Truck Topics

Biodiesel Update

Unless you've been marooned on a deserted south Pacific island for the last decade or so, you've probably seen some mention of biodiesel when reading or watching the news. 

In fact, in the world of trucking news, this alternative fuel is spotlighted on an almost daily basis, with news of another biodiesel plant being planned/built or another U.S. municipality switching its public works trucks from conventional diesel fuel to biodiesel.

Biodiesel production in the United States tripled between 2004 and 2005, from 25 million gallons to 75 million gallons.  An estimated 150 millions will be produced in 2006.  Currently there are 65 biodiesel plants operating, with another 90 plants

proposed or under construction. There are close to 1,600 distributors that offer biodiesel, and according to the National Biodiesel Board, the leading advocacy group of the fuel, there are more than 340 truck-accessible fueling sites.

The law
Minnesota was the first state in the nation to mandate the use of biodiesel. The 2002 Legislature passed a law requiring all diesel fuel sold in the state contain at least 2 percent of the product made from soybeans. The law kicked in September 2005, once the production from Minnesota's three biodiesel plants reached sufficient capacity.

The switch did not go as smoothly as planned however, with truckers reporting clogged fuel filters, resulting in a temporary suspension of the mandate while the problem was investigated. 

Minnesota officials concluded that the problems were isolated to a few specific batches of fuel from Minnesota biodiesel producers who took some shortcuts.  Some biodiesel that did not meet quality specs made its way into the supply, and it resulted in a significant number of trucks breaking down. Filter plugging was a big issue, and it was found that off-spec biodiesel was part of the problem.

Biodiesel background
It's a clean-burning fuel, produced from domestic, renewable resources, say biodiesel advocates.

It contains no petroleum, but it can be blended at any level with petroleum diesel to create a biodiesel blend. It can be used in diesel engines with little or no modifications. Biodiesel is biodegradable, nontoxic, and essentially free of sulfur and aromatics.

Biodiesel fuel is produced by alcohol — usually methanol or ethanol — chemically reacting with vegetable oils, animal fats or recycled cooking greases. It can be used neat (pure) or blended with petroleum-based diesel fuel.

The most popular type of biodiesel now used is a 20 percent blend, or B20. It’s also used in a 2 percent blend with diesel, primarily for added lubricity.Biodiesel has about 90 to 95 percent of the energy content found in No. 2 diesel. 

Since biodiesel has a lower energy content, it will require about 1.1 gallons of fuel to do the same work as 1 gallon of diesel fuel.  It has a high cetane number (related to ignition capabilities) and offers good lubricating qualities. Biodiesel suppliers say a 2 percent blend of biodiesel may replace the lubricity lost with low-sulfur fuels.

The fuel is sensitive to cold weather and requires anti-freezing treatments. Biodiesel acts like a detergent additive and will loosen and dissolve fuel tank and fuel line sediments. It also acts like a solvent and may pose problems for seals and other rubber components in pre-1994 engines.

Fuel-grade biodiesel must be produced to strict industry specifications (ASTM D6751) in order to insure proper performance. Biodiesel is the only alternative fuel to have fully completed the health effects testing requirements of the 1990 Clean Air Act Amendments. Biodiesel that meets ASTM D6751 and is legally registered with the Environmental Protection Agency is a legal motor fuel for sale and distribution.

The National Biodiesel Board has its own voluntary quality specifications, known as BQ-9000. The standards are part of the National Biodiesel Accreditation Program, which is run by the Biodiesel Board.

Biodiesel is better for the environment, say its proponents, because it is made from renewable resources and has lower emissions compared to petroleum diesel. It is less toxic than table salt and biodegrades as fast as sugar. Since it is made in the USA from renewable resources such as soybeans, its use decreases our dependence on foreign oil and contributes to the U.S. economy.

Source: U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy

Some doubters
Not everyone is  biodiesel bandwagon however, including David Pimentel, professor of ecology and agriculture at Cornell, who says, "There is just no energy benefit to using plant biomass for liquid fuel. These strategies are not sustainable."

He refers to to a Cornell University and University of California-Berkeley study that concluded that turning plants such as corn, soybeans and sunflowers into fuel uses much more energy than the resulting ethanol or biodiesel generates.

In terms of energy output compared with the energy input for biodiesel production, the study found that:
* soybean plants requires 27 percent more fossil energy than the fuel produced, and
* sunflower plants requires 118 percent more fossil energy than the fuel produced.

"The United State desperately needs a liquid fuel replacement for oil in the near future," says Pimentel, "but producing ethanol or biodiesel from plant biomass is going down the wrong road, because you use more energy to produce these fuels than you get out from the combustion of these products."
 
The American Trucking Association is restrained in its enthusiasm for biodiesel.  It supports the use of biodiesel that meets ASTM quality standards, but only in blends of up to 5 percent biodiesel, also known as B5.

"Though it is certainly not a complete answer to our dependence on foreign oil, it is one tool we should use in our toolbox. Last year the biodiesel industry produced 75 million gallons of biodiesel. Last year the trucking industry alone used 36 billion gallons of diesel fuel. Even if biodiesel doubles this year and doubles again, it is unlikely to be the answer to our quest for energy independence," says a spokesman for the ATA.

What say the OEM's?
Most of the major truck engine manufacturers, including Caterpillar, Cummins and Detroit Diesel have policies in place regarding the use of biodiesel in their engines and are continuing research into the subject.

While B20 – a 20-percent blend of biodiesel – is a popular blend among retailers, that popularity doesn’t necessarily extend to engine manufacturers.

The Engine Manufacturers Association (EMA) recommends a blend of no higher than B5, and most manufacturers seem to agree. They are holding to the position that, until a national standard for quality assurance is developed, they won’t officially recommend any biodiesel product higher than a B5 blend.

The EMA’s recommendations state that higher biodiesel blends could cause problems such as filter plugging, piston ring sticking and breaking, and elastomer seal swelling.

Now that ULSD is here
Another unresolved issue, says the EMA, is that of ultra-low-sulfur diesel.

The Biodiesel Board said in its official statement on ULSD that biodiesel contains virtually no sulfur, so it shouldn’t be an issue.

What’s more, the board maintains that biodiesel can help with one of the key problems facing the switch to ULSD: lubricity.

Removing the sulfur from diesel seriously lowers its lubricity, which can gum up the inner workings and cause serious problems for engines. The Biodiesel Board’s statement says biodiesel has a higher lubricity than ULSD, even in low blends.

The board said that a study done by Stanadyne Automotive Corp. – a manufacturer of diesel engine components – found that a 2-percent blend of biodiesel could increase lubricity by as much as 65 percent.

The new particulate filters in the 2007 engines pose another potential problem. The engine manufacturers are still testing and researching, but if the problems in Minnesota are any indication, biodiesel will still have to prove itself to many.