Idling vehicle engines is costly for any fleet, and in more ways than one. Not only does engine idle inflict financial costs, but there is also a physical toll to pay for the continued running of the engine and its components. However, there are solutions available to assist fleets in combating engine idle and its residual effects. Engine idle reduction systems can extend the life of the engine, extend service intervals, and ultimately reduce a fleet’s costs.

Idling implications

There are many reasons a driver may leave the vehicle’s engine idling. Whether it be a stop at a delivery, a work truck at a job site, or a driver on their mandated rest period, the engine runs and various systems and components throughout the vehicle are powered. The reason for the idle aside, an idling engine brings costly ramifications. One of the most costly effects of engine idle is fuel consumption.

“The number-one thing for cost on [engine idle] is every hour that you idle a Class 8 tractor, you’re burning about a gallon of diesel fuel,” says Jim Flaherty, senior product manager at Thermo King, a manufacturer of transport temperature control systems, HVAC systems, and auxiliary idle reduction and temperature management systems. “That doesn’t sound too bad in the overall picture of things, but this could lead to 2,000 hours or even 3,000 hours of idling every year.”

Multiply that by the number of vehicles per fleet, and the fuel costs alone add up quickly.

Aside from fuel consumption, wear and tear on components is another consideration when idling vehicle engines.

“Engine wear and tear, alternator usage, belt [wear], and emission-related components like the DPF (diesel particulate filter),” are all impacted by engine idle, says Tom Stencil, senior regional manager, Eberspaecher Climate Control Systems U.S.A. Inc. The Eberspaecher Group is a system developer and supplier of exhaust technology, vehicle heaters, and bus air conditioning systems.

Engine aftertreatment systems can also be affected by engine idle.

“The other part that we consistently get feedback on, and it’s tough to put some hard numbers around it because every tractor system is different, but when an engine is idling the DPF systems on the tractors are not quite as good at burning off that particulate matter,” Flaherty says. “They may need to be burned off more often. We’ve actually heard from many fleets that they need to do a full cleaning more often when they see tractors that have really high idle percentages.”

Beyond vehicle systems and components, idling also has an impact on the environment since the vehicle is expelling exhaust into the atmosphere while running.

“We also know that idling engines cause emissions toward the environment,” says Kevin Aries, global product success lead, Verizon Connect. “And that, therefore, can impact the community that the businesses are operating in by producing emissions.” Verizon Connect provides connectivity and data insights to enable its customers to be more informed about vehicle and worker location, efficiency, safety, productivity, and compliance.

Not only are emissions released into the environment during engine idle, but there is also noise pollution to consider. With continually more strict mandates being introduced throughout North America that limit idle time, fleets will need to consider options to reduce engine idle in order to maintain compliance with such regulations.

Engine idle can also introduce issues surrounding engine oil.

“[Engine idling] also increases the risk of the engine oil temperature dropping below 100 degrees Celsius due to reduced engine loading,” says Darryl Purificati, OEM technical liaison, Petro-Canada Lubricants, a developer and producer of advanced lubricants, specialty fluids, and greases. “Idling can also cause an accumulation of water, the risk of acid formation, fuel dilution, as well as reducing the viscosity of the oil where it matters most in the lubrication zones. Together, these factors, along with other effects of idling, can accelerate the rate of engine wear and shorten oil drain intervals. For diesel-powered units, when excessive fuel dilution occurs, the volatility of the oil increases which can result in more soot finding its way into the diesel particulate filter. This has a negative effect on fuel economy as more regeneration cycles are needed to clean the DPF.”

Analyze idle impact

One way a fleet can determine whether or not the engine in question has suffered excessive wear due to idle is through oil analysis.

“The results of used oil analysis can indicate whether vital engine components have been compromised as a result of extensive engine idling, so being able to interpret the results is crucial for technicians,” Petro-Canada’s Purificati says.

Warning signs to observe in used oil analysis include fuel dilution as a result of unburnt fuel entering the crankcase. Increases in wear metals such as iron, aluminum, lead, tin, and/or copper are also indicative that engine components are wearing out. Purificati recommends fleets seek advice from lubricant professionals to pinpoint root causes of such wear to resolve the issue at hand.

Aside from reducing engine idle, fleets can mitigate component wear by utilizing properly specified engine oils to protect components facing excessive usage.

“Selecting the right lubricant requires careful consideration and due diligence,” Purificati says. “Before any steps are taken, the decision to select an engine oil should always begin with consulting the Original Equipment Manufacturer (OEM) vehicle manual. In addition, the OEM can also be contacted directly for specific advice when deciding upon a suitable product.”

With the proper engine oil selected and utilized, fleets can begin to prevent engine wear due to engine idle, and furthermore have the ability to reduce idle altogether.

“A lubricant with good low-temperature properties can reduce an engine’s need for idling in some climates, as they permit easier engine start-up and lubricant flow in low temperatures, which means the engine can be routinely shut off rather than being left idling,” Purificati says.

APUs and heaters

A major solution to engine idle reduction is transferring the power demands off the tractor engine to a separate power source in order to operate select systems and components throughout the vehicle. Auxiliary power units (APUs) can be specified onto tractors to power systems independently from the tractor engine.

“Carrier Transicold’s ComfortPro APU platform includes both diesel and electric models,” says Ryan Rubly, product manager, alternative power, truck/trailer/rail, Carrier Transicold. “With fully featured ComfortPro diesel APUs, a small engine runs a generator that provides power for cab air conditioning and heating, hotel power, and truck battery charging. The APU also provides truck engine pre-heating to avoid cold starts, and it offers optional shore power capability, enabling the system to be plugged into a 110/120-volt source when parked, bypassing the need to use the APU engine.” Carrier Transicold is an international producer of sustainable transport refrigeration systems for trucks, containers, and controlled atmosphere refrigerated transport.

Thermo King also offers both diesel and electric APUs through their TriPac product line.

“With an APU, we’re essentially putting on some type of power source,” Thermo King’s Flaherty says. “It’s a fully secondary system for cooling and heating for the tractor. We’re delivering power in a different way from the tractor engine and powering the HVAC. On the diesel systems, we obviously need to pull fuel from the truck’s system. And on electric systems, we’re utilizing the tractor batteries and of course adding additional batteries. Apart from that, the actual HVAC side of the system is completely independent from the tractor. This is true independent operation.”

Flaherty explains that the TriPac APU is ‘rightsizing’ power for the needs of the driver when the vehicle is stopped.

“The best way to think of it is we’re scaling the power delivery and power generation to only needing it for HVAC and battery recharging rather than having to move a 50-foot trailer down the road,” he says.

The smaller engine of an APU provides more efficient fuel consumption compared to the tractor engine when powering the same vehicle systems.

“When you’re idling that tractor, you’re burning one gallon of fuel per hour,” Flaherty says. “If you use our diesel [APU] product, you’re burning about 0.18 gallons per hour. So, we’re getting an 80 percent reduction in fuel consumption, but you’re still getting all the benefits that you need.”

To recharge batteries on the truck, the Thermo King TriPac APU utilizes a 120A alternator rather than the larger 240A or 300A alternator on the tractor engine, further contributing to the efficiency offered through an APU.

APUs are usually specified onto new vehicles and installed through dealer networks, although retrofitting APUs onto used vehicles is also an option.

“Typically, APUs are mounted on the side rail of the truck, so when spec’ing a new truck, it is important to allow enough room to accommodate an APU,” Rubly says. “Installation complexity will vary based on the type of system and options included. For example, installation of a basic electric APU air conditioning system can be done in significantly less time than a fully featured diesel-powered APU, or even an electric APU with options such as a fuel-fired heater and an inverter for hotel power.”

One determination a fleet will need to make when deciding to specify an APU is whether to utilize an electric APU or a diesel APU. Currently, the industry predominantly specifies diesel APUs over electric. This is largely due to the fact that diesel APUs have been available for a longer period of time and are therefore more thoroughly proven, Flaherty says. Both Thermo King and Carrier Transicold offer cost calculators on their respective websites for fleets to evaluate the cost savings offered through implementing an APU into the fleet.

The major differences between diesel and electric APUs revolve around runtime, cooling power, and emissions/fuel consumption.

“With diesel, you have unlimited runtime and more powerful cooling,” Flaherty says. “And with electric, you’re going to have a finite amount of battery and slightly less cooling power. You can always get more power by adding more batteries, but the fact is [the batteries] weigh a ton, [and] fleets don’t want to add more weight.”

Depending on the electric APU model, typical runtimes on a full charge range between seven and 11 hours, whereas with a diesel APU, average runtime is only limited by the amount of fuel in the tank.

“Battery-powered APUs provide a lower cost entry point, and their simpler configuration means less maintenance than systems driven by a diesel motor,” Rubly says.

As mentioned before, diesel APUs significantly reduce fuel consumption and emissions. However, electric APUs reduce those factors even further, and also produce less noise pollution.

Maintenance requirements for diesel APUs are similar to that of any engine maintenance requirements. This will include changing the oil and oil filter, replacing the air filter, changing the fuel filter, as well as inspecting hoses and connection points.

Electric APUs require a different set of priorities when it comes to maintenance, particularly the battery system, its connection points, and the replacement of batteries. With advancements in the technologies of APUs, service intervals have increased to around 2,000 hours of runtime for both diesel and electric APUs. Integrating APU service intervals into a fleet’s PM schedule is crucial to maintain the performance of the APUs, as well as capturing the most out of the benefits offered through their performance.

Similar to APUs, Eberspaecher offers air and water heaters through their Airtronic and Hydronic product lines, respectively. These products are designed to provide in-cab and engine temperature control while limiting the consumption of the vehicle’s diesel fuel. The air heater operates through the use of a small amount of fuel from the truck’s fuel tank, as well as some battery voltage to start the unit. An internal combustion-air fan motor and fuel metering pump deliver fuel to an atomizer screen. With the heat exchanger ignited, the combustion air fan moves air through the heat exchanger and provides heat to the truck’s cab. The Airtronic heater operates without the truck’s engine running, offering climate control without an idling engine.

Stencil mentions that maintenance procedures and service intervals for the air heaters are straightforward.

“You do not have to remove the heater from the bunk to do the maintenance on an Eberspaecher Airtronic air heater,” he says. “The items that will be replaced will be the atomizer screen and the fuel filter, which is internal to the fuel metering pump. When servicing an Eberspaecher heater, you can visit our webpage where we have an extensive library of videos that show how to do maintenance procedures.”

A maintenance recommendation Stencil offers is that fleets run the heater for at least 15 minutes per month, every month of the year.

“This keeps the fuel system primed, keeps the internal parts of the fuel metering pump from varnishing up by cycling out stale fuel, it helps burn off any accumulated carbon in the combustion chamber, and most importantly, the heater will work when you need it,” he says.

Eberspaecher Hydronic water heaters provide another option for fleets looking to reduce engine idle.

“This is one of the areas that are overlooked when adding equipment to a truck, or any piece of equipment you may have, such as skid steers, day cabs, trailer spotting units, or remote equipment that does not have an electrical plug available for an engine mounted block heater,” Eberspaecher’s Stencil says. “Consider it a portable block heater that circulates hot coolant throughout the engine. It is mounted on the truck or equipment and stays with it wherever it goes, so no more electrical plug-ins or cords to worry about. Simply set the timer for a couple of hours before departure and you will have a warm engine before you start your day.”

Stencil further notes the company has focused on increasing dependability of the water heaters by including a brushless motor, moving electronics away from internal heat sources, and creating a combustion process that requires less maintenance.

Monitoring idle

Another method of combating engine idle is through monitoring engine and driver behavior through tracking software. Verizon Connect offers their GPS Fleet Tracking Software, which can be used to gather data surrounding what vehicles and drivers are actually doing with their vehicles so fleet managers can then improve the performance of how those drivers are operating their vehicles and ultimately decrease the time spent idling.

“Verizon Connect Solutions helps provide visibility where vehicles are and how they are operating, it helps fleet operators monitor driver safety and behavior, and it allows them ultimately to increase the efficiency and productivity of their workers and drivers, and [offers] the ability to ensure they are operating in a safe manner,” Verizon Connect’s Aries says.

This is done through vehicle tracking and obtaining data from the vehicle and its systems. That data is then surfaced visually and in an easy-to-interpret way for a fleet owner, manager, or dispatcher who is operating those vehicles from an administrative perspective.

Verizon Connect’s GPS Fleet Tracking Software allows a fleet to look at how long an engine has been idling and receive alerts when it has been idling longer than a predetermined amount of time. Should an engine surpass this parameter, an alert will be sent to the fleet manager and/or the driver via their mobile device or via email. This allows the driver to correct the problem in the moment. Fleet managers can also take a more holistic approach by running reports and viewing data over a period of time that would reveal trends, providing information around how long drivers tend to idle their vehicles.

Not only is the amount of engine idle time customizable for the fleet, but there are other options available to monitor engine idle and alert in case of parameter breaches.

“You can create exceptions for different scenarios,” Aries says. “We know that depending on the vehicle or what job is being performed, some vehicles may need to be in an idling state to perform a certain function. For example, a cement truck will need to be in an idling state for that engine to power some of the mechanical components of that vehicle. With GPS Fleet Tracking Software, you are able to distinguish what makes sense for your fleet. You would be able to define when it is appropriate to idle at a certain jobsite by defining a geo-location through a geo-fence, defining a certain area where it would be appropriate to have an idling engine.

“You can also, through the way we can connect to a vehicle’s engine, detect when one of those functional components is turned on,” he continues. “So, you can create an exception when one of those components is activated. With a cement truck, if you’ve got a mechanical component dispatching cement out of the back of the truck, we can view that as an exception to idling [and bypass sending an alert].”

Alert parameters can be set for individual vehicles in the fleet, a group of vehicles in the fleet, or across the entire fleet. The customization options are limitless as to what would constitute alerting excessive idle.

Fleets have two Verizon Connect GPS Fleet Tracking Software hardware installation options. One is a self-installation method in which a piece of hardware is installed by connecting to a vehicle’s OBD-II port. The other option is professional installation. To obtain information from the engine, particularly idling information, Aries recommends fleets utilize the professional installation method. The hardware to be installed covers “everything under the sun,” Aries says, from heavy duty Class 8 vehicles to medium duty vehicles, as well as consumer vehicles used in a commercial capacity.

“Anyone with a vehicle tracking or telematics solution will essentially be seeing less maintenance on their vehicles over time,” Aries says. “Being able to monitor vehicles, how they are driving, the safety of those vehicles, reducing idle time and engine usage which cause wear and tear results in less time with the mechanic given that you are able to have better visibility of how long those vehicles have been running and what they need and when [they need it].”

The GPS Fleet Tracking Software provides insight and intelligence to a fleet, providing data needed to train and coach drivers in a way that will help reduce the amount of time engines are spent idling.

“This data is an opportunity for fleet managers to have better conversations and interact with their drivers so that they can work together and create a culture around better driving behavior and more sensible idling and driving practices,” Aries concludes.

Conclusion

Engine idle has its consequences. Costs arise through additional fuel consumption, wear and tear of components, higher runtimes, emissions and noise pollution, and inefficiencies in operations.

However, there are a range of solutions available for fleets to implement into their operations in order to reduce engine idle and combat the ramifications of idle. Proper engine oils will maintain lubrication and aid in preventing wear and tear; APUs and heaters will move power demand from the tractor engine to auxiliary power to mitigate idle times; and tracking software can help a fleet monitor engine performance and instill driver behaviors that reduce idling.

Whichever solution a fleet determines fits their model of business, the result will be increased efficiency and cost savings.