8% to 22%
with a B-20 blend, depending on the type of engine. When the fuel
was switched from low-sulfur petroleum diesel to neat Biodiesel,
there was a 28% to 37% drop in the carbon monoxide emissions.
Polyaromatic Hydrocarbon
Emissions
Polyaromatic hydrocarbons (PAHs) are a class of heavy oil petroleum
hydrocarbons defined by their complex ring structures and unique
qualities. They consist of multiple benzene ring structures that
make them insoluble, slow to burn and carcinogenic. PAHs are regulated
by the EPA in engine emissions. In the 1998 SWRI report, the Cummins
N-14 engine had a 12% drop in PAH emissions when operating on B-20
blend relative to petrodiesel, and a 74% drop in PAHs when the fuel
was switched to neat Biodiesel. The Detroit Diesel engine had a
29% reduction in PAHs operating on B-20 and a 68% reduction when
operating on neat Biodiesel. These data suggest major gains in improving
the air quality around diesel engines in vehicles and boats operating
on Biodiesel.
Nitrogen Oxides
The nitrogen oxides result from the oxidation of atmospheric nitrogen
at the high temperatures inside the combustion chamber of the engine,
rather than resulting from a contaminant present in the fuel. Although
nitrogen oxides (NOx) are considered a major contributor
to ozone formation, they are also a reality of operating internal
combustion engines. There are consistent reports of slight increases
(several percent) in NOx emissions with Biodiesel blends
that are attributable, in part, to the higher oxygen content of
the fuel mixture. More oxygen and better combustion of the fuel
also means more formation of NOx emissions with Biodiesel
blends.
In several research studies conducted since 1993 in the U.S. and
Europe, EPA-regulated emissions from an unmodified engine operating
on a 20% Biodiesel/80% petrodiesel blend were shown to be lower
than those for petroleum diesel, except for NOx
(nitrogen oxides) emissions, which can be 2-5% above baseline emissions.
Some reductions in NOx emissions can be attained by
retarding the timing of ignition and slowing the burn rate of the
fuel in the combustion chamber. In the EPA Transient Cycle Emissions
Test (Southwest Research Institute) study with the 1988 DDC 6V-92
engine, there was a 7% increase in NOx emissions that
accompanied the 45% reduction in particulate matter and 65% reduction
in hydrocarbons (in combination with an oxidation catalyst). Unfortunately,
any improvements in NOx emissions are usually offset
by increases in hydrocarbon, particulate material and carbon monoxide
emissions caused by the mechanical adjustments to the engine. In
the case of the Transient Cycle Emissions Test, a one-degree timing
change in the diesel engine did result in a net reduction of NOx
emissions by 2%, but at the expense of slightly less dramatic reductions
in the particulate matter (reduced by 40%), hydrocarbons (reduced
by 58%) and carbon monoxide (reduced by 34%). In Europe, the delays
in engine ignition timing have been successfully combined with the
use of catalytic converters to achieve similar reductions in both
NOx emissions and hydrocarbon emissions from transit
buses.
In the 1996 Southwest Research Institute study cited above, the
use of a catalytic converter improved the reduction of hydrocarbon
emissions with a B-20 blend of rapeseed methyl esters from 29% (without
converter) to 41% (with converter) for the Cummins test engine without
any timing delays. NOx emissions were reduced 3%.
Biodiesel
Helps Reduce Greenhouse Gases
Unlike other "clean fuels" such as compressed natural gas (CNG),
Biodiesel and other biofuels are produced from renewable agricultural
crops that assimilate carbon dioxide from the atmosphere to become
plants and vegetable oil. The carbon dioxide released this year
from burning vegetable oil Biodiesels, in effect, will be recaptured
next year by crops growing in fields to produce more vegetable oil
starting material. The U.S. is under considerable pressure from
the international community (for example, at the December 1997 Kyoto
Conference) to take seriously its efforts to reduce carbon dioxide,
carbon monoxide and other greenhouse gases released, in part, by
the combustion of fossil fuels in vehicles. While anthropogenic
(man-made) CO2 production accounts for only about 4-5%
of the net CO2 emissions, it is sufficient to have caused
a net gain over the past 100 years. Fossil fuel combustion accounts
for 70% of the total anthropogenic CO2 contribution.
Supplementing our dwindling fossil fuel reserves with biomass-based
fuels (Biodiesel, for petrodiesel; biomass-based alcohols or hydrogen
for gasoline) helps reduce the accumulation of CO2.
Positive
Energy Balance for Solar Energy in Biodiesel
Although it takes fossil energy to produce and transport biofuel,
Biodiesel has a very favorable energy balance, especially relative
to energy-negative ethanol from corn. Biodiesel production has positive
energy balance ratios ranging from 2.5:1 (Institute for Local Self-Reliance)
up to 7.4:1 in Europe, depending on oil crop and distance required
to transport the raw materials.
LOWER IMPACT ON
MARINE ENVIRONMENT
Water pollution should also be reduced by using Biodiesel in boat
engines since there will be more efficient burning of the fuel mixture,
less carbon (soot) accumulation and particulate (smoke) emissions.
Faster starting and smoother operation also should reduce the discharge
of unburned fuel. Any accidental discharges of small amounts of
Biodiesel should have relatively little impact on the environment
compared to petroleum diesel, which contains more toxic and more
water-soluble aromatics. Nonetheless, the methyl esters could still
cause harm.
Comparatively
Low Toxicity to Marine Plants and Animals
From 1994 through 1996, CytoCulture conducted a series of tests
in collaboration with the California Department of Fish & Game
(Office of Oil Spill Prevention & Response) to document the
impact of vegetable methyl esters on various native species of marsh
plants and marine organisms. Because larval forms of fish and shell
fish are much more sensitive than the adult forms, all of the marine
toxicity studies were performed with larvae of established test
species. The studies indicated that the Biodiesel, while not completely
harmless to the larvae of crustacea and fish, is much less toxic
than petroleum fuels and crude oil.
In research conducted for CytoCulture in 1994, the LC50 (concentration
required to kill 50% of the population) for larval test fish (Menidia
Beryllina) exposed to soy methyl ester Biodiesel was 578 ppm
relative to an LC50 of 27 ppm for reference fuel oil. In larval
shrimp (Mysidopsis Bahia) toxicity assays, the LC50 for the
soy methyl ester Biodiesel was 122 ppm compared to the LC50 of 2.9
ppm for the reference fuel oil.
In 1996, follow-up acute toxicity bioassays were performed by a
different laboratory on recycled cooking oil methyl esters for CytoCulture
using the same protocol and the same two test species. The recycled
cooking oil Biodiesel had an average LC50 of 736 ppm in the Menidia
fish larvae tests compared to the average LC50 of 39 ppm for the
reference fuel oil. In the Mysidopsis toxicity bioassay,
the recycled cooking oil Biodiesel had an LC50 of 124 ppm compared
to the LC50 of 5.9 for the reference fuel oil.
In subsequent gas chromatography studies on the solubility of Biodiesel
methyl esters, it was determined that much of the apparent toxicity
observed in abalone, shrimp and fish larvae was due to suffocation
or coating of exposed gills as the tiny larvae swam into dispersed
globules of the methyl esters. The concentrations for the reported
LC50’s exceed the saturation concentration for Biodiesel in
seawater, further indicating that the observed marine toxicity is
probably due to the formation of globules rather than due to a true
chemical toxicity of dissolved-phase product. In other words, the
Biodiesel methyl esters have very low solubility in water (7 ppm
in San Francisco Bay seawater) compared to petroleum diesel that
contains benzene, toluene, xylene and other more water-soluble,
highly toxic compounds. However, when the Biodiesel is vigorously
blended into water (as required by the EPA test protocols), the
methyl esters form a temporary emulsion of tiny droplets that appear
to be harmful to the swimming test larvae.
In earlier investigations of Biodiesel, aquatic toxicity studies
conducted in 1993 by CH2M Hill in Oregon indicated that rapeseed
methyl esters had an LC-50 of 23 ppm for Daphnia Magna (shrimp
larvae) relative to diesel fuel which had an LC50 of 1.43 ppm, a
15-fold difference in apparent toxicity.
Acute bioassays of bluegill adult fish conducted at the University
of Tennessee in 1996 showed that fish dosed with engine exhaust
from a 110-HP Volvo marine diesel engine experienced mean mortality
values of 25.9% and 22.1% for biodiesel and petrodiesel, respectively.
The investigators commented that the petrodiesel dispersion in the
engine’s wet exhaust tended to settle out more than the biodiesel,
and therefore might have appeared to have less impact on the fish
than the biodiesel droplets which remained suspended in the water.
However, the study also noted that the production of carbon monoxide
and soot was reduced by using Biodiesel. A major health and environmental
concern with engine exhaust is the emission of polyaromatic hydrocarbons
from burning fuel and engine oil. Polyaromatic hydrocarbons (PAHs)
found in smoke and soot are complex, multi-ring compounds that can
be carcinogenic and toxic. Water dosed with biodiesel exhaust at
a 50% engine load had non-detectable levels of polyaromatic hydrocarbons
(PAHs are complex multi-ring compounds in petroleum that can be
carcinogenic), while the exhaust from the engine operating with
petroleum diesel had anthracene and naphthalene, both carcinogenic
PAHs.
Low
Solubility and High Biodegradation Rate for Biodiesel in Bay Water
Biodiesel methyl esters are actually quite insoluble in fresh or
sea water, with a saturation concentration of 7 ppm (sea) and 14
ppm (fresh) at 17 Deg. C, whereas petroleum diesel can partition
aromatics into water in concentrations of hundreds of ppm. The dissolved
phase of the Biodiesel methyl esters was shown to breakdown by the
biodegradation action of naturally occurring bacteria present in
San Francisco Bay sea water. The half-life for the biodegradation
of the vegetable methyl esters in agitated SF Bay water was less
than 4 days at 17 Deg. C., about twice as fast as petroleum diesel
(reported by others).
In the environmental remediation field, CytoCulture developed an
oil spill cleanup solvent (CytoSol Biosolvent) based on vegetable
oil methyl esters similar to Biodiesel. The CytoSol Biosolvent
has been licensed by the California Department of Fish & Game
as a "shoreline cleaning agent" to extract crude oil from shorelines
and marshes after a spill. The acceptance of this product by the
state for application to shorelines emphasizes the low toxicity
and low water solubility of the esters. See the CytoCulture web
site for more background on the CytoSol Process cleanup technology.
Biodegradability
of Biodiesel in the Aquatic Environment
A study conducted at the University of Idaho in 1995 determined
that rapeseed Biodiesel would biodegrade about twice as fast as
petroleum diesel using a standard EPA test protocol based on carbon
dioxide evolution and gas chromatography. Further, the Biodiesel
was shown to enhance the biodegradation rate for diesel fuel in
a blend. As was also confirmed at CytoCulture, hydrocarbon-degrading
bacteria can metabolize both the Biodiesel and petroleum diesel
at the same time. Because Biodiesel is a simple, straight carbon
chain with two oxygens at one end (mono-alkyl ester), it is more
readily metabolized by bacteria that normally break down fats and
oils in the environment. The petroleum diesel hydrocarbons lack
oxygen, and represent a very complex mixture of hydrocarbons with
multiple double bonds, and many other branched, cyclic and cross
linked chains. The more complex chemical strucutures of diesel hydrocarbons
makes them more difficult to biodegrade, and in many cases, toxic.
The biodegradation rate of rapeseed biodiesel in shake flasks with
fresh water was found to be comparable to dextrose (a test sugar)
and about twice as fast as for petroleum diesel. In the Idaho study
(Peterson, Reece, et al., 1996), the rapeseed esters were degraded
by 95% at the end of 23 days where as the diesel fuel in this test
was only about 40% degraded after 23 days.
Spills
of Biodiesel Can Still Harm the Environment
For the boating environment, Biodiesel should have less impact
to aquatic and marine organisms than petroleum diesel if accidentally
spilled or inadvertently discharged over the side. However, the
US EPA still considers spills of animal fats and vegetable oils
harmful to the environment. In an October, 1997 ruling under the
Clean Water Act, as amended by the Oil Pollution Act of 1990, vegetable
oils are considered "oil" like petroleum. (In France, Biodiesel
is classified as food for transportation purposes.)
Spilling Biodiesel into the water would be as illegal as discharging
petroleum fuels overboard. Waterfowl and other birds, mammals and
fish that get coated with vegetable oils could die from hypothermia
or illness, or fall victim to predators. Even though the Biodiesel
is relatively non-toxic and less viscous than vegetable oil, it
can still have a serious impact on marine and aquatic organisms
in the event of a big spill. We recommend that the Biodiesel always
be handled like any other fuel to avoid contamination of our bays
and waterways, and that boaters obey all laws governing the handling
of engine fuels and oils.
ENGINE PERFORMANCE
Mechanical
Advantages to Using Biodiesel with Reformulated "Low Sulfur, Low
Aromatics" Diesel
Biodiesel methyl esters improve the lubrication properties ("lubricity")
of the diesel fuel blend. Long term engine wear studies have been
conducted in Europe and in the US. Porsche (Germany) determined
that neat (100%) Biodiesel reduced long term engine wear in test
diesel engines to less than half of what was observed in engines
running on current low sulfur diesel fuel. Lubricity properties
of fuel are important for reducing friction wear in engine components
normally lubricated by the fuel rather than crankcase oil.
When the California Air Resources Board (CARB) mandated stricter
laws than the Federal requirements for reformulating "low sulfur,
low aromatic" diesel fuel in 1993, the result was a decrease in
the lubricity of that fuel. The reduction in aromatics at that time
also changed the elastomeric properties of the fuel resulting in
the shrinking of gaskets, O-rings and seals in older engines. The
mechanical wear and fuel leaks caused so many problems (e.g., expensive
rebuilds of fuel pumps) that California truckers held a one day
strike in December, 1993 to protest the new fuel laws. Since then,
truckers, boaters and other operators of diesel engines have turned
to a variety of petroleum additives (in extreme cases, transmission
fluid) in an attempt to protect their engines from excessive wear
and gasket leaks associated with the new "CARB low sulfur/low aromatics"
diesel fuel.
More than 100 Biodiesel demonstrations, with over 10 million road
miles in trucks, have confirmed the performance benefits of this
fuel additive for emissions and mechanical lubricity. No adverse
durability or engine wear problems were found; in fact, in road
tests with heavy duty truck engines, engine wear was significantly
decreased after running 100,000 miles on blends of Biodiesel (University
of Idaho studies).
Lubricity Properties
Biodiesel has been studied extensively in Europe and the U.S. for
its effect on long term engine wear, particularly with respect to
those components normally lubricated by the fuel itself. Fuel pumps
and injector pumps depend on the operating fuel for lubrication
of moving parts and shaft bearings. Initial work on the lubricity
of Biodiesel, performed by Mark-IV Group and the Southwest Research
Institute in 1994, established a clear advantage to blending Biodiesel
with petrodiesel to achieve superior lubrication.
Lubricity properties are measured at the Southwest Research Institute
(SWRI) by a "Ball On Cylinder Lubricity Evaluator" (BOCLE) machine
to measure metal to metal hydrodynamic wear simulating rotating
shafts and bearings. A static steel ball is loaded onto the edge
of a rotating disc and the diameter of the subsequent scar on the
ball is measured (similar reciprocating machines exist in Europe
to measure scar on a steel ball, and newer versions have been developed
in America to improve lubricity measurements). The BOCLE test does
not measure adhesive friction wear.
Tests run by Exxon showed that, compared to reference diesel fuel
in 1993, a 20% blend of Biodiesel had significant, quantifiable
improvements in reducing wear (193 micron scar for B-20 vs. 492
micron scar for petrodiesel) and friction (0.13 micron scar for
B-20 vs. 0.24 micron for petrodiesel) while improving film coating
ability of the blend (93% film with the B-20 vs. 32% film with the
petrodiesel). The B-20 blend compared favorably for lubricity results
against Exxon’s own lubricity additive.
The SWRI results for the BOCLE tests confirmed the earlier Exxon
study results. Low sulfur, low aromatic ("CARB") diesel was compared
to various blends of Biodiesel (soy methyl esters). Data were presented
in values of grams of weight added to the apparatus before failure
of the fuel to adequately lubricate the metal. The higher the weight
the ball could support, the better the lubricity of the fuel. Neat
petrodiesel (low aromatic CARB) had a BOCLE result of 3,500 grams,
whereas the neat Biodiesel had a BOCLE result almost twice as high
at 6,100 grams. The B-20 blend had a BOCLE result of 4,100 grams,
close to the value for pre-1993 (high sulfur, high aromatic) petrodiesel
fuel. In concentrations below 5%, the Biodiesel had no measurable
effect on the lubricity of petrodiesel.
Follow up BOCLE studies at SWRI in 1996 concluded that Biodiesel
methyl esters had even better lubricity properties than previously
reported. The Biodiesel (RME) had a BOCLE value of 7,000 grams vs.
4,250 for low sulfur diesel (not CARB diesel), and the B-20 blend
had a BOCLE value of 4,600 grams. Scar wear diameters were also
encouraging, with a 405 micron scar reported for petrodiesel vs.
a 190 micron friction scar for the B-20 blend.
Subsequent field studies on light duty truck engines (5.9L Cummins
diesel at the University of Idaho) have corroborated these results
by finding an "absence of wear" and friction scars on engines broken
down for inspection after a 100,000 mile road test running on 28%
Biodiesel. In a University of Idaho durability test (1,000 hour
tests on small diesel engines), it was found that methyl ester Biodiesel
was equivalent to no. 2 diesel on the basis of long term engine
performance and wear. The primary factors evaluated in that study
were engine brake power and torque, injector tip coking (carbon
deposition), and engine component wear based on oil analysis.
In house monitoring over the past 5 years of our "Biofuel Test
Vehicles" (a Mercedes Benz 300TD diesel station wagon and a 1985
BMW 524-Diesel) at CytoCulture has shown no evidence of unusual
wear or polymerization of engine crankcase oil (analysis performed
by Herguth Laboratories, Vallejo, CA) after more than 40,000 miles
of operation on 30-100% blends with Biodiesel.
Heat of Combustion Properties
Relative to petroleum diesel no. 2, Biodiesel has a slightly lower
heat of combustion on account of its oxygen content (petroleum diesel
hydrocarbons are not oxygenated). The heat of combustion for soy
methyl esters is 128,000 BTU (British Thermal Units) per gallon
vs. 130,500 BTU/gal. for petrodiesel. In the Southwest Research
Institute study (1996), the heat of combustion for rapeseed biodiesel
in blends were compared with petrodiesel. Petrodiesel had 18,400
BTU/lb., neat biodiesel had 16,200 BTU/lb. (88%) and a 20% blend
of rapeseed methyl ester biodiesel had 17,900 BTU/lb. (97%). However,
with the added oxygen, the net combustion efficiency for the blended
fuel is increased, which should compensate for the slight drop in
BTU content. The differences would be most noticed at low rpm and
high engine load when the engine would most benefit from more oxygen.
Power Differences
Studies conducted in the U.S. and Europe generally indicate that
blends of Biodiesel and petrodiesel result in small decreases in
overall power output of engines. Only two studies have been conducted
with marine engines, one by a German scientist (Dr. Claus
Breuer) at the Technical University in Hannover (Ph.D. thesis in
1994) and the other by Alvin Womac’s group at the Department
of Agricultural Engineering at the University of Tennessee. The
German study involved a Deutz 4 cylinder marine diesel engine (direct
injection) found on fishing boats in Europe and the Tennessee study
evaluated a 110 HP Volvo marine diesel engine, also used in work
boats and fishing boats. Volvo also makes smaller single and double
cylinder diesel engines for recreational sailboats.
The German study confirmed similar results obtained by Mercedes
Benz showing that the maximal torque curve for an engine under load
remains essentially unchanged for rapeseed methyl esters relative
to pure petrodiesel. Despite the lower volumetric heating value
and the consequent lower maximum power output of Biodiesel, the
practical results are roughly the same. At a 20% blend, there would
probably be no noticeable difference in power output. Good performance
in fuel combustion with Biodiesel and its blends resulted in a smooth
running engine.
In the Volvo marine diesel engine study in Tennessee (110-HP, 2.39
L, 4-cylinder, direct injection engine), a tractor dynamometer was
used to measure power outputs under selected loads through an engine-mounted
reverse drive gear. Exhaust emissions were also tested along with
fuel consumption tests under various loads. The conclusions of these
tests were that power produced from 100% soy methyl ester Biodiesel
was from 2 to 7 percent less than produced from petrodiesel, depending
on the load-speed point. However, at or near maximum throttle (3,800
rpm), the two fuels performed the same. Interestingly, at the lowest
engine speed (1855 rpm) at full throttle under heavier load, there
was a 13% increase in power with Biodiesel as compared to
petrodiesel.
The Tennessee study indicated that using 100% Biodiesel in marine
direct-injection diesel engines, with design and construction similar
to the Volvo test engine, could be recommended without any significant,
noticeable differences in operation, power performance and fuel
usage.
In the 1998 study at the Southwest Research Institute on Biodiesel
effects on diesel engine performance, engine power in the 1997 Cummings
truck engine operating on the B-20 blend was at 98.5% of the power
attained with low sulfur No. 2 diesel. At 100% Biodiesel, the engine
generated 92% of the power. For a Detroit Diesel truck engine (1997),
the power was 98% with the B-20 and 92% with the neat Biodiesel.
Fuel Consumption Differences
Biodiesels are mono-alkyl esters containing approximately 10% oxygen
by weight. The oxygen improves the efficiency of combustion, but
it takes up space in the blend and therefore slightly increases
the apparent fuel consumption rate observed while operating an engine
with Biodiesel. In the Southwest Research Institute study (1996),
the fuel consumption was found to increase by only 2% for a B-20
blend with methyl esters, and by 14% when methyl ester Biodiesel
was used at 100% in the Cummins test engine operated under transient
heavy loads. The brake-specific fuel consumption was 0.43 lb./HP-Hr
for regular petrodiesel no. 2, 0.44 lb./HP-Hr for the B-20 blend,
and was 0.50 lb./HP-Hr for the neat RME Biodiesel.
In testing Biodiesel in the CytoCulture Mercedes Benz diesel station
wagon over the past 4 years, there was about a 15% net decline in
the mileage obtained using neat Biodiesel vs. petrodiesel. No change
in power, acceleration or engine temperature was observed, but the
engine was quieter and smoother at idle when fueled with Biodiesel.
At a 20% blend with petroleum diesel, the fuel consumption differences
are practically unnoticeable.
These local observations were confirmed by the 1998 engine performance
studies at the Southwest Research Institute. Fuel consumption in
a 1995 Cummings B-5.9 truck engine increased by 9% with the B-20
blend, and by 18% with the neat Biodiesel. Better fuel economy was
noted for a 1997 Cummings N-14 truck engine with a 3% drop
in fuel consumption using B-20 and a 13% increase with the neat
Biodiesel.
Engine Seals, Gaskets
and Hoses
The oxygenated methyl esters of vegetable oil cause Biodiesel to
have surprisingly strong solvent properties with respect to natural
rubber and several soft plastics. As a result, old rubber fuel lines
and some seals or gaskets on fuel tanks may slowly deteriorate in
the presence of higher concentrations of Biodiesel. Fortunately,
few of these solvent effects are noticed at a B-20 blend, and most
of the problems associated with the solvent effects occurred with
boats using 100% neat Biodiesel. When fuel lines or gaskets are
affected, they usually get sticky over time and soften or swell,
causing fuel to drip from connections. In one case, the rubber fuel
line between the primary filter and the fuel pump on a Yanmar sailboat
engine became tacky, but did not leak, after 4 years of operating
on 100% Biodiesel. The best solution is to replace affected lines
and gaskets with modern synthetic hoses and seals.
Conventional US Coast Guard approved fuel lines are resistant to
Biodiesel (neat) and proven in sailboat testing over the past 3
years. In California, an approved fuel hose readily available in
marine stores is:
"Trident Barrier Fuel Hose, USCG Approved Type A-1, SAE J1527 (2/93)"
In bench top studies conducted at CytoCulture, the Trident hose
proved to be resistant to neat Biodiesel over a period of months,
although the hose did absorb Biodiesel and swell slightly (tightens
under hose clamps). With 20% blends, there have been no reports
of any problems with these new fuel hoses. Even at 100% Biodiesel,
we have observed only minor swelling on the Trident Barrier fuel
hoses used on test engines operating on neat Biodiesel for several
years.
Studies conducted for the National Biodiesel Board on the materials
compatibility of Biodiesel concluded that the only hose and gasket
material that was truly resistant to the solvent effects of methyl
esters was Viton. Viton fuel hoses (Goodyear) can be special ordered
for boats (usually expensive at over $5.00/ft for 5/16" line), but
we know of only one boat in the San Francisco area that converted
to Viton fuel lines as a precaution.
In CytoCulture’s 1997 survey of 100 boaters using Biodiesel
in the San Francisco Bay area, 2% of the respondents had trouble
with drips caused by swelling gaskets and seals, usually at the
fuel filter. Again, replacing these gaskets with modern synthetic
materials appeared to solve the problem. Raycor filters, for example,
have functioned normally with 100% Biodiesel and have had no gasket
problems in engines operated with neat Biodiesel over the past 4
years. (The 1997 boater survey is on the CytoCulture web site).
In the survey, 5% of the boaters reported minor problems with the
Biodiesel if they spilled it on decks, on their engine or into their
bilges. The solvent properties of the esters in Biodiesel can loosen
old paint on engines or on painted surfaces in the bilge. Besides
staining raw wood surfaces, the Biodiesel is particularly harmful
to teak decks with polysulfide seams (use extra caution when filling
tanks via deck ports). The Biodiesel could also harm rubber engine
mounts if it were spilled and not cleaned up immediately. Use paper
towels or absorbant pads to remove spilled Biodiesel and then clean
the surfaces thoroughly with warm soapy water.
Warranties
and Engine Manufacturer Endorsements
Marine diesel engine manufacturers in United States, Europe and
Japan have all recognized the growing role of Biodiesel as a viable
fuel additive, and in most cases, as a complete alternative fuel
(100%). Two of the sponsors of the SUNRIDER expedition of 1992-1994
were the marine diesel engine manufacturers: Mercruiser (inboard/outboard
diesel engine) and Yanmar (outboard diesel engines), endorsing Biodiesel
as a suitable alternative fuel to power Bryan Peterson’s 28-ft
inflatable Zodiac boat around the world. This 35,000 mile adventure
remains the most famous and most publicized demonstration of using
Biodiesel in marine engines. Over 18,000 gallons of donated soy
methyl ester Biodiesel was provided to SUNRIDER at various destination
ports and rendezvous locations (including a mid-ocean fuel transfer
from a ship). Bryan started out from Pier 39 in San Francisco in
1992 and returned under the Golden Gate bridge on September 8, 1994,
powered by 100% soybean Biodiesel. Brian’s last 100 gallons
of Biodiesel were donated by CytoCulture when he stopped in Santa
Cruz on the final leg up the coast of California. At that point,
he remarked, "The Biodiesel works….No problems."
Engine manufacturers in Europe have a long history of supporting
the Biodiesel movement, and those that produce marine engines continue
to endorse the alternative fuel use in their equipment. Some manufacturers
warranty their marine engines for use with 100% Biodiesel for late
models or for older engines retrofitted with newer synthetic hoses
and gaskets that proved more resistant to the pure methyl esters
over extended periods of time. Some prefer to warranty Biodiesel
engines on a case by case basis. In the U.S., diesel engine manufacturers
generally stand by their warranties as long as the fuel used in
their engines meet the ASTM D-975 standards defining fuel for compression
ignition engines. All of the B-20 blends of Biodiesel produced in
America meet the ASTM D-975 specifications. Contact your engine
manufacturer for updates on their acceptance of B-20 blend as an
acceptable fuel within the scope of their warranties.
SAFETY
AND AESTHETIC ADVANTAGES OF BIODIESEL
Boaters can appreciate the user friendliness of handling Biodiesel
in their boats. The product has no noxious odors and is considered
as harmless to handle as salad oil, but we always encourage safety
precautions to avoid splashing it in your eyes, on your clothes,
on your boat or into the water. The product smells and feels like
cooking oil. In an early study sponsored by the National Biodiesel
Board (1993), the product had less toxicity in animal testing than
table salt (grams per kg body weight).
No Noxious or Carcinogenic
Fumes
Biodiesel vegetable oil methyl esters contain no volatile organic
compounds that would give rise to any poisonous or noxious fumes.
The Biodiesel does not contain any aromatic hydrocarbons (benzene,
toluene, xylene) or chlorinated hydrocarbons. There is no lead or
sulfur to react and release harmful or corrosive gases. However,
in blends with petrodiesel there will continue to be significant
fumes released by the benzene and other aromatics present in the
petroleum fraction (80%) of the blend.
No Risk of Explosion
from Vapors
Since the Biodiesel has no volatile components (vapor pressure
of less than 1 mm Hg) and a high flash point (typically over 360
Deg. F), the product poses no risk of explosion caused by fumes
accumulated below deck. The only significant fire risk would be
from the spontaneous combustion of rags and paper towels soaked
in Biodiesel and stored in an area with low ventilation, or high
temperatures (like the inside of an engine room).
STORAGE CONDITIONS
FOR BIODIESEL
Biodiesel can be stored for long periods of time in closed containers
with little head space. The containers should be protected from
weather, direct sunlight and low temperatures. Avoid long term storage
in partially filled containers, particularly in damp locations like
dock boxes. Condensation in the container can contribute to the
long term deterioration of the petroleum diesel or biodiesel (see
below). Low temperatures can cause the Biodiesel to gel, but the
Biodiesel will quickly liquefy again as it warms up. In cold weather
(near or below freezing), additives can be used to prevent gelation
(fuel additives for diesel fuel used in cold weather are available
from Exxon, Hammond, and other manufacturers).
Fuel tanks should be kept as filled as possible (regardless of
whether they contain Biodiesel), particularly during rainy winter
months or periods of inactivity, to minimize the condensation of
moisture. Condensed moisture accumulates as water in the bottom
of your tank and can contribute to the corrosion of metal fuel tanks,
especially with petroleum diesel that also contains sulfur. The
condensed water in the fuel tank can also support the growth of
bacteria and mold that use the diesel and Biodiesel hydrocarbons
as a food source. These hydrocarbon-degrading bacteria and molds
will grow as a film or slime in the tank and accumulate as sediment
over long periods of time. These hydrocarbon-degrading microbes
are frequently referred to incorrectly as "algae" in advertisements
for fuel treatments, perhaps because the colonies often have a reddish
orange color and tend to form mats.
Petroleum diesel and Biodiesel are both susceptible to growing
microbes when water is present in the fuel, but the solvent action
of the Biodiesel can also cause microbial slime to detach from the
inside of the tank. The accumulation of the newly released slime
and sediment can be very dangerous if it clogs the fuel filters
and causes the engine to suddenly stop. It is very important to
monitor the filters on a diesel engine that has been switched over
to Biodiesel, particularly if the tank is old and has not been cleaned.
Biocides are available at marine stores to treat diesel fuels suspected
of having microbial growth. The biocides are chemicals that kill
bacteria and molds growing in fuel tanks without interfering with
the combustion of the fuel or the operation of the engine. Used
in very dilute concentrations, the biocides can inhibit the growth
of microbes over long periods of time. These products are very toxic
and should be used only as directed by the manufacturers. Precautions
should be taken to avoid any contact with the products (wear gloves
and eye protection) and to prevent any spills or drips. It is important
to remember that the biocides may kill the microbes, but they do
not remove the accumulated sediment, so expect to replace fuel filters
often as the debris is drawn from the tank. In some cases, it may
be necessary to have the fuel filtered and the fuel tank cleaned
by a professional fuel filtering service.
The microbial slime and sediment problem seems to worsen for boats
that are used infrequently since the inactivity allows the microbes
to accumulate in stable colonies. When the boat is used again, the
slime and sediment can break loose and accumulate in the fuel filters.
Accumulated sediment in fuel filters can then interrupt the flow
of fuel and shut down the engine, potentially with disastrous consequences.
In recent years, several sailboats have washed up on beaches on
account of clogged fuel filters with ordinary petroleum diesel caused
by the sudden agitation of tank sediments when the boat encountered
rough seas off shore.
As mentioned earlier, the addition of Biodiesel to a dirty fuel
tank can accelerate the release of accumulated slime. When the boat
is then used after sitting idle for a long period of time, the newly
suspended sediment can accumulate and potentially clog the fuel
filters. We urge all boaters to check their fuel filters often and
be prepared to change them after they introduce Biodiesel to an
older
fuel tank that may have accumulated slime and sediment.
More
Information on Biodiesel
Biodiesel Producers
in America
Biodiesel (vegetable oil methyl esters) are produced in the United
States as a feedstock for other consumer products (e.g., Dawn detergent),
or as an end product biofuel or solvent. These products meet the
draft specifications developed by the National Biodiesel Board,
and they meet most or all of the European specifications for Biodiesel.
These specifications assume the Biodiesel is used neat (100%) as
an alternative fuel. At least 7 producers are currently supplying
the American market with marine biodiesel from soybean methyl esters
or recycled cooking oil methyl esters.
Producers using only virgin soybean oil to make Biodiesel include:
Ag Environmental Products (AEP): "SoyGold"
9804 Pflumm Road, Lenexa, KS 66215
Tel. 800-599-9209 Fax 913-599-2121 Web site: www.soygold.com
SoyGold may be purchased from several fuel docks in Southern California.
Check the SoyGold web site for fuel dock locations.
Producers or distributors selling Biodiesel made from virgin
soybean oil and/or recycled cooking oil:
Columbus Foods, Inc.: "Biodiesel"
800 North Albany, Chicago, IL 60622
Tel. 800-322-6457 Fax 773-265-6985
Web site: www.columbusfoods.com
NOPEC Corporation: "BioBooster"
1316 G. Jenkins Blvd., Lakeland, FL 33815
Tel. 888-296-6732 Fax 941-683-1058 Web site: www.nopec.com
World Energy Alternatives (former Twin Rivers Technologies)
1 Broadway Suite 600, Cambridge, MA 02142
Tel. 617-621-1522 Fax 617-621-1523 Web site: www.worldenergy.net
Producers using recycled cooking oil exclusively to make Biodiesel:
Pacific Biodiesel, Inc.: "Biodiesel"
285 Hukilike Street, B-103, Kahului, Maui, HI 96732
Tel. 808-871-6624 Fax 808-871-5631 Web site: www.biodiesel.com
Griffin Industries / PMC Marketing Group: "Bio G-3000"
4221 Alexandria Pike, Cold Spring, KY 41076-1897
Tel. 703-256-4497 Fax 703-256-8585 Web site: www.griffinind.com
CytoCulture is a regional distributor of marine biodiesels
from recycled cooking oil and a contract supplier of B-20 for fleets.
Double
Environmental Benefit with Biodiesel from
Recycled Cooking Oil
The newer Biodiesel products (introduced in 1996-1997) produced
from recycled cooking oil offer a "double environmental benefit"
in being both renewable and recycled bioenergy products.
Waste cooking oil collected from restaurants (e.g., fryer oil for
fast foods, french fries, Chinese food, donuts, etc.) can be processed
into Biodiesel methyl esters suitable for use as a fuel additive.
In terms of performance, handling and marine toxicity, these products
are virtually identical to the Biodiesel methyl esters produced
from virgin soy bean oil in the U.S. The recycled products do have
a darker, amber color (oxidized carotene pigments), but the trace
pigment concentrations have never been associated with any engine
performance or toxicity effects.
In Europe, extensive testing of Biodiesel produced from recycled
cooking oils has confirmed that their engine performance and exhaust
emission properties are nearly identical to those of methyl esters
produced from virgin vegetable (rapeseed) oil. The Europeans have
built several new transesterification plants recently to meet the
increasing demand for Biodiesel by processing waste cooking oil
into methyl ester fuel.
All four of the American recycled vegetable oil methyl ester products
meet all specifications for American Society for Testing and Materials
(ASTM) provisional standards for Biodiesel. All four recycled products
were also shown to pass most European Union and German (final draft)
specifications for Biodiesel. All of these test protocols are predicated
on using the Biodiesel as a neat (100%) alternative fuel, rather
than as blends with petrodiesel.
In B-20 blends (20% Biodiesel / 80% CARB diesel), Biodiesel derived
from both virgin soybean oil and recycled cooking oil meet ASTM
D-975 standards defining "diesel fuel" used in compression ignition
engines (See ASTM D-975 test results in appendix). The State of
California uses the ASTM D-975 standard to enforce statutory laws
(CA Department of Food & Agriculture, Division of Measurements)
defining what is sold as fuel for diesel engines in California.
Neat Biodiesel (100%) does not qualify as a diesel fuel in
California on account of the product’s increased viscosity,
and the fact that the product is not volatile (carbon residue tests
and distillation curve data fail specifications). ASTM D-975 studies
conducted with Herguth Laboratories in California indicated that
neither the recycled cooking oil Biodiesel (NOPEC) nor virgin soybean
oil Biodiesel (SoyGold from a SF fuel dock) could meet the
ASTM D-975 specifications of a satisfactory diesel fuel. However,
the B-20 blends met all D-975 specifications.
From an environmental resource conservation point of view, building
small regional plants to produce Biodiesel from recycled cooking
oil offers a tremendous advantage in energy and resource savings.
The ideal scenario for producing an alternative fuel or additive
would be to have a local plant process local waste oil for use in
a local market. This scenario is already a reality in Florida and
Hawaii, and will soon be repeated in other regions of the country
where the combination of local market demand (e.g., boaters, government
vehicles, etc.) and abundant feedstock (used cooking oil) allow
the concept to make good economic sense.
In Idaho, at an enormous french fry processing plant, semi-tractor
trucks haul potatoes and frozen french fries hundreds of miles using
a blend of petrodiesel and Biodiesel made from recycled fry oil
at the plant in collaboration with the University of Idaho.
An obvious and important advantage of employing a local plant to
produce Biodiesel from local, low cost feedstocks for local market
consumption is lower cost. The recycled cooking oil
Biodiesels are already sold locally at prices significantly lower
than the Biodiesel products made from virgin soybean oil in the
Midwest (or distributed on the East coast). Presumably, smaller
plants could be built in other areas of the country like California
to produce methyl esters with lower transportation and feedstock
costs, thereby helping to boost the market share for Biodiesel among
boaters and other potential users.
The recent success of the "Veggie Van" is a prime example of how
even a mobile transesterification plant can generate adequate quality
Biodiesel on the road. In 1997-1998, Josh and Kaia Tickell crossed
the country with their Biodiesel-powered "Veggie Van" processing
used cooking oil into fuel by towing a small trailer-mounted system
they built themselves. See their web site (www.veggievan.org) and
read their book to learn more about their experience with Biodiesel:
From the Fryer to the Fuel Tank: How to Make Cheap, Clean Fuel
From Free Vegetable Oil. CytoCulture provided the Veggie Van
with Biodiesel during their stay in California in the summer of
1998.
Biodiesel
as a "Mainstream" Alternative Fuel
Global resources of vegetable oils and fats amount to some 62 million
tons per year, which is small compared to the annual global petroleum
consumption of 3,300 million metric tons (1995). Available vegetable
oil resources could cover less than 2% of the present petroleum
consumption, but it already has displaced 5% of the petroleum diesel
consumed in France. In Germany last year, Biodiesel use was increasing
faster than the plants could produce it, but even then, with virgin
as well as recycled feedstocks, the maximum production of Biodiesel
based on current agricultural practices could replace only about
6% of the total petroleum diesel used today. Tourist boats on lakes
in Germany and Austria routinely run on Biodiesel. On the Bodensee
(Lake Constance) that serves as a drinking water reservoir, some
vessels have been operating on neat (100%) Biodiesel for over 3
years.
The intent of all Biodiesel programs is not to replace petroleum
entirely as a fuel, of course, but to displace it in key applications
where the environmental impacts of diesel fuel are most threatening
and can be easily muted by replacing the fuel with Biodiesel or
a blend of Biodiesel. Recreational sailboats are a prime target
for using Biodiesel since they operate in Bays, estuaries, lakes
and rivers, and sailors tend to be very sensitive to the aesthetic
and environmental concerns of operating engines. Furthermore, since
sailboaters use relatively low volumes of fuel per year, the high
cost of Biodiesel is less inhibiting than it would be for power
boat and ferry operators or commercial fishermen.
As state and Federal laws evolve over the next few years to accommodate
Biodiesel as an approved alternative diesel fuel (with full fledged
ASTM specifications), more plants will be constructed to process
Biodiesel from recycled cooking oils in more coastal areas of the
country (e.g., California). Lower production costs (local feedstock,
local market) will help lower the price of Biodiesel and increase
its use in boats and vehicles.
As a result of recent legislation (fall, 1998), the US EPA and
the Department of Energy now designate the B-20 (20% Biodiesel)
blend as an official "alternative fuel" in the Alternative Fuel
Transportation Program regulations. The legislation allows government
fleets to earn equivalent "credits" for using the Biodiesel blend
in conventional diesel-powered vehicles instead of having to buy
more expensive, specialized "multi-fuel vehicles" to remain in compliance
with the Energy Policy Act. The new policy is being drafted and
should be published in the Federal Register by late spring, 1999.
The new legislation was passed after recognition that "there is
a developing market for biodiesel fuels with fuel producers prepared
to meet the needs of this market". The Senate legislation, S.1141,
will allow Biodiesel to compete on the same playing field as other
alternative fuels and will expand clean-air options for city fleet
managers, as well as encourage opportunities for boaters, farmers
and other prospective users without additional government spending,
federal mandates or subsidies. This legislation has led government
fleets in California to consider buying conventional diesel-powered
transit buses and work vehicles to operate on the B-20 blend and
receive their Energy Policy Act "fuel for credit" in lieu of buying
the multi-fuel vehicles. The capital expenditure and vehicle maintenance
savings will more than offset the $0.60-$0.70 per gallon increase
for the B-20 blend relative to the regular petroleum diesel.
CytoCulture recently received the first contract to provide the
B-20 Biodiesel blend to a government fleet in California at the
Davis campus of the University of California. This is the first
fleet in California and the first University fleet in America
to convert entirely to operating on the B-20 blend of Biodiesel.
As more fleet opportunities develop for the sale of the B-20 blend,
and Biodiesel becomes more of a mainstream alternative fuel, there
should be greater incentive to construct transesterification plants
on the west coast to convert local recycled cooking oil into Biodiesel
for local markets and at lower costs.
In another development favoring Biodiesel use in California, the
state senate is working this spring on the passage of legislation
to exempt Biodiesel blends (B-20) from state excise fuel tax. The
fuel tax on diesel fuel ($0.18 per gallon) is now applied to the
entire volume of a B-20 blend sold as a blend. As a result, consumers
and fleets end up paying 18 cents a gallon fuel tax in addition
to sales tax (7.25-8.25%) on the Biodiesel portion of the B-20 blend.
Under the proposed legislation of Assembly Bill 448, both Biodiesel
and "A-55" (proprietary diesel-water blend) would qualify as alternative
fuels and would be exempt from state diesel fuel tax for a period
of two years. After two years, the alternative fuels would be taxed
only 6 cents/gallon (1/3 of the normal 18-cent fuel tax). Eliminating,
then at least reducing the state excise fuel tax will provide a
strong "positive driver" for the Biodiesel market.
Meanwhile, the marine Biodiesel market in California remains the
first (1993) and one of the few continuous commercial markets for
Biodiesel in the United States. Over 7,000 gallons of Biodiesel
have been sold to boaters in California by CytoCulture alone.
Pricing and Availability
Marine Biodiesel retails in California for $4.95 a gallon at fuel
docks and marine supply stores where it is available. AEP sells
their SoyGold product at several fuel docks in Southern California.
CytoCulture has been distributing marine Biodiesel in Northern California
since 1994 in 5-gallon containers (state approved, recyclable plastic
containers). In 1997, CytoCulture set up 12 fuel docks and marine
supply stores from Benicia to Monterey to promote the retail distribution
of Biodiesel to boaters. CytoCulture is currently working to set
up broader distribution of Biodiesel in returnable 5-gallon
containers that would be purchased by the boater, then exchanged
for a new container every time the customer bought another 5 gallons
of the additive.
As of April, 1999, Biodiesel can also be purchased and shipped
from several of the producers listed on pages 26-27 in containers
or by the 55-gallon drum. Marine Biodiesel is no longer retailed
at fuel docks on the Chesapeake Bay, but CytoCulture and others
are working to re-establish distribution through marine supply stores.
Check the CytoCulture or NBB web sites for updates.
Learning More
About Marine Biodiesel
The National Biodiesel Board can provide more general information
on Biodiesel, including marine applications, by contacting
them at:
National Biodiesel Board
P.O. Box 104898
Jefferson City, MO 65110-4898
Tel. 800-841-5849 Fax 573-635-7913
NBB Web Site: www.biodiesel.org
For a fun and extensive review of Biodiesel activities around the
country and around the world, see Josh Tickell’s Veggie Van
site at www.veggievan.org.
From this site, you can order his book on making Biodiesel, get
updated newsletters on Biodiesel and link up to other Biodiesel
web sites around the world.
CytoCulture may be contacted for information or questions regarding
Marine Biodiesel programs in California, the results of our survey
on biodiesel use in 100 recreational boats, Biodiesel specifications
and testing protocols (European and American), California state
laws that impact Biodiesel, and upcoming activities with the Marine
Biodiesel League. CytoCulture is best reached via by telephone at
510-233-6660 or by email at: Biodiesel@cytoculture.com.
"Survey of 100 Recreational Boaters Using Biodiesel, 1994-1997"
can be downloaded as a Word file along with this Handbook from the
CytoCulture web site at: www.cytoculture.com
Questions, comments and suggestions regarding this Handbook are
always welcome. This is the second edition (April 1999) of the original
version drafted in September 1997 and printed April 1998.
Acknowledgments
This report stems from over 5 years of experience testing and promoting
the use of Biodiesel in recreational boats on the San Francisco
Bay.
The National Renewable Energy Laboratory (NREL, Golden, CO) sponsored
the study and report under a subcontract (No. ACG-7-16688-01) supported
by the U.S. Department of Energy. We would like to thank John Sheehan
and Shaine Tyson (NREL) for their role in funding and overseeing
the "Marine Biodiesel and Education Project for San Francisco Bay
and Northern California".
Special thanks are graciously extended to the following researchers
and friends who patiently helped to edit and updated this revised
edition of the Handbook:
Ryan Werner, Esq. (Emeryville, CA and Biodiesel boater)
Daryl Reese, M.S. (Utah State Univ., Pacific Biodiesel)
Alan Weber (Weber Consulting and National Biodiesel Bd)
Steve Howell (Marc IV Inc. and National Biodiesel Bd)
Chris Sharp, Ph.D. (Southwest Research Institute, TX)
Henning von Wedel, M.S. (Diesel engineer, Germany)
Joshua Tickell (Veggie Van & Institute Renewable Energy)
Bernard Wormgoor (Nauticus Surveyors) – Boater
Hans Anderson (Corinthian Yacht Club Dock Master)
Rita Gardner (Richmond Yacht Club) – Sailor/writer
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Visit the official Web site of the National
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