On a molecular level, plant oils and animal fats are too large to burn efficiently in a modern diesel engine. This is why vegetable oils and animal fats are combined with alcohol and a catalyst to create a reaction called transesterification.  This process breaks down the oil molecules into chains of smaller, lighter molecules.  This resulting product is called biodiesel (Mono Alkyl Esters).

To be certified as a fuel, biodiesel must be produced to meet national standards.  The most generally accepted standards are the American ASTM 6751 and Europe’s EN14214.  To be legally recognised and registered as a fuel in Australia, all biodiesel must meet or exceed these standards.

Biodiesel has a favourable energy balance ratio.   An energy balance ratio compares the energy required to grow or extract, process and distribute a fuel as compared to the energy stored in that fuel.  Biodiesel contains 2.5 to 3.5 units of energy for every unit of fossil energy input in its production.  This value includes energy used in diesel farm equipment and transportation equipment, fossil fuels used to produce fertilizers, pesticides, steam, and electricity, and methanol used in the manufacturing process of the biodiesel itself.

When biodiesel displaces petroleum, it significantly reduces Greenhouse Gas Emissions.  Biodiesel tailpipe emissions are substantially cleaner and safer than fossil diesel and petrol powered vehicle emissions.  Burning biodiesel emits no sulfur dioxide, 78% less carbon dioxide and as much as 50% fewer smog producing compounds than conventional diesel and petrol.  The U.S. EPA’s study of biodiesel emissions confirmed a 47% reduction in particulates and a 48% reduction in carbon monoxide when compared to fossil diesel emissions.

The use of ProGreen's Biodiesel eliminates or reduces the levels of harmful compounds contained in diesel exhaust.  Consequently, biodiesel use can eliminate or reduce illness associated with short and long term exposure to diesel fumes, such as nausea, headaches, respiratory problems, asthma and even cancer.  Research has shown that burning 100% biodiesel reduces the risk of cancer linked to diesel vehicle emissions by as much as 94%.  Specifically biodiesel use dramatically limits exposure to carcinogenic hydrocarbons, respiratory irritants such as particulate matter and poisonous gases such as carbon monoxide.

Biodiesel is biodegradable and nontoxic.  It contains no hazardous materials.  In fact B100 is as biodegradable as dextrose (sugar) and less toxic than table salt.  Several studies have shown biodiesel to biodegrade up to four times faster in water than petroleum diesel fuel with up to 98% biodegrading in three weeks.  The reduced emissions, pleasant odour, biodegradability, and safety of biodiesel make it well suited for use in marine environments and sensitive ecosystems.

Frequently asked Biodiesel Questions

What is Biodiesel?

No. Biodiesel that meets or exceeds international standards (ASTM 6751, EN 14214) can be utilised in all diesel engines, providing specific change over and ongoing maintenance procedures are followed.

All diesel engine companies warranty the product they make - engines. They warrant their engines for “materials and workmanship.” If there is a problem with an engine part or with engine operation due to an error in manufacturing or assembly within the prescribed warranty period, the problem will be covered by the engine manufacturer.  Thus, if an engine using biodiesel experiences a failure unrelated to the biodiesel use it must be covered by the OEM’ s (Original Engine Manufacturer’s) warranty.  Federal law prohibits the voiding of a warranty just because biodiesel was used—it has to be the cause of the failure. Since engine manufacturers warrant the materials and workmanship of their engines, they do not warrant fuel of any kind. If there are engine problems caused by a fuel (again, whether that fuel is petro-diesel fuel or biodiesel fuel) these problems are not related to the materials or workmanship of the engine, but are the responsibility of the fuel supplier and not the engine manufacturer. Any reputable fuel supplier (biodiesel, petro-diesel, or a blend of both) should stand behind its products and cover any fuel quality problems if they occur.

Biodiesel can be made from a variety of renewable sources such as plant oils, recycled cooking grease or animal fats.

Canola is the primary oilseed used as feedstock for biodiesel in Australia.  Current 12% of canola production in Australia is used in biodiesel production. Canola seed is produced as part of the canola crop and represents a small part of the total crop biomass. Approximately 40% of the seed is made up of oil content. Though the seed is clearly the primary product from canola, the other parts of the plant, the straw and stump and root material also provide economic benefits.  The straw may be used for feed, or as an energy source in the production of biodiesel     

Tallow is rendered animal fat and a   by-product of the livestock processing industry.  Australian tallow production in 2000-2001 was approximately 567,000 tonnes and most was exported (68%). The biodiesel yield from the tallow is approximately 894 litres per tonne.

Used cooking oil is also known as waste cooking oil. One tonne of waste oil yields approximately 870 litres of biodiesel.  It is difficult to determine the quantities and value of used cooking oils as some businesses incur costs to dispose of the oils while others are paid for theirs.  On the basis that waste oil is produced at a rate of between 10-12 litres per person, total Australian supplies would be between 220 and 260 mega litres in 2010. 

The question of sustainability is a broad subject that can be open for interpretation from very different aspects.  From the perspective of fuels, it can be argued that biodiesel is more sustainable than fossil fuels as they economically stimulate a wider domestic cross section of the community, they produce less Greenhouse Gases, and when carbon is generated from biodiesel, it is sequestered back into the energy crops (or animals) as part of the life cycle production of biodiesel.

Biodiesel has an approximate 8% lower energy content than that of petroleum based diesels, which would suggest that fuel economy would drop slightly but in field tests it has been found that higher cetane numbers of biodiesel can offset some or all of this effect.