Ten years ago, we would have predicted that by now no truck would be idling anywhere in the United States,” says Mike Roeth, executive director of the North American Council for Freight Efficiency, which studies fuel-efficiency tactics and technologies. Yet despite widespread anti-idling laws and lots of available idle-reduction technology, go to any truck stop today and you’ll see plenty of trucks still idling.
Even in California, which has the strictest emissions regulations in the country, new trucks with advanced emissions control systems can be certified as “Clean Idle.” And right now, diesel prices are low enough that for some truck owners, it’s just not a priority — or at least not as high a one as keeping drivers comfortable and happy in the face of an ever-worsening driver shortage.
Yet even with lower fuel prices, there’s still plenty of money to be saved by reducing idling. A 2016 report by Argonne National Laboratory found that all idle reduction options save money when fuel costs more than $2 per gallon. Harder to quantify but just as real is the saved wear and tear on the truck engine.
Taylor White, vice president for 235-truck dry van fleet Alabama Motor Express, says his company adopted APUs over a decade ago. The fleet has tried both diesel and battery-powered versions, but currently has Thermo King’s TriPac diesel APU on all its trucks. “When fuel got to its peak we would see a return [on our investment] in 18 months just on fuel numbers,” he says.
While lower diesel prices mean the ROI isn’t as fast, he says, using APUs has improved trade-in values. With the hours on the truck engine significantly reduced, AMX has been able to increase service intervals and is getting more money for its trades, because buyers know the engine doesn’t have as much wear and tear on it.
“We operate under a three-year trade cycle, and we feel like we see our return on investment very easily within those three years,” White says.
Helping drivers keep their cool
Drivers like some idle reduction technologies and strategies more than others, Roeth notes. “It comes down to, this cab needs to be as home-like as possible.” That means refrigerators, microwave ovens, TVs, computers, and of course staying warm in the winter and cool in the summer. Drivers with sleep apnea need to be able to power CPAP machines to treat their condition. All of that’s a big challenge when you’re trying to reduce idling.
And that’s why idle reduction goes beyond picking the technology that can reduce idling the most. Driver buy-in and education is vital.
At Alabama Motor Express, White says, “We’ve got a fuel bonus, and idling is a part of that fuel bonus. In my opinion, it’s one of the top issues when we’re looking at our fleet’s fuel mileage. Education is so important, because a lot of times, it’s like a light goes off in their head,” when drivers realize just how much fuel is wasted idling. “You show them some numbers, be very transparent – they get it.”
Jane Jazrawy, co-founder, president and CEO of CarriersEdge, which does online driver training, says they’ve found it’s more effective to work idle reduction training, along with fuel efficiency training in general, into other lessons.
“You don’t just throw training at someone in isolation,” she explains. “You have to provide that training in a bigger context.”
Benchmarking is another key factor, she says. But you need to not only let drivers see how their performance stacks up to their peers, but also provide coaching if they need to improve. “We find it’s not all about just training people and saying, ‘You must do this,’ but having a constant conversation with people in order to change their behavior and encourage them to keep it changed.”
John Pope, chairman of Cargo Transporters in Claremont, North Carolina, says to help reduce idling, “you have to have almost immediate access to the data and have an action plan that you stick to in order to keep it in check. Clearly drivers don’t idle to intentionally waste resources. It’s generally old habit that comes from years of being in equipment where there was no other alternative.”
Like other fleets, idle time is one of the parameters Cargo Transporters tracks with a driver scorecard.
Making idle reduction efforts more difficult, Roeth says, is that there’s no single, easy answer for the best way to reduce idling. “Less expensive, smaller things could take a fleet from 40 or 45% idling down to 25%,” Roeth notes. To get down to 5% or 10% takes more expensive options, which have their downsides.
Following are highlights of the pros and cons of various types of idle reduction solutions.
Using the engine electronics
Electronic engine parameters can be set to limit the amount of idling. These will shut down the engine after a specified time or based on ambient air temperature. There’s no extra cost for this option, but depending on the temperatures you set, drivers may not be able to sleep comfortably. You may think they should be perfectly comfortable with their windows open on a 75-degree night, but some drivers are concerned about safety or outside noise, Roeth points out. No surprise, then, that drivers have been known to find ways to re-set the parameters. But many fleets use idle shutdown parameters in conjunction with other idle reduction technologies.
Automatic engine start/stop systems turn the main engine on and off as needed for heating and cooling when the driver is resting, also warming the engine and charging the batteries. These systems don’t completely remove the need for idling, although if they are used with an engine that’s Clean Idle certified, the truck can idle without violating idling regulations. One downside is that the starting and stopping of the main engine can disrupt drivers’ sleep.
Auxiliary power units
APUs provide on-board power for climate control and drivers’ electrical devices. Traditionally APUs were powered by small diesel engines, but in recent years, battery-powered APUs and even APUs powered by alternative fuels such as natural gas have become available. Some APUs also are equipped to plug into a power
pedestal at a truckstop or fleet terminal for grid power.
Drivers like diesel APUs, says Roeth. “You can park anywhere and turn that generator on and have what you need. It’s powerful, so if you like sleeping with pajamas and a blanket on a 95-degree day, you can do it.”
Drawbacks may include weight (although most states have weight exemptions), higher upfront cost than other options, and the fact that you are still using some fuel. Many fleets have had maintenance problems. In California, diesel APUs on newer trucks must have their own diesel particulate filter.
Adding an inverter to power the HVAC system lowers the amount of fuel used by the diesel APU, notes NACFE. Adding a fuel-operated air heater on top of the inverter would use the least amount of fuel.
Battery-powered APUs offer heating, ventilation and air conditioning while parked. They are powered by a separate set of batteries, and some can connect to a shore power source, or even a reefer unit in the case of the Idle Free system from Phillips & Temro. With few moving parts, they cost less to maintain than diesel APUs — but the batteries eventually will need to be replaced. These systems are quiet and produce no emissions, but they may not provide enough cooling capacity for long rest periods or when operating in very hot temperatures. Some fleets also note they don’t provide enough power for drivers to use CPAP devices all night long.
Tactics to help overcome the shortcomings, NACFE says, are to add an automatic start/stop system to charge the battery, or to use with off-board AC power/truck stop electrification. Some fleets and suppliers are using solar panels to help make up the difference between stored battery power and overnight comfort needs.
Cargo Transporters uses a battery HVAC system from Dometic, as well as shore power if there is access; there are 21 parking spots at its Claremont terminal where drivers can plug in. While there’s a five-minute idle shutdown programmed on the engines, Pope says, “We do have the engine ECM set to allow idling if the temps get out of an acceptable range for the aux unit to keep up.”
Tennessee-based Cooper Freight uses Freightliner ParkSmart battery HVAC units. Over the past seven years the fleet has dropped its idle time from 55% to 9%. General Manager Mark Cooper says the units don’t have a problem providing enough power for the full rest period, unless “it exceeds eight hours and the outside temp is high. If the unit should cut off, drivers are instructed to allow the truck to run for two hours only… This will give them an additional eight hours” of cooling.
Bunk heaters and thermal cooling
Diesel-fired heaters, such as those from Eberspacher or Webasto, are inexpensive to purchase and maintain, says NACFE. Argonne National Laboratory found that bunk heat, whether diesel or plug-in, almost always was the most cost-effective way to provide heat, even if the truck is equipped with an APU. However, they don’t address cooling or electrical power requirements.
Thermal storage systems, such as Webasto’s BlueCool, capture cooling while the truck is in motion that can be used to cool the sleeper when the truck is parked. Thermal energy is stored in a frozen graphite/water matrix. An electric refrigeration compressor freezes the water when the truck is running. When the engine is off, fans draw in warm bunk air, which is cooled by the frozen core, then blown back into the sleeper. While quiet and not requiring extra fuel or batteries, these systems only provide cab cooling, not heating or AC electrical power, and the amount of cooling time is limited.
AC power ports make it possible to provide electricity for block heaters, to provide AC power using an inverter/charger, or to run the heater or air conditioning of a diesel APU or battery HVAC system. Shorepower Technologies offers truckstop electrification at more than 1,800 parking spots at 62 U.S. locations. Most truck makers offer power ports as an option, but a lack of infrastructure at truckstops has prevented widespread adoption.
Combining truck stop electrification with a fuel-operated air heater and an inverter/battery charger is a good option for some fleets, notes NACFE. However, this combination does not provide a way to cool the cab when there is no power available
Some truck stop electrification systems, such as Idle Air, not only bring 120V AC power to trucks but also provide heating and cooling through a hose inserted into an adapter in the driver’s side window.
Some fleets are installing shore power outlets at their own facilities. Idle Air, which has approximately 40 truck stop locations, is increasing its efforts to install the infrastructure at fleets. Currently, Idle Air has eight such terminal facilities in operation and expects to reach about 15 by the end of the year.