A Melton flatbed truck pulling a load of pipes

APUs & EPUs: What You Need to Know

Life on the road as a trucker comes with unique challenges, especially when it comes to maintaining the comforts of home while on the road. Over the road drivers need to keep their truck cool in the summer and warm in the winter, as well as have the power to run devices like a refrigerator, TV, microwave, or coffee maker. This requires the truck to supply a lot of power. Enter two essential pieces of technology that can solve the power problem: Auxiliary Power Units (APUs) and Electric Power Units (EPUs).

What’s the Difference Between an APU and an EPU?

Both APUs and EPUs are intended to reduce a truck’s idle time. When a truck is idling to maintain a comfortable temperature in the cab, a lot of excess fuel is burned, and unnecessary strain is put on the engine. While both of these units are key in providing additional comfort and reduced emissions, they do have some technical differences in how they operate.

Auxiliary Power Units are small engines that typically run off diesel fuel. This uses much less fuel than what would be required to idle your truck.

Electric Power Units (also referred to as electric APUs) consist of batteries operating an inverter. These batteries are charged by the tractor’s electrical system when it’s running. Since they are fully electric, they do not need diesel fuel to supply power.

What’s the Benefit of APUs and EPUs?

Where previously truckers had to turn their tractors on and off in order to turn on the AC or heater, APUs and EPUs step in to power appliances while the tractor is off. These units are best used during extreme temperatures (hot or cold), and at the end of the day while parked.

Some additional noted benefits include:

Enhanced Comfort: Truckers spend a considerable amount of time on the road, and have to make it a home away from home. Being able to run certain items while the truck is off is important for a sense of comfort, and even impacts the quality of sleep for drivers on the road. APUs and EPUs not only keep the cab at a comfortable temperature for sleeping, but are much quieter than running the main engine.

Reduced Emissions: EPUs are electrical units, which allow for zero-emission usage and are easily recharged while the truck is being used. APUs, while still producing some emissions, do not produce nearly the same amount as an idling tractor trailer engine. Both are much more environmentally friendly than idling the truck.

• Extended Engine Life: Excess idling can cause unnecessary damage to your truck’s engine. By utilizing your APU/EPU and reducing the amount of time a tractor trailer is spent idling, you can prolong your engine’s life and end up paying less for maintenance costs down the line.

• Fuel Savings: Idling tractors that run the main engine are going to consume diesel fuel to operate, and can end up consuming a considerable amount of fuel. While diesel APUs do consume fuel, the amount used in comparison is far less. If an entire fleet is operating with APUs or EPUs, the saved fuel costs can add up quickly.

What’s the Benefit of APUs and EPUs?

Melton Truck Lines has a fleet consisting of late model equipment, and our trucks are equipped with 1800 – 2000-Watt EPU Inverters. To learn more about the state-of-the-art features in our trucks, you can visit our equipment page here.

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