Gel and back: Fleets make adjustments for winter biodiesel use

CHICAGO — Using B20 biodiesel in the Midwest winters might have caused diesel fleet and vehicle operators some concern years ago.

But that was then and this is now and both biodiesel and the technologies and testing connected to it have made strides that allow the renewable fuel to be more widely used in winter, including in cold, Midwest winters.

Peter Probst, co-founder and president of Indigenous Energy, a Chicago-based renewable energy consulting firm, has seen that use firsthand.

In addition to his work with Indigenous Energy, Probst manages the fuel for the Chicago Park District fleet of vehicles.

“That work has given me an opportunity to experiment with higher blends and we’ve had no issues,” he said.

The Chicago Park District fleet of vehicles, ranging from garbage trucks to flatbed trucks to diesel riding lawnmowers, has been using biodiesel, from a 40% blend in the summer and fall months, to a 20% blend in the winter.

Working with that fleet has allowed Probst to see how biodiesel and blends work in different applications.

“So far, we haven’t found any reason not to use the higher biodiesel blends and it’s been working out really well,” he said.

Probst knows it hasn’t always been the case with biodiesel.

“The biodiesel fuel quality today is a lot better than it was,” he said.

For Probst, the proof is in the pudding — or rather, samples submitted to the annual Biodiesel Technical Workshop, an event that gathers members of the biodiesel production industry and fuel consumers to talk about all things biodiesel.

The event includes testing and results for biodiesel samples submitted anonymously by biodiesel producers across the country.

“The fuel quality always exceeds the requirements for the standards. Ten years ago, you would have seen different types of fuel quality issues because the fuel wasn’t up to the specifications and also because the specifications themselves weren’t tight enough,” Probst said.

The industry itself has evolved its thinking to work toward fuel quality standards that both allow and encourage increased use of biodiesel in the winter.

The B20 Club is a collaboration between state soybean associations and the American Lung Association.

B20 Club members include green fleets that have been recognized for use of higher blends of biodiesel in their fleets. Members of the B20 Club include the City of Fort Wayne, Indiana.

Fort Wayne has been using biodiesel in its fleet for close to two decades and currently has almost 400 vehicles, including heavy equipment and vehicles, using biodiesel. Fort Wayne was recognized this year as a 2022 Leading Fleet by Government Fleet magazine.

Some of the quality improvements have come in the production process.

“A lot of companies distill their biodiesel as a final cleaning step. That filters out more impurities that can cause gelling issues,” Probst said.

For municipalities and municipal agencies, like the Chicago Park District, cost can be a prohibitive factor that can lead to fuel quality issues.

“Proper blending can be an issue. Many times, these municipalities have to go with the lowest bidder. If they are not using biodiesel that is up to proper specifications or if it is not mixed properly, that can cause issues in the winter,” Probst said.

One tool that can help diesel fleet and vehicle owners who want to continue to use a B20 biodiesel blend in the colder months is a cold-flow additive.

“The cold-flow additive counteracts any effects from the biodiesel’s lack of cold weather operability. The additives they are making now are so good and some of them are specialized for biodiesel blends,” Probst said.

He said that the rate for the additive is one gallon of additive per 1,000 gallons of fuel.

Another option involves equipment that can be installed on a diesel vehicle.

Optimus Technologies’ Vector System allows vehicles to run on B100, 100% biodiesel.

“You keep your original fuel system intact, so you start the vehicle on diesel. It adds an additional fuel tank for your biodiesel. As your vehicle starts on diesel, it warms up the engine and the heat exchangers,” Probst said.

“When it’s warm enough, it warms up the biodiesel tank and the system switches over to biodiesel after about 10 or 15 minutes. Then they can run biodiesel all the rest of the time because the system is heated.”

He said the system runs for a small amount of time after switching off the engine, to switch the engine back to diesel and to purge fuel lines with regular diesel, so the vehicle starts on diesel.

Probst has seen the use of the system firsthand, as seven of the park district’s vehicles use the Vector System.

For both diesel and biodiesel owners, Probst recommends having their fuel tested on a regular basis.

“We always recommend that people test it because testing, including testing regular diesel fuel, can find potential problems,” he said.