FAQ

Can I use biodiesel in my vehicle?

Although different manufacturers warranty different blends of biodiesel, (% of biodiesel to petroleum diesel check your warranty) Biodiesel is suitable for ALL diesel engines.

Click on the tabs below to find out more in depth answers to specific areas relating to biodiesel.

GET THE FACTS ABOUT BIODIESEL

(Info courtesy of Alberta Biodiesel Association)

Environment

Biodegradability

USDA sponsored tests confirmed biodiesel to be biodegradable since it decomposes virtually at the same rate as dextrose (a test sugar).
Compared to petroleum diesel, biodiesel degrades about four times faster, or up to 90% after approximately 1 month in contact with water.  Also, diesel blends tend to accelerate petroleum diesel biodegradability (eg: a B20 product degrades twice as quickly as pure No. 2 petroleum diesel).

Emission

Although values may vary slightly (depending on type of feedstock used), various government sponsored studies have determined that the following represent typical ‘average’ biodiesel emissions compared to conventional petrodiesel discharge:

	B5	B20	B100
CARBON MONOXIDE (CO) (poisonous gas; causes smog)	-3%	-15%	-45%
CARBON DIOXIDE (CO2) (greenhouse gas)	N/A	-15%	-80%
HYDROCARBONS (Unburned) (contributes to smog formation)	-3%	-20%	-85%
OZONE (smog; formed from hydrocarbons)	N/A	N/A	-50%
PARTICULATE MATTER (contributes to respiratory problems)	-3%	-20%	-65%
SOOT (black smoke; contributes to cancerous growth)	N/A	N/A	-85%
PAH (Polycyclic Aromatic Hydrocarbons) (carcinogenic; caused by incomplete combustion)	N/A	-15%	-80%
nPAH (nitrated Polycyclic Aromatic Hydrocarbons) (potential carcinogenic and mutagenic health issues	N/A	-50%	-90%
SULFUR OXIDES (acid rain component; pungent smell and corrosive issues)	-5%	-20%	-100%
NITROUS OXIDES (acid rain component; difficult breathing and corrosive issues)	(*)	(*)	(*)

‘N/A’ indicates that data ‘not available’
(*) Existing information showing higher biodiesel NOx emission is based on global data for feedstock grown with high nitrogen content fertilizer, and using a single test engine (early 1990’s).  Recent comprehensive tests on B20 blends by the National Renewable Energy Laboratory (U.S.) indicate NOx neutral conditions compared to petrodiesel.
NOTE:  Average combined pollution reduction using B100 amounts to about 75%  

Pollution

The Canadian Vehicle Manufacturers’ Association (CVMA), the Association of International Automobile Manufacturers of Canada (AIAMC), and the Government of Canada have all conceded that alternative fuels such as biodiesel (as well as ethanol and hydrogen) can achieve lower levels of pollution and Greenhouse Gas emissions than currently used fuels, such as gasoline and petrodiesel.
Typically, petrodiesel produces about 2.8 kg/litre CO2 (carbon dioxide) equivalent direct tail pipe emission (or about 4.0 kg/litre including upstream activities).  Comparatively, biodiesel has been estimated to reduce direct global CO2 equivalent emission by nearly 80% to about 0.6 kg/litre.
In addition, using Canadian grown canola for biodiesel, a further reduction to about 0.5 kg of direct CO2 equivalent emission has been projected, related to conservation tillage (ie: reduced CO2 emission to atmosphere), development of herbicide resistant grains, and substantial rain fed irrigation.
With respect to published data indicating 8% - 10% increased nitrogen and nitrous oxide emissions from biodiesel combustion (compared to petrodiesel), consideration must be given to the fact that such evaluations are based on average data collected from global agricultural biodiesel feedstock productions (which are normally grown using much higher nitrogen content fertilizer than Canadian grown agricultural feedstock).
Biodiesel use has the greatest variance on pollution reduction in diesel engines fitted with a mechanical fuel injection system. Also, as confirmed in the U.S. EPA Draft Report EPA-420-P-02-001 (October 2002), and in the National Renewable Energy Laboratory �Milestone Report� NREL/MP-540-40554 (October 2006), biodiesel, compared to petrodiesel, has generally a neutral effect on NOx emissions, especially for electronic fuel injected engines.
A related NOx emission finding was also mentioned in Report No. 47 (March 2006) by the ‘Francisco Josephinum Wiesenburg’ Institute, the educational and research division of the Austrian Agricultural Ministry.  It determined a direct relationship between feedstock iodine values and NOx emissions.  Lower than petrodiesel NOx emissions (12g/kWhr) were attributable to most animal based feedstock, while higher NOx emissions were found using most vegetable based feedstock.  The average result again resulting in virtually a neutral NOx emission effect compared to petrodiesel.  
In addition, the lack of sulfur in biodiesel allows for nitrogen and nitrous oxide control techniques (eg. cetane enhancers or minor retardation of fuel injection timing by 1-2 degrees of crankshaft angle) that are typically ineffective with petrodiesel.

Energy

Depending on feedstock, as well as refining and blending process, the energy content of biodiesel (heating value: 31,250 BTU/litre) is approximately 8.5% lower than for No. 2 petrodiesel (34,200 BTU/litre).  This is not considered a major issue since engine performance is not derived from the heating value of diesel fuel, but rather its cetane number and density.
Having an average 30% higher cetane value and 5% higher density compared to petrodiesel, the reduced biodiesel energy efficiency is deemed negligible (eg: 4% for B100 and 0.5% for B20), especially considering the substantial health benefits gained.

Lifecycle

A total energy balance study undertaken by the University of British Columbia, using canola as biodiesel feedstock, determined that for every unit of fossil energy used in biodiesel production about 2.5 units of energy are gained when biodiesel is burned.
In comparison, the energy gain for petrodiesel yields only 0.85 units, and for gasoline about 0.75 units.  Thus confirming that biodiesel has the highest energy balance of commonly used liquid fuels.

Purchase

Biodiesel or biodiesel blends should only be purchased from certified and accredited vendors that will warranty applicable ASTM-6751, EN-14214 or BQ-9000 compliance.  Quality fuel will provide improved air quality and enhanced operation.  Random sampling and testing of delivered fuel should be performed on a regular basis.

Feedstock

Synopsis

Aside from significant investments currently funding the design of more efficient biodiesel production technology on a global scale, research is also being undertaken regarding production of synthetic biodiesel, as well as the development and cultivation of dedicated feedstock such as higher energy agricultural products and algae.  Presently, biodiesel uses mainly co-products or by-products generated from the oilseed crushing and rendering industries.
Common feedstock are oils derived from canola, rapeseed, soybean, sunflower, olive, linseed, sesame, peanuts, hemp, coconut, cotton seed, jatropha nut, palm kernel and used cooking grease, as well as from fish, poultry, pork and beef rendering fats.
Compared to oilseed derived biodiesel, fuel produced from tropical oils and animal fat typically have higher energy value, but decreased cold-flow operability.
The use of agricultural feedstock in the manufacture of biodiesel will provide substantial economic benefits to rural communities.  With respect to the use of animal renderings as feedstock, significant reduction in expensive waste disposal, as well as landfill and sewage treatment facility operation, will be realized.
Generally, feedstock delivered to a processing facility accounts for about 70% of overall biodiesel production cost.  Therefore, reliable, cost effective and reasonably close feedstock access is advantageous and desirable for biodiesel producers.

Canola

Canadian canola production in 2006 is estimated at about 4.5 million tonnes (10 billion pounds).  By 2015, this amount is expected to reach about 14.5 million tonnes (32 billion pounds).
Based on typical Canadian varieties and regional yields, canola production averages about 30 bushels/acre.  At 22 kg/bushel, this amounts to 660 kg of harvested seed/acre.  Once crushed, approximately 42% of that quantity, or equivalent 280 kg/acre, of canola oil is generated.  Based on 0.88 specific gravity, this converts to 320 litres/acre of canola oil for biodiesel production.
In comparison, average oil production for soybeans amounts to about 180 litres/acre; 450 litres/acre for rapeseed; 550 litres/acre for mustard seed; 650 litres/acres for jatropha nuts; 1,150 litres/acre for coconut oil; 2,500litres/acre for palm oil; and 55,000 litres/acre for algae.

Mustard

Because of being inedible, mustard oil is a low value waste product.  However, since it contains up to 90% mono-saturated fatty acids, it makes for a preferred biodiesel feedstock by exhibiting suitable cold flow properties and low nitrogen oxide emissions.  In addition, the meal left over after oil production is an effective biodegradable pesticide.

Soybean

Compared to canola, soybean feedstock has a higher fat and iodine content, as well as higher energy value.  Consequently, the result is less efficient combustion, greater nitrous oxide emissions, a higher cloud point and lower oxidation stability.

Handling

Blending

For blended biodiesel, best engine performance is achieved when homogeneously combined with petrodiesel. Mixing methods may consist of mechanical agitation or recirculation in the storage tank, splash blending in the storage tank or tanker truck, or proportional in-line blending at the dispensing location.
Under all scenarios, and especially winter conditions, both biodiesel and petrodiesel should be at similar temperatures during blending operations, in order to prevent shock crystallization (ie: potential gelling of the warmer fuel).   Ideally, blending should occur at approximately 5°C (10°F) above the applicable biodiesel cloud point temperature.  However, blending target temperatures need to be determined individually based on fuel type, as well as product and ambient temperatures.
It is quite common to use B20 blended with No. 2 petrodiesel (heating oil) during summer operation, and switch to B10 blended with No. 1 petrodiesel (kerosene) for winter use.

Safety

Biodiesel is considered a non-flammable and non-combustible product.
With a flash point temperature of 150°C (300°F) and higher, compared to about 50°C (120°F) for petrodiesel, close to 15°C (60°F) for ethanol and approximately -65°C (-50°F) for gasoline, neat biodiesel and biodiesel blends are substantially safer to store, handle and use compared to conventional petrodiesel, ethanol or gasoline.
Biodiesel soaked rags should be stored in safety containers, or dried individually prior to storage.  Otherwise, when combined into a pile, natural biodiesel oxidation can potentially produce enough heat to create spontaneous combustion.
Although comparatively safe to handle, skin and/or eye contact should be avoided, and inhalation shall be minimized.  It is recommended that during extended biodiesel exposure, face mask, safety goggles and suitable work attire should be worn.

Storage

Typical suggested shelf life of biodiesel and related blends should be around six months.  However, depending on product and storage conditions, up to 1 year may be acceptable.  Beyond that period, product degradation may occur resulting not only from oxidation, but also from increased acidity level and sludge formation due to bacterial and fungal growth.
Due to its unique oxygen-containing chemical structure (hygroscopic property), biodiesel has a stronger affinity for moisture absorption than petrodiesel, which in turn may cause potential discoloration, fuel contamination, increased viscosity, and acidic bacterial activity resulting in container corrosion.
The rate of biodiesel degradation may be reduced through the introduction of antioxidants, injection of biocides to counteract biological contamination due to formation of microbes at the fuel/water interface, the use of desiccant filters to eliminate moisture from air entering the tank, the removal of entrained water, or the installation of a nitrogen gas blanket system inside the storage tank.
In general, although depending on the feedstock used for biodiesel production, a safe storage and blending temperature would normally be around 10°C - 15°C (50°F - 60°F).  Even at temperatures above 70°C (160°F), biodiesel has shown minimal thermal instability and bacteria growth.
Sampling of stored product should be performed at regular intervals to ensure consistent fuel specification adherence.
Biodiesel storage should consist of a clean, dry and dark environment.  Acceptable storage tank materials include aluminum, carbon steel and stainless steel, as well as fluorinated polypropylene, fluorinated polyethylene, teflon and most fiberglass materials.
Except for excessive installation costs and potential  liability issues, most underground storage tank installations provide adequate heat loss prevention.  Aboveground containment facilities in cold climate locations require either insulation, agitation, heating, or a combination thereof.
Storage containers and associated components consisting of copper, brass, bronze, lead, tin and zinc, as well as elastomers such as polypropylene, polyvinyl, nitrile or natural rubber compounds, should be avoided.  Deterioration of such materials can cause potential containment failure or product contamination.

Transportation

Dedicated biodiesel tanker trucks and associated transfer components should be used to transport biodiesel.  If non-dedicated equipment is used, it must be washed, rinsed, drained and dried prior to biodiesel loading in order to avoid any cross-contamination.  Teflon, viton or nylon lined hoses have very little reaction to biodiesel, and are normally recommended for use.
Certain residual products related to vegetable oils, aromatic solvents, chemical surfactants and heavy fuel oils, to name just a few, will cause contamination and should never be allowed to remain in tankers at time of biodiesel loading.
For cold climate transportation, insulated and/or heated road or rail tankers should be considered.  Since reheating of gelled biodiesel is not recommended, it is also preferred that the neat or blended biodiesel temperature not drop below the applicable cloud point. 
Neat biodiesel is not considered a hazardous material for transportation purposes, and in reference to the National Motor Freight Classification (NMFC), the following descriptions are applicable:

Proper Shipping Name:	Fatty acid ester
Shipping Classification:	65
Identification Number:	144920

Unloading

Prior to transport unloading at destination, the receiver should consider:

• random fuel sampling (either for immediate and subsequent testing)
• match Bill of Lading (BOL) against product order
• confirm that Certificate of Analysis (COA) meets ASTM D6751 specifications
• check information on Material Safety Data Sheet (MSDS) is less than three years old
• question any noticeable discoloration or change in colour
• test product density

Although not part of ASTM D6751 guidelines, a density test will identify the inclusion of other petroleum products (eg. kerosene), and a visual appearance check may provide a preliminary clue regarding water or sediment contamination

Health

Exposure

Scottish researchers have determined that exposure (even only for one hour during exercise) to petrodiesel exhaust fumes, especially in concentrated form within large urban centers, blood vessel functions are significantly disrupted in their ability to expand (dilate).
In another study, conducted by Harvard University School of Public Health on adults in several U.S. communities during 1970’s and 1980’s, it was found that cities with decreased pollution levels of particulate matter (ie: soot) had an increase in lifespan of its residents.
A study by the U.S. Environmental Protection Agency’s National Center for Environment Assessment found that exposure to petrodiesel emissions posed a lung cancer hazard, irritation and inflammatory symptoms, as well as exacerbation of existing allergies and asthma conditions.
In addition, school districts that use biodiesel fueled buses reported a decrease in student and driver complaints regarding headaches and asthma attacks.

Inhalation

Tests performed by US based Southwest Research Institute and Lovelace Respiratory Research institute related to chronic inhalation studies, concluded that biodiesel, unless ingested as heated vapor, does not pose any threat to the environment and human health.  However, as a precautionary measure, personnel exposed to excessive biodiesel inhalation should be removed to fresh air.
Biodiesel emissions do not contain aromatic compounds and have therefore substantially reduced levels of PAH (polycyclic aromatic hydrocarbons) and nPAH (nitrated PAH) compared to petrodiesel, both identified as potentially cancer causing agents.
Also, Ames mutagenicity studies have shown biodiesel to dramatically reduce the potential of birth defects, as well as 90% cancer risks, in relation to petrodiesel tests.

Irritation

Based on USDA studies, 24-hour human patch tests indicated that undiluted biodiesel caused only very mild skin irritation – less than produced by a 4% soap/water solution.
Being organic, in lieu of fossil based, biodiesel is not offensive and avoids causing extensive nose, throat and eye irritation (as observed during  actual USDA field trials).
Areas of accidental biodiesel skin contact should be washed with soap and water, while eye contamination should be irrigated with water.  Seek medical attention if symptoms persist.

Toxicity

Evaluations performed by USDA (under the EPA Clean Air Act) determined biodiesel to be non-toxic, as well as about ten times less toxic than table salt (NaCl).

Market

Availability

Prior to 2007, Alberta played no significant part in commercial biodiesel production.  However, facilities are anticipated to be operating throughout the province by 2009 producing up to 650 million litres/year of commercially available, quality grade biodiesel.
On a national level, Canada’s 2006/2007 production is estimated at about 80 million litresof biodiesel, with indications by the Federal Government for a desire to have Canada produce a minimum 500 million litres/year by 2010.
In relation to Canada, U.S. biodiesel production reached almost 1.0 billion litres/year in 2006, and expected to increase to about 8.0 billion litres/year by 2010.
Europe, in the meantime, is already consuming close to 4 billion litres/year of biodiesel in 2006 (double the volume produced in 2004), with plans to encourage producers in doubling or tripling that amount by 2010.
In comparison, total petrodiesel consumption in Canada during 2006 is estimated at about 60 billion litres (with almost 45% allocated to transportation), while in the U.S. the total amount is estimated at about 300 billion litres.

Consumption

In terms of present usage, Alberta consumes approximately 5 billion litres/year of petrodiesel, with the majority allocated to the commercial transportation industry.
Based on the federal government’s mandatory introduction and use of a B2 blend (2% biodiesel; 98% petrodiesel), the present Alberta market alone will require biodiesel production of at least 100 million litres/year.  A B5 blend would consume about 250 million litres/year of biodiesel.

Global

Albeit slowly, biodiesel has enjoyed a steady and substantial resurgence in popularity during the last couple of decades.  The U.S. Department of Energy has even pegged it as the fastest growing source of alternative fuel.
The major concentration of biodiesel usage will apply to overland freight transportation.  However, biodiesel will also play a major role in replacing significant amounts of petroleum based fuels in the near future related to general public transportation, power generation, home heating systems and the construction industry, as well as environmentally sensitive marine and mining sectors.
Although being the fasted growing biodiesel market in the world, U.S. biodiesel volume consumed in 2006 is estimated at only about 0.5% of all on-road petrodiesel sold – allowing for substantial future market penetration.
Various legislative incentives, from municipal to national levels world wide, have greatly assisted in the rapid expansion of the biodiesel industry in recent years, which seems to show no signs of slowing down.

Performance

Compatibility

he use of biodiesel, either in pure or in blended form, requires no modifications to diesel engines (manufactured since 1996).  However, biodiesel contact with natural or butyl rubber components (eg: fuel hoses and pump seals) is not recommended in excess of B20 blends, since it will cause certain elastomers to soften and degrade with prolonged exposure.  Contact with copper, brass, bronze, lead, tin and zinc materials should also be avoided for similar reasons.

Efficiency

In general, diesel engines provide the backbone of all major global transportation systems, as well as outperform gasoline engines by a factor of about 1.5 to 1, and ethanol powered equipment in the range of 2 to 1.  In addition, neat or blended biodiesel imparts the extra benefits of lower toxic emissions and increased engine life.
In relation to regular diesel engines, neat or blended biodiesel operational tests have shown comparable performance results for fuel economy and torque generation, and minimal power loss of only about 5%.  With the introduction of ultra-low sulphur diesel, the difference in power loss is expected to become virtually negligible.

Ignition

Having a higher cetane number compared to petrodiesel (42 for petrodiesel vs. 52 to 56 for vegetable oil and animal fat, respectively), as well as about 10% oxygen content by weight, biodiesel provides easier starting, improved ignition, quieter engine operation and lower emissions.

Lubricity

Since the federal government’s 2006 mandate of 15ppm maximum sulfur content for diesel operated highway vehicles (and a 2010 deadline for off-road vehicles),North American petrodiesel, which according to a Southwest Research Institute (1998) is already considered one of the poorest lubricity fuels worldwide, requires the addition of performance enhancing additives to achieve acceptable lubricity levels in order to avoid premature equipment deterioration.
Biodiesel, in comparison, contains natural lubricating compounds that have shown to increase the longevity of engine components in contact with the fuel,reduce operating temperature, decrease maintenance, and provide quieter operation.
Engine cylinder wear tests, using oil, grease and fat as biodiesel feedstock, have shown an average reduction in scar depths of about 20% using B2 (from 0.41mm to 0.33mm);  about 45% for B5 (from 0.41mm to 0.23mm); about 55% for B20 (from 0.41mm to 0.18mm); and about 60% for B100 (from 0.41mm to 0.16mm).
Biodiesel, therefore, offers an ideal solution to existing petrodiesel lubricity problems, while at the same time supporting environmental, energy and economic development initiatives.
Also, preliminary field tests using blended biodiesel and ultra-low sulfur diesel (ULSD) have indicated positive engine performance results to date as well.

Maintenance

Over time, petrodiesel leaves sediment in tanks, pumps and fuel lines.  Biodiesel, being a mild solvent, may dissolve these deposits and clog fuel filters during initial operation.
Precaution should be taken to check and replace plugged filters while using the first few tanks of neat or blended biodiesel, until the system is cleaned of petrodiesel deposits.
In order to avoid prolonging the cleansing and filter clogging period, it is normally suggested to use the desired blend from the outset, rather than gradually phasing in biodiesel using weaker blends first. 
Although no special operational precautions are required in handling biodiesel, regular maintenance on storage tanks, distribution piping, transfer pumps and operating equipment should be performed, the same as with petrodiesel.

Warranty

Presently, warranty by various Original Equipment Manufacturers (OEM’s) of diesel engines (eg: Cummins) has been approved for up to B5 blended fuels.  Most have also affirmed that the use of B20 would not void their warranty, although tests are still being evaluated.
In addition, Diesel Fuel Injection Equipment Manufacturers, such as Bosch and Stanadyne, have indicated support for neat and blended biodiesel in consideration of the fact that any adverse consequences, such as may occur with excessive use of lubricity additives, is potentially avoided.
John Deere has plans to use B2 as the preferred factory-fill in all their diesel engines, New Holland and Case-IH have announced full support of B20 in their diesel equipment, and DaimlerChrysler has approved use of B20 fuel in select 2007 Dodge Ram truck models.
Note:  The use of biodiesel does not affect the OEM’s Material and Workmanship warranty.  However, no warranty will cover fuel related equipment failure, regardless of fuel type, if non-compliant (ie: non-regulated or off-specification) fuel or additives are being used.

Processing

Conversion

A typical oily feedstock conversion process will result in generating approximately 90% neat biodiesel and 10% crude glycerin.
Similarly,1.0 kg of prepared feedstock(oilseed, animal fat or cooking grease) reacted with 0.10 kg of alcohol (methanol or ethanol), in the presence of a catalyst (potassium or sodium hydroxide), generally produces about 1.1 litre biodiesel and 0.10 litres glycerin.
The alcohol and catalyst are introduced into the oily feedstock to ensure the successful conversion of virtually all fat to useable methyl ester (biodiesel) and glycerin.  Typically, methanol (having shorter carbon chain molecules) is more reactive than ethanol.

Production

Typically, biodiesel production consists of reacting fats with an alcohol and a catalyst in a slightly agitated, pressurized and heated environment.  Processing conditions may vary somewhat depending on the type of feedstock and production method employed.
The resulting transesterification process, normally incorporating sodium hydroxide (caustic soda) and methanol, causes the majority of glycerin in the feedstock to be replaced with an alcohol component, thus creating two main saleable products, biodiesel and glycerin, which are subsequently separated using a gravity or centrifuge method.
To meet applicable quality standards, further reduction of the glycerin content may be necessary.  This may simply be accomplished through biodiesel ‘washing’, either via the addition of water, introduction of powdered magnesium silicate, or contact with ion resin, and additional product separation, if required, using a centrifuge or straining system.
Glycerin, typically only about 85% pure (crude glycerin) and presently not considered a highly priced commodity, has over 1,500 known end uses and is applied extensively in the manufacture of soap, paint, toothpaste, antifreeze, shampoo, candles, lubricants, inks, cleaners, solvents, polishes, textiles, biodegradable plastics, etc.  In more sophisticated operations, glycerin is distilled to 99% or higher purity and sold into cosmetic and pharmaceutical markets.
Other possible considerations for glycerin being investigated are for use as a heating fuel, animal food supplement and low-grade non-toxic fertilizer, which in turn has the potential of creating minor sources of additional revenue.

Properties

Attributes

Indicated data (with conversions rounded to approximate equivalent values) represent typical ‘averages’ determined from different evaluation tests and may vary depending on feedstock and/or processing method used:

	Biodiesel (B100)	Petrodiesel #1 (Kerosene)	Petrodiesel #2 (Heating Oil)
Flash Point	150°C (300°F)	45°C (110°F)	50°C (120°F)
Boiling Point	200°C (390°F)	230°C(450°F)	300°C(570°F)
Specific Gravity	0.88	0.82	0.85
Cetane Number	50 – 60	45	47
Typical Color	Amber	Yellowish	Yellowish
Odor	Light/Musty	Strong/Pungent	Strong/Pungent

Note:  The Flash Point temperature of a B20, or lower, biodiesel blend is close to petrodiesel.

	Cloud Point	Pour Point	Cold Filter Plugging Point	Kinematic Viscosity @ 40°C (105°F)
Petrodiesel (#2)	-20°C (-5°F)	-25°C (-15°F)	-20°C (-5°F)	2.0 cSt
Biodiesel (Canola)	-5°C (+25°F)	-4°C (+25°F)	-4°C (+25°F)	2.0 cSt
Biodiesel (Soybean)	+2°C (+35°F)	-1°C (+30°F)	-1°C (+30°F)	3.0 cSt
Biodiesel (Grease)	+10°C (+50°F	+5°C (+40°F)	+5°C (+40°F)	4.0 cSt
Biodiesel (Tallow)	+15°C (+60°F)	+20°C (+70°F)	+15°C (+60°F)	6.0 cSt

Note:  1 cSt (centistoke) = 1 mm2/s
For vegetable based feedstock, the Cloud Point temperature for a B20 biodiesel blend is typically lower by about 25C° (50F°) compared to B100.  For animal based feedstock, it is about 30C° (60F°) lower.  For B5 blends, the cloud point temperature can generally be reduced by an additional 5C° (10F°), compared to B20.

Conductivity

In low conductivity fuels (eg: petrodiesel and gasoline) electrical charges can accumulate and discharge in the form of a spark (during pumping and filtering).  To avoid such potential creation of a fire hazard, static dissipater (conductivity) additives are commonly mixed into the fuel.
In comparison, neat biodiesel has sufficiently high conductivity that a static dissipater is typically not required for blends of B20 and above, due to the increase in electrical conductivity imparted by the biodiesel fuel component.

Specification

Present North American ‘biodiesel’ specifications must adhere to existing American Standard Testing and Material (ASTM D-6751-06b) code requirements:

	Test Method	Limits	Units
Flash Point (closed cup)	D-93	93.0 min.	°C
Water & Sediment	D-2709	0.050 max.	% volume
Kinematic Viscosity @ 40°C	D-445	1.9 – 6.0	mm2/s
Sulfated Ash	D-874	0.020 max.	% mass
Sulfur:  S15 Grade	D-5453	0.0015 (15) max.	% mass (ppm)
Sulfur:  S500 Grade	D-5453	0.05 (500) max.	% mass (ppm)
Copper Strip Corrosion	D-130	No. 3 max
Cetane Number	D-613	47 min.
Cloud Point	D-2500	(Report)	°C
Carbon Residue	D-4530	0.050 max.	% mass
Acid Number	D-664	0.500 max.	mg KOH/gm
Free Glycerin	D-6584	0.020 max.	% mass
Total Glycerin	D-6584	0.240 max.	% mass
Phosphorus Content	D-4951	0.001 max.	% mass
Distillation Temperature (90% Recovery)	D-1160	360.0 max.	°C
Sodium/Potassium (combined)	EN 14538	5 max.	ppm
Calcium & Magnesium	EN 14538	5 max.	ppm
Oxidation Stability	EN 14112	3 min.	hours

Note:  Specifications may be randomly modified by the ASTM organization.  Regular monitoring of the applicable code(s) should be implemented by biodiesel producers.

Viscosity

All diesel cold flow properties are usually measured using either the Cloud Point (CP) or Cold Filter Plugging Point (CFPP) temperatures.
Cloud Point references the temperature at which the first visual observation of small crystal formation (visible haze) is made.
Cold Filter Plugging Point references the temperature at which the fuel filter will start to plug due to fuel components beginning to crystallize or gel.  Typically, this temperature is almost identical to the Cloud Point of the respective biodiesel products.
Some leading options to handle cold flow problems consist of blending with No. 1 petrodiesel (kerosene), injection of cold flow enhancement additives, or continuously subjecting fuel and vehicles to a heated environment.
The addition of cold flow enhancement additives (eg: paraffin-like structures such as acetate) normally does not affect the formation, size or shape of crystals, nor the Cloud Point temperature.  Additives merely inhibit the agglomeration process of smaller crystallized paraffin molecules into larger ones and thus effectively only lowering the Cold Filter Plugging Point temperature, but not the Cloud Point temperature.
When using B20 blends or lower, cold weather performance is typically dictated by the diesel fuel portion, and therefore no unusual operational problems are normally encountered in addition to those experienced using straight petrodiesel.