The trucking industry is highly diversified and competitive. As a result, carriers and owner-operators are actively looking for ways to maximize operational efficiency, profitability, and service quality while controlling truck expenses, such as fuel, repairs, maintenance, insurance, taxes, and more. 

However, many truckers fail to account for one factor that notably contributes to their recurring fuel and maintenance costs: idling. Truck engine idling is the practice of keeping a freight vehicle’s engine running while not traveling.

Truck idling can occur during service activities on the road and when the vehicle is parked with no driver behind the wheel. According to the Office of Energy Efficiency, nearly 40% of freight vehicles idle for four hours daily on average due to traffic congestion, delivery stops, rest periods, and other reasons.  

As such, many truck manufacturers and carriers work tirelessly to reduce idling and restrict its financial impact on vehicles or operators through technology and effective operating strategies. 

In this article, we will explore the reasons why truck idling occurs and how it affects businesses. We will also dive deeper into the costs associated with idling and different strategies to reduce overall idling time. 

Why Does Truck Idling Occur?

Prior to implementing different solutions and strategies to reduce or minimize truck idling, it is vital to first understand why it happens. There are many reasons why a driver allows the engine to run while their truck isn’t moving.

Some may be reasonable, while others might be due to negligence and can be easily circumvented. For instance, idling could occur when a driver stops at a red light or warms their vehicle to its optimal temperature before commencing their journey.

Similarly, it could also occur when a driver decides to rest and freshen up at a truck stop while keeping the engine running as it is more comfortable or convenient. Below are the most common causes of truck idling: 

Driver Behavior

One of the key factors affecting idling time is a driver’s behavior during freight operations. For instance, depending on the route and shipment destination, many drivers keep their trucks running to mask noise, for personal safety, and remain comfortable during their breaks during or between trips. 

For instance, many choose to have air conditioning or heater running longer than it needs to in order to keep their cab and sleeper at their desired temperatures and conditions.

Such situations may arise before the start of a trip while the driver is getting ready, during a stop at the yard, or at a client’s premises when the driver is sorting out paperwork in the office.

Oftentimes drivers are inclined to take multiple trips or even opt for long-haul trips to increase their income. Hence, they require rest in-between trips and may not always want to incur additional expenses on a motel or other accommodation.

For that reason, truck drivers make use of built-in sleepers to take quick rests or spend the night during transit. During their rest periods, drivers would often keep their engines running to run or charge their electronic devices and keep their space warm or cool.

Finally, many trucks are equipped with appliances that require power, including portable refrigerators, coolers, TV, electric skillets, coffee maker, gaming consoles, WiFi, and more.

Most of these appliances are used when truck drivers aren’t on the move, especially during layovers. Therefore, these behaviors add to idling time and recurring fuel and maintenance costs. 

Operational Wait Time

Freight operations, especially those involving less-than-truckloads, often require the loading and unloading of cargo at multiple pickup and drop-off points during transit. Since the waiting window during stops is usually a few minutes, most truckers leave their engines running and continue their trip once the pickup or delivery is complete.

However, unforeseen circumstances such as a shortage of personnel or equipment may prolong the loading and unloading duration and significantly add to truck idling time.

Many trucks that are transporting perishable goods, such as meat, seafood, dairy products, and vegetables, in reefer trucks also need to maintain low-temperature levels through the refrigeration unit at all times during trips. 

Operational wait time could also be caused by other essential activities. For instance, drivers may need the signatures of clients for relevant shipping documentation once they’ve completed a delivery.

They may also need to talk to their supervisor or the next client on the delivery list to provide updates. While these individual activities can be performed quickly, over many trips and processes, it can easily add more minutes to the overall idling time. 

Weather & Road Conditions

Bad traffic is one of the major causes of idling during transit. Traffic can build up as a result of on-road accidents, bad weather, road constructions, obstacles, or poor traffic control.

Many cities and states experience heavy road traffic, especially during business opening and closing hours. Traffic congestion alone costs the trucking industry a hefty amount in fuel wastage, untimely issues, disrupted supply chains, and legal disputes. 

trucks idling in traffic
Trucks Idling in Traffic

Apart from being stuck in traffic, drivers spend a lot of time waiting at traffic lights during their trips. Although this wait time usually only lasts for a few minutes, it amounts to hundreds of gallons of fuel wasted every year per truck. 

Finally, inclement weather could also prompt drivers to keep their engines running, especially during the winter. Doing so serves several useful purposes. For example, it allows them to keep the fuel warm and avoid cold starting or other issues after short breaks or rests.

Moreover, it enables them to regulate temperatures within the cab while they wait for the weather to clear, or while they rest before getting back on the road again. 

How Does Truck Idling Affect Your Business?

Regardless of the cause, truck idling remains one of the most undesirable aspects of freight operations since it results in fuel wastage, increased wear and tear on components, as well as downtime.

Below are some of the ways it affects carriers and owner-operators:

  • Cost Implications – The biggest cost associated with idling is the cost of the fuel wasted during the idling period. Drivers waste hundreds of gallons of fuel every year, intentionally or unintentionally, forcing carriers to spend thousands of dollars more on fuel to haul cargo. Idling also has several indirect cost implications. For instance, the time consumed during idling unnecessarily could have been utilized to haul more cargo and generate more revenue. Moreover, carriers that pay drivers a fixed salary would see diminishing productivity. In other words, carriers pay a huge opportunity cost for every minute of idling. 
  • Truck Wear & Tear – When an engine idles, it doesn’t reach the optimal temperature to facilitate a complete combustion cycle. This can damage several essential parts of your truck’s engine, including spark plugs, cylinders, and exhaust systems. It also means that trucks need to be sent for repairs and maintenance more regularly.
  • Environmental Friendliness – Idling is an aspect of the freight industry that is detrimental to the environment as well as a carrier’s image as a business. As mentioned above, idling results in incomplete combustion, which can generate more dangerous greenhouse gases that escape into the atmosphere. Additionally, idling results in trucks consuming more fuel than required to complete a trip. The more fuel trucks consume, the more emissions they produce. According to the US Department of Energy, the trucking industry generates nearly 11 tons of carbon dioxide, 55,000 tons of nitrogen oxide, and 400 tons of particulate matter. Since truckers idle for four hours a day on average, minimal idling could reduce emissions by up to 16%. 
  • Safety Hazards – Idling can lead to several safety issues. For instance, when truckers leave their vehicles running with no one behind the wheel, they’re risking vehicle or cargo theft, acts of vandalism, or accidents due to unauthorized access. Moreover, sitting in an idling truck for a long time can result in respiratory problems for the drivers and others. 
  • Legal Implications – Finally, idling can lead to several legal implications, such as lawsuits and penalties. For instance, multiple US states, such as Arizona, California, Colorado, Hawaii, and Delaware, have made idling illegal due to safety, environmental, and health hazards. We will cover this topic in detail in the later section of this article.

How Much Does Truck Idling Cost?

According to the Argonne National Laboratory, rest-period idling alone in the US consumes nearly a billion gallons of fuel annually, costing carriers and owner-operators around $3 billion.

However, the cost of idling isn’t the same for every trucking company and depends on several factors, such as fuel consumption when idling, total or average idling time, repair costs, and more.

We have done extensive research on truck idling costs to help truckers and businesses understand the financial impact of this practice. The results are shown in the table below for reference:

Fuel Cost$4 – $5 per gallonBased on the average fuel in the United States
Fuel Consumption (Idle) 0.8 Gallons per hourBased on a publication from the United States Department of Energy
Average Idling Time 1,800 hours per yearBased on the Department of Energy’s publication and Argonne National Laboratory estimates
Maintenance$3,000 – $5,000 per yearBased on the average price for wear and tear parts and a publication from the American Trucking Association.
Total Idling Cost$8,160 – $11,200Based on the above values (average price per gallon x total truck idling time per year plus maintenance cost

The table above mentions the average idling cost of just one truck in a calendar year. Therefore, companies with a dedicated fleet of small and large freight vehicles could be paying hundreds of thousands or even millions of dollars for idling. 

Regulations On Truck Idling

According to the Environmental Protection Agency (EPA), more than half of US states have implemented strict regulations on truck idling to reduce greenhouse emissions and noise pollution.

Many governments are using idling laws and penalties to increase energy security while also reducing fuel imports. By reducing idling, they can reduce fuel demand, thus, reducing transportation energy costs. 

trucking idling management system
A Truck Idling Report from a Fleet Management System

As far as the fines go, different states have different punishments for drivers and their respective employers violating the idling laws. For instance, the state of New Jersey fines truckers $250 for their first idling violation offense.

Similarly, the state of California fines violating drivers $100 for each offense. On the other hand, the state of Pennsylvania warns first-time violators and fines them $100 and $500 for second and third offenses. 

However, there are some exemptions every driver or carrier should know about. These exemptions are listed by the EPA which can be found in the link that we have mentioned above.

One such exemption is that truckers are allowed to idle during loading and unloading processes or if they need to use their truck as a power source to operate power tools or equipment as part of their job.

For example, trucks transporting cement or sand need to operate hydraulic rams and lift gates to unload the cargo. Furthermore, one of the latest truck idling regulations is the designation of parks and stops where truckers can keep their engines running legally for a few minutes or longer.

By learning about these hotspots and adhering to their rules, drivers and trucking companies can avoid violations that could lead to hefty penalties.

How to Reduce Truck Idling Time?

Fortunately, there are many ways truckers can reduce idling time and save thousands of dollars on fuel and repairs every year. Below are two of the key areas in that every carrier can implement measures to significantly reduce their truck idling time.

Equipment & Technologies

With the influx of new technologies to improve operational efficiency and reduce trucking expenditure, carriers now have a wide range of methods to minimize truck idling costs.

Below is a table exhibiting a study done by the US Department of Energy on the return on investment (ROI) for some technological implementations:

TechnologyFuel Consumption (gal/hr)Cost of Equipment ($)ROI Timeline (yr)
Auxiliary Power Unit0.2 – 0.58,000 – 12,0003.6
Diesel-fired Heater0.04 – 0.08900 – 1,5000.6
Heat Recovery600<1
Storage Cooling0.158,500 – 8,8005
Automatic Engine Start/Stop0.251,500 – 2,5001
EPS (dual system)N/A<2,5001
Source: Adapted from US Department of Energy

From more fuel-efficient trucks to modern Electronic Logging Devices for real-time performance tracking, truckers have many solutions they can use to monitor and reduce their idling time.

  • Auto Shut Down – Many modern trucks are equipped with Automatic Engine Start/Stop (AESS) systems. Moreover, many older models have them installed separately. These idle management systems have a shutdown timer that prevents truckers from idling over a programmed period, usually a few minutes. They turn the engine on and off automatically to maintain sleeper-cab temperature and battery charge levels. However, AESS systems aren’t designed to eliminate idling. Instead, they’re used to reduce idling time and its consequences, such as emissions, extra fuel consumption, and engine damage. 
  • Cooling Technologies – Opting for storage air conditioners is a smart alternative to using a truck’s built-in air conditioner on hot days. For instance, an electric/battery-powered AC unit can drastically reduce idling time and help save even more fuel. You can also use portable or fixed solar panels during rest periods to power your cooling system and keep your cabin space cool while reducing your carbon footprint. 
  • Warming Technologies – Similarly, you can avoid using your truck’s built-in heater during the winter and opt for a portable DC heater that you can connect to your battery or a solar panel. Alternatively, you can install cab/bunk heaters that transfer heat to a coolant and circulate it across your cabin space. Since engines can remain warm for up to four hours after shut-off, this is an excellent alternative to idling since it utilizes heat recovery technology redirecting waste into a heat source. 
  • Auxiliary Power Units – Auxiliary Power Units (APUs) are designed to provide truckers with enough power to maintain climate control and run their essential electronic devices. However, most traditional APUs are still powered by fuel, albeit at lower consumption rates. Since truck engines are much larger and are used to power the entire vehicle, they are less energy efficient when powering smaller essential devices and appliances. Not to mention, modern APUs are more environmentally friendly in that they allow you to plug into a public power pedestal and use grid power to operate. 

Driver Behavior

Apart from leveraging innovative technologies, equipment, and solutions, you can also reduce idling time by employing different strategies to develop good driver practices.

For instance, many trucking companies provide idle reduction training to drivers to improve fuel efficiency by educating them about alternative solutions and best practices. Some go one step further by incentivizing drivers to minimize idling by offering the following.

  • Good Practice Rewards – Many trucking companies offer monetary rewards, such as bonuses, to drivers that comply with idling policies and regulations. Some companies also use recognition as a motivation tool for drivers who comply with company policies and regulations and consider these compliances in their appraisals. The trucking industry is highly competitive, therefore, a solid reputation for being environmentally friendly and cost-efficient can be used as an effective marketing tool to be the go-to choice for shippers and secure more loads. 
  • Awareness Programs – As mentioned earlier, idling leads to more greenhouse gas emissions. Hence, many companies use awareness programs to prompt drivers to play their role in saving the environment and improving energy security. Since these emissions are harmful, companies also use these programs to talk about how idling affects the environment, health, safety, and cost. These programs would typically be accompanied by guidelines on when trucks should be turned off instead of allowing them to idle.

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Andrew Lin

Co-Founder & Writer
at freightcourse

About the Author

Andrew is a multi-business owner with over 12 years of experience in the fields of logistics, trucking, manufacturing, operations, training, and education.

Being the co-founder of freightcourse has given him the ability to pursue his desire to educate others on manufacturing and supply chain topics.