By Terry Scruton
The word "biodiesel" is on the tips of many tongues these days. In some states, such as Minnesota, Washington and Colorado, the use of biodiesel is becoming a matter of public policy.
But what about engine manufacturers? With new ultra-low-sulfur-diesel regulations on the way and 2007 just around the corner, enginemakers would seem to have plenty on their plates already.
But they'd better make room for more, because biodiesel doesn't appear to be going away any time soon.
Most of the major truck engine manufacturers - Caterpillar, Cummins and Detroit Diesel - have policies in place regarding the use of biodiesel in their engines and are continuing research into the subject. But several areas of concern have already been identified.
To B20 or not to B20
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 recommends a blend of no higher than B5, and most manufacturers seem to agree.
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.
In its statement on biodiesel, Cummins states that it does not, at this time, recommend blends higher than 5 percent and will not until it completes evaluations on the other blends.
A spokeswoman for Cummins told Land Line that the company is still working on those evaluations and will modify its position once they are complete.
While Detroit Diesel agreed with Cummins on the B5 limit, Caterpillar, in its biodiesel standards, said it "neither approves nor prohibits the use of biodiesel fuels."
Unlike Cummins, Caterpillar said it "is not in a position to evaluate the many variations of biodiesel fuels and the long-term effects on performance, durability and emissions compliance of Caterpillar products."
Joe Suchecki, a spokesman for the Engine Manufacturers Association, said that even the B5 recommendation could change in light of what happened in Minnesota. Trucking operations in that state experienced fuel filter problems in late 2005 after a mandate went into effect requiring all diesel sold in the state to be a 2-percent biodiesel blend.
"That was really a surprise to us," he said. "But we understand that the fuel didn't meet quality specifications."
Minnesota officials concluded that the problems were isolated to a few specific batches of biodiesel and said they expected to put the 2-percent blend mandate back in effect Feb. 10.
Suchecki said quality specifications are something the engine manufacturers have been pushing for and insisting on from biodiesel producers. Currently there are no federal regulations when it comes to biodiesel quality assurance.
In addition to working with the National Biodiesel Board, Suchecki said the EMA is urging state and federal governments to insist that any subsidies or incentives provided to biodiesel producers come with a requirement to meet certain quality specifications.
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. Thus far, the standard is a voluntary one, though Minnesota is considering making BQ-9000 certification mandatory for biodiesel producers in the state.
Suchecki said it is also important that any fuel, biodiesel or otherwise, used in a truck engine meet the standards for diesel and biodiesel set up by the American Society for Testing and Materials.
The ASTM standards are used in the BQ-9000 accreditation, along with a quality systems program that includes standard practices for storage, sampling, testing, blending, shipping, distribution and fuel management.
Suchecki said that engine manufacturers 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.
"Any alternative fuel needs to meet the specifications and be of high quality or else you're going to have those problems," he said.
One big issue that Suchecki said has yet to be resolved, as far as the engine makers are concerned, is that of ultra-low-sulfur diesel.
"That's a long-term issue that hasn't been resolved yet," he said. "How biodiesel will (affect) engines and emissions once the ultra-low-sulfur diesel is used."
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.
Suchecki said that's all well and good, but the engine manufacturers are still taking a cautious approach, waiting to see what happens once ULSD is actually on the road, before making any further recommendations with regard to biodiesel.
"There (have) been a lot of comments on using biodiesel to increase the lubricity of ULSD," he said. "That's up to the fuel producers, if they want to use that. But whatever the fuel is, it's going to have to have the proper lubricity requirements whether it's biodiesel or another additive, so we're not really concerned about that."
2007 & beyond
Perhaps an even bigger issue facing biodiesel, in terms of engine performance, is the impact of the 2007 engine requirements from the Environmental Protection Agency.
According to the EPA rules, engine manufacturers are required to reduce on-highway emissions of particulate matter and nitrogen oxides by 90 percent. While Suchecki said the engine manufacturers are ready, this rule presents something of a problem for biodiesel.
Particulate matter may not be much of an issue, but one of the drawbacks to biodiesel is that it actually increases emissions of nitrogen oxides.
"In terms of 2007, using biodiesel by itself will not be sufficient to meet those emission requirements," Suchecki said. "We still need the particulate filters and we're getting close to when those are going to be produced."
Those new particulate filters in the 2007 engines pose another potential problem. Suchecki said the engine manufacturers are still testing and researching, but if the problems in Minnesota are any indication, biodiesel could still have a long road ahead.
Suchecki said in the long run, where engine manufacturers are concerned, biodiesel has both its advantages and disadvantages.
"We see a lot of value to the environmental benefits," he said. "But beyond that, there's really no added value or harm from it, so it's kind of a non-issue."