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A hard look at biodiesel

It's expensive and can gum up a truck's engine, but it is also easy to use and could reduce our dependence on foreign oil

Mike DeSimone is about as rock-ribbed a trucker as you can get. He grew a six-truck afterthought to his Oregon produce business into Cross Creek Trucking, a 100-tractor refrigerated fleet hauling produce and perishables up and down the I-5 corridor on the West Coast.

These days, DeSimone is focused on reducing his fleet's use of use of petroleum-based fuels. “I want to do something different. If they came out with a nuclear-powered truck I'd try it,” he says.

For now, though, the fastest and easiest way for DeSimone to cut petroleum consumption is to run the fleet on biodiesel, primarily B20, which contains 20% soybean-based fuel and 80% regular diesel. Cross Creek has used more than 50,000 gallons of biodiesel annually for each of the last two years and has experienced no degradation in vehicle performance, even when it filled tanks with to B50 at times.

Cost has become a factor, however, and could actually force the fleet to cut back on biodiesel or stop using it altogether. The carrier initially paid a 10- to 20-cent per gallon premium for biodiesel, but that changed when diesel prices went through the roof following Hurricanes Katrina and Rita in late 2005, and again this past summer. This led to a sudden spike in the demand for biodiesel, particularly for off-road equipment in the farming sector, and as a result the cost of biodiesel jumped disproportionately.

Those price swings played havoc with Cross Creek's bottom line. “The pricing fluctuations really frustrate us,” says DeSimone. “If we could just flatten the price of biodiesel, then we could adjust our [freight] pricing to cover it. But when prices soared, we had no choice and had to go shopping [for cheaper diesel]. I work as hard as I can to use it, but I've got a business to run as well.”

What, exactly, is biodiesel? The technical definition sounds something like “mono-alkyl esters of long-chain fatty acids derived from animal fats or vegetable oil” made from soybeans, canola, or sunflower seeds, for example.

Pure biodiesel (B100) is made strictly from these plant or animal-based extracts. In practical use, however, biodiesel refers to fuel that is made from a combination of the plant or animal extracts and petroleum-based diesel.


Biodiesel is a good fit for trucks because their diesel engines use super-high air compression to ignite fuel, rather than the spark plugs found in gasoline engines. This means there's much more leeway in terms of the type of fuel that will work in a truck, which is not the case for gasoline-powered vehicles.

“It's the quality of the fuel that is important,” says Glenn Lysinger, chief compliance officer for Detroit Diesel Corp. “If the fuel is made correctly, is of a consistent quality so it'll burn evenly and not leave residue, the engine is insensitive to where it came from.”

When virgin oil is used, quality is usually not an issue. But if you're using a pre-used feedstock — cooking oil from a fast-food chain, for example — it has to be processed properly or the pre-used oils can deteriorate or become contaminated, leading to fuel injector damage from deposit buildup, Lysinger explains. Those deposits, which come from the glycerin found in natural oils, must be separated from the raw stock so there's minimal residue when the fuel burns.

Although there is always some amount of glycerin left in the product, this is not a problem because it can serve as a lubricity agent. Lysinger points out that this is particularly important in light of the switch to ultra-low-sulfur-diesel (ULSD) because sulfur served as a lubricant for internal engine components.

Glycerin also makes biodiesel something of a solvent, removing deposits from fuel tanks, pipes and injectors. “It typically takes two fill-ups with biodiesel to wash out the deposits in a truck's fuel system,” adds Lysinger.

However, depending on the amount of deposits in the fuel, the filter could clog up, thus reducing engine power. “That's a fairly simple problem to fix,” he points out. “You just replace the filters.”

Cold weather performance is a concern because B20's cloud point — the temperature at which it begins to gel or become waxy — is about three or four degrees higher than straight diesel, says Ric Hiller, equipment chief for Arlington County, VA, which uses biodiesel in its fleet. “To combat that, our fuel supplier adds a special arctic chemical package that includes a gelling inhibitor,” he explains.

Another big issue is cost. Arlington County, which started using biodiesel in 2002, pays an extra 25¢/gal. for biodiesel, although this is partially offset by a federal tax credit based on a rate of $1/gal. of pure biodiesel (B100).

“Many fleets will pay five to ten cents more per gallon to thumb their noses at OPEC,” says Allen Schaeffer, executive director of the Diesel Technology Forum. Go above that ten-cent premium, however, and the economic impact starts looming a lot larger. “Every fleet needs to evaluate the cost of biodiesel vs. the green factor,” he says. “That's why, for the moment, biodiesel remains niche-market fuel.”

That leads to energy content and emissions issues. Pure biodiesel has 6% to 8% less energy content than regular petroleum diesel, says DDC's Lysinger. For blended biodiesel, however, that gap narrows considerably. “At the B20 level, the difference is almost negligible.”

As the concentration of biodiesel rises, particular matter (PM) is reduced substantially, but oxides of nitrogen (NOx) go up. “At a B5 or B10 blend, the NOx difference [between biodiesel and regular diesel] is negligible,” he says. “At B20 and higher, there's a measurable NOx increase.”


For trucking, fuel quality is the big hurdle. If biodiesel doesn't meet established standards, chances are it's going to raise havoc and leave trucks on the side of the road.

This is exactly what happened in September 2005 when Minnesota's mandate that all diesel sold in the state contain at least 2% biodiesel went into effect. Almost immediately, truckers that bought diesel in Minnesota had all kinds of problems.

Tom Chrismer, vp of Hudson, WI-based Valley Cartage told The Pioneer Press that the engines in its 50 trucks sputtered as fuel filters became plugged with “slimy gunk”; the problem worsened as winter descended. “We had trucks that couldn't make it up a hill,” he said, adding that the fleet went through 50 fuel filters in a month with no improvement in vehicle performance. “When we stopped using the blended fuel, our problems went away.”


Realizing that it had a major nightmare on its hands, the biodiesel industry helped obtain a 120-day suspension of the Minnesota mandate to give it time to fix the problem.

“The good news is that everything is now working fine so far,” says John Hausladen, president of the Minnesota Trucking Assn.

“But we haven't had really cold weather yet, so we'll see. This is exactly why a boutique fuel approach is a bad idea for interstate carriers,” he says. Hausladen feels strongly that if you want fleets to use biodiesel, you need to establish a national standard. “We learned some hard lessons,” he adds.

According to DTF's Schaeffer, “Most of the energy at the moment is on production subsidies. Not a lot of thought [has gone into] the demand side of the equation yet.” He continues, “We're starting to see the ramifications of that, with the biggest issue fuel quality. To realize biodiesel's maximum potential, we need a major step up in quality; we need a B20 quality spec.”

Right now, the only production spec in existence is for B100. The American Society for Testing and Materials (ASTM) recently upgraded that standard, adding new limits on calcium and magnesium to ensure that biodiesel blends of up to 20% will protect particulate traps for '07 engines, says Steve Howell, technical director at the National Biodiesel.

“Although this specification covers pure biodiesel, the majority of OEMs view the adoption of an ASTM blended fuel specification as a key component for universal acceptance of B20,” he emphasizes. “A subcommittee vote on an ASTM B20 specification will happen in December and, depending on the results, final approval for biodiesel blend specifications could come as early as the spring or summer of 2007.”

The industry still needs time to catch up to the existing standard, however. According to Jeff Probst, CEO for biodiesel maker Blue Sun, more than 60% of the biodiesel produced in the U.S. today does not meet minimum ASTM specifications. Even though both state and federal government incentives and mandates have helped more than triple the number of biodiesel production facilities over the past two years, many of them use unproven technologies that struggle to meet current ASTM standards, he points out.

Despite the challenges, however, biodiesel is here to stay. Perhaps its primary advantage is that the infrastructure necessary to deliver it to the marketplace is already in place. In addition, no changes to the vehicle are required. “You just drop it in and go,” says Arlington County's Hiller.


Many experts also believe there's sufficient cropland in the U.S. to produce biodiesel in large enough quantities to make it economically feasible. And government at all levels is encouraging the development of biodiesel through subsidies and tax incentives. “There are 117 pieces of legislation being considered right now by state and local governments to promote biodiesel,” Lysinger points out. “It's also a very practical fuel. It's fairly easy to set up a biodiesel production plant; a few million [dollars] will build you a good one.”

Research into developing biodiesel-specific crops, hardened against drought, is also taking off. For example, Blue Sun is working with new oilseed crops such as dry-land mustard, false flax, canola, and rapeseed varieties to reduce the cost of biodiesel feedstock by 40%. “This is crucial since the cost of feedstock, usually made from more expensive soybean oils, represents 75% of the total cost of biodiesel,” says Probst.

Blue Sun believes there is an estimated 5.6-million acres in wheat production in the arid high plains of Nebraska, Wyoming, Kansas and Colorado where they could add biodiesel plants in the crop rotation cycle.

The National Renewable Energy Laboratory estimates the total market potential of biodiesel using current technology and agricultural capacity to be 1.5-billion gallons. Taking full advantage of that could result in replacing 10% of current on-road U.S. diesel consumption.

“We're having a serious debate about energy policy in the U.S. so the timing is right for biodiesel,” adds DTF's Schaeffer. “Based on American grown crops, it makes a lot of sense. But we need to remember that…truckers are the ones who will get stuck with it if something goes wrong. And while biodiesel is not a silver bullet, it is one of many silver pellets we can use to address energy issues in our country.”

Get ready

To make the transition to biodiesel a smooth one, Ric Hiller, equipment chief for Arlington County, VA, suggests that fleets do the following:

  • Clean fuel storage tanks thoroughly before filling them with biodiesel. It's such a good cleanser that it will scrub off any deposits in the tank and carry them straight through to the pump — and into your trucks' fuel tanks.

  • Use 10-micron filters when transferring biodiesel from storage tanks to fuel pumps to make sure all deposits are removed.

  • Stock plenty of primary and secondary fuel filters for any equipment that will use biodiesel. The cleansing property of biodiesel means filters will become clogged more quickly.

  • Educate your drivers, equipment operators and technicians. Make sure they understand that if they notice any degradation in vehicle power, rough engine idling, etc., they should bring the vehicle into the shop immediately to replace the fuel filters. That will solve the problem 99.9% of the time.

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