Prime Inc., Springfield, Mo., has its entire fleet equipped with auxiliary power units to limit idling, with an automatic 5-minute idle shutdown timer. But its tanker fleet was experiencing significantly higher idling, because product had to be kept heated to the right temperature.

"If you're carrying oils or chocolate, you have to keep it hot to keep it from congealing in the tanker." explains Nick Forte, fleet maintenance administrator. "Normally you idle the truck engine, it pumps water into the trailer from the radiator, circulates back to the engine. You have to idle the big engine to produce the heat and the power to pump that back to the trailer."

So Prime came up with an innovative solution using a Webasto heater designed for school buses. "We're using it to pump the coolant and heat the coolant without running the big engine. it's about a 0.7 per gallon an hour fuel savings," Forte says.

"I saw something similar a few years back but it was really complex. So I did some research online to come up with a viable solution that does what we need but is simpler. For the drivers there's just an on-/off switch."

After testing the solution on a few of its tankers, Prime is now rolling out the heaters to its entire tanker division of about 240 units. Although the fleet is primarily owner-operator, the company is classifying it as standard equipment as part of its lease purchase program.

"So far, the ones that have seen that it works are beating down my door trying to get them," Forte says. "In a typical night, you idle 11 hours, using 1.2 to 1.6 gallons per hour. If you're only burning at 0.4 [with this solution], you're saving a gallon an hour -- that's $44 per night at $4 for diesel fuel."


As for its APUs, Prime is using RigMaster. Forte says the company got new owners a few years ago, Mobile Thermo out of Toronto, which completely redesigned the product using premium components.

"Their LG200 is built to our spec and now they're marketing it. It's only 327 pounds; the others are closer to 500," Forte says.

"Everybody sees the RigMaster name and they associate it with the failed company, but it's whole new management, forward thinking," Forte says. "We've got probably 2,000 of their units now."

This unit fits easily under the bunk, Forte says, with a cooling capacity of 17,000 BTU.

For running in California, he says, "The great thing is, this unit is retrofittable -- there's a plug and play DPF. It's Tier 4 compliant."

The company doesn't have any problem getting its independent contractors to use APUs, he says, with a little education.

"We show that there is a direct correlation, if you reduce idle, that's money you keep in your pocket. We'll actually show the dollar expense to the operator, vs. giving it to the oil companies. Once you sit down and show them the numbers, generally it all kind of takes over."