Biodiesel is the fastest growing alternative fuel source, especially in Europe where strong mandates and a fleet that utilizes primarily diesel has created a strong demand. Increasing demand is also being seen from the airline industry, which views the use of biofuel as a means of mitigating carbon emissions.

Biodiesel, a methyl ester, is created by chemically altering the molecular structure of vegetable oils (both virgin and used) and animal fats. Biodiesel can be used in any standard diesel engine either pure or mixed in any proportion with petroleum diesel without any necessary engine overhaul. Biodiesel contains no sulfur or aromatics and has passed the EPA required Tier I and Tier II health effects testing under the 1990 Clean Air Act 211(b).

The benefits of utilizing biodiesel are many and include the following:

  1. Increased engine benefits. Biodiesel acts as a solvent that cleans the engine and also acts as a lubricant, cutting down vehicle maintenance costs. Biodiesel burns cleaner. The higher cetane value of biodiesel means that the engine starts up much faster in a colder climate.

  2. Biodiesel is a renewable resource. Growing feedstock that can be converted into biodiesel reduces foreign oil dependence.

  3. Biodiesel offers an additional outlet for agricultural production. Fallow land can be placed back into production, creating additional employment and revenues for farmers.

  4. Reduces emissions. Worldwide emissions of greenhouse gasses have been increasing. In the US atmospheric carbon dioxide increased from 280 parts per million (ppm) in 1850 to 380 ppm in 2006. In the European Union, emissions increased 8% from 1990 to 2001, with the transport sector accounting for over 21%.  Biodiesel offers a solution to the growing environmental concerns, as described in a EU (European Union) report: “…biofuels represent the only solution available in order to reduce GHG and CO2 emissions from the transport sector….” US studies suggest that biodiesel cuts carbon emissions by 80% compared to fossil diesel; the scant carbon dioxide released into the atmosphere is recycled by the same plants that produced the oil used in the biodiesel production process. In addition, biodiesel does not release sulfur or lead into the environment when burned. The carcinogenic impact is greatly reduced when biodiesel is burned.

  5. Environmental impact. Biodiesel biodegrades as quickly as sugar and it is 10 times less toxic on the environment than table salt.

  6. Biodiesel is safe to handle. When compared to petroleum diesel, biodiesel has a higher flash point and is thus much safer to transport and handle. Biodiesel is considered non-hazardous under OSHA (Occupational Safety and Health Administration) criteria.

Biodiesel clearly offers a clean-burning alternative to petroleum diesel.

Biodiesel Process

Biodiesel can be made from virgin vegetable oils, used cooking oils and rendered animal fats, including tallow. The oils or fats are mixed with methanol in the presence of a catalyst. The esterification process results in the production of biodiesel and glycerin. The glycerin needs to be separated from the biodiesel at some stage of production. The raw biodiesel then needs to be washed to remove soapy substances and impurities. After washing, the biodiesel is dried. Some stages can be omitted in the process but quality is compromised.

Standard Biodiesel Production Method :

The biodiesel requires that oils or fats, methanol and a catalyst be mixed, heated and agitated. As the compounds come into contact with the oil or fats, biodiesel and glycerin are formed. The glycerin is then decanted, the alcohol is recovered and the biodiesel is washed and dried. This process can be performed chain-like, with batch after batch creating a continuous-like affair, or using a continuous process.

Feedstock :

Most biodiesel manufacturers rely on a single feedstock; changing from one oil or fat type to another can be a complicated process that requires shutting the production plant down, cleaning all of the equipment and then starting the operation back up. Feedstock flexibility is important because it can reduce production costs and time significantly. Biodiesel produced from different feedstock can have different properties. As an example, biodiesel manufactured from palm sterin has a cetane number of 85 whereas biodiesel manufactured from sunflower oil has a cetane number of only 52. Cold flow properties also vary depending on feedstock. Jatropha oil produces a biodiesel that is superior to most other oils or fats. Producing biodiesel that meets or preferably exceeds current technical standards is the key, as blending biodiesel that is out of spec can seriously impugn the reputation of the oil company blending the product and also affect engine operation; most biodiesel is currently marketed through leading oil companies, rather than directly to the consumer by the manufacturer. European standards are much more stringent than the standards in the US; European biodiesel must meet specification EN 14214, which tests for 28 different parameters whereas in the US ASTM D6751 only requires that 14 parameters must come within guidelines that are much broader than their European counterparts.

The European Biodiesel Market :

Biofuels are the core of the EU energy policy, and in 2003 the EU Commission set a blending target for biodiesel at 5.75% by 2010 and 10% by 2020. A 10% mandate for renewable content in transportation fuels is part of the new 20-20-20 plan that calls for a 20% reduction in greenhouse gas (GHG) emissions for all energy compared with 1990 levels, a 20% increase in the use of renewable energy and a 20% cut in energy consumption through improved energy efficiency. The 10% mandate for renewable content in transportation fuels replaces the voluntary targets of 5.75 percent by 2010 and 10 percent by 2020. The growth of the EU biodiesel industry is expected to go from 2.5 billion Euros in 2005 to 16-17 billion Euros by 2015. The underpinning forces to switch to biodiesel are the need to increase domestic energy security, reduce greenhouse gasses and address the shortage of diesel refining capacity. Biodiesel is regarded as having a much brighter future than ethanol, given the increasing diesel demand across the EU, an increasing shortage of diesel refining capacity in the EU, and the ability of the existing oil distributors to use biodiesel without any changes to the existing infrastructure.

US The Biodiesel Market

The biodiesel industry in the United States is relatively young. According to the Department of Energy 500,000 gallons of biodiesel were produced in 1999. By 2005 production totaled over 50 million gallons. The use of biodiesel is now mandatory; the Environmental Protection Agency (EPA) requires that in 2011 a total of 800 million gallons of biodiesel be blended into diesel, this representing just under 2% of the total diesel consumption. The US currently provides a $1.00 excise tax credit per gallon of biodiesel produced.

Biodiesel in the Diesel Market

The EPA (Environmental Protection Agency) established a dramatic sulfur reduction in diesel fuel effective in October 2006; the reduction went from 500 ppm (parts per million) to 15 ppm, or a 97% decrease in acceptable sulfur levels. The elimination of the sulfur will also affect lubricity. Biodiesel, even in low blends, can act as a lubricity additive in ultra low sulfur diesel; a 1% biodiesel blend can improve the lubricity in diesel by as much as 65% according to tests performed by Stanadyne Automotive Corporate. Biodiesel has no sulfur. Biodiesel can also be used to improve cetane number in poor grade diesel.