Idle Free's Reefer-Based Electric APU Uses Truck's Reefer Unit to Power HVAC

Idle Free Systems' reefer-based version of its electric APU system allows drivers to use their reefer units to power HVAC systems.

The Idle Free electric APU is the only idle-elimination system on the market that meets all drivers’ needs – heat, air conditioning and hotel loads with a single system. But for fleets running refrigerated trailers, the benefits of the Idle Free electric APU can extend far beyond idle elimination.

The reefer-based version of the system uses patented Reefer Link technology to make energy from the reefer unit available to the drivers for unlimited run time of the air conditioner and heater, while also providing electricity for the drivers’ hotel needs.

The Idle Free electric APU is the most complete idle-elimination system on the market today. It is the only electric APU on the market capable of meeting heat, air conditioning and hotel needs without relying on the truck’s starter batteries, thereby eliminating the risk of the truck not starting. The Idle Free system is also an EPA SmartWay verified technology and California Air Resources Board (CARB) compliant.

The refrigeration units on the trailers used to transport perishable loads are powered by 50 hp diesel engines that are mounted to the front of the trailer. These reefer units have their own 12V electrical systems that are separate from the truck’s electrical system. When a truck is equipped with an Idle Free electric APU that includes the patented Reefer Link technology, it can be connected to the reefer unit’s electrical system to take advantage of the excess electric energy being created.

The Idle Free electric APU is unique for many reasons, but one of the most significant is that it runs on alternating current. Electric APUs that run on direct current suffer from lower efficiency, which translates to shorter APU battery life, less run time and, most problematic, the risk that the APU could jeopardize the truck’s ability to start. DC-based systems, due to their higher amperage draw for the air conditioner, rely on the truck’s starter batteries as an additional power source to run the APU. With those types of systems, you risk draining the truck’s starter batteries and therefore not being able to start the truck.

Idle Free’s AC-based electric APU, on the other hand, is a more efficient system, resulting in longer APU battery life and completely eliminating any need to use the truck’s starter batteries to power the APU. The AC-based system means the truck’s batteries will never be drained by the APU.

With Reefer Link, fleet owners are giving themselves one more way to power the Idle Free system.

“By connecting to a trailer’s reefer unit with the Reefer Link technology, we allow the APU’s batteries to be constantly charged by the reefer’s alternator,” says Robert Jordan, chief technical officer for Idle Free Systems, Inc. “This gives the driver yet another way to have unlimited runtime for the Idle Free APU.”

Reefer Link technology also gives drivers another very important benefit – it can provide backup alternator power for both the reefer unit and the truck in the event the alternator fails on one or the other.

Robert Hopton, chief executive officer for Idle Free Systems, says this gives both drivers and fleet owners peace of mind.

“For reefer fleets, failure of a TRU is high on the list of things that can cost time and money. A failure can mean thousands of dollars in lost revenue if the load spoils during transit or a delivery can't be made. For trucks equipped with an Idle Free electric APU with the patented Reefer Link technology, this concern is completely eliminated. And conversely, if something were to malfunction on the truck’s electrical system, Reefer Link allows the truck to use power from the functioning reefer unit to start the truck.”

Reefer Link is very easy to use and will not harm or interfere with the refrigeration function of the reefer, says Jordan.

“Reefer Link simply connects into the 12V power being generated by the reefer motor through a connection that looks like jumper cables. It will not harm nor cause excess wear on the reefer unit itself.”

The trailer connection is protected with a fuse and the connection from the truck and trailer is done with polarized connectors.

“This means they can only be connected one way,” says Jordan. “So the positive matches the positive and the negative matches the negative. There is no possibility that a driver could hook it up wrong.”

Trucks equipped with the Reefer Link system also have the option of purchasing an Idle Free electric APU without the AGM batteries. By eliminating this part of the APU system, fleet owners not only save on the initial cost of the system, but they further improve fuel efficiency by eliminating nearly 300 lbs. from the total  weight of the APU.

The option to eliminate the APU batteries is very cost effective for reefer fleets where all trailers can be equipped with the Reefer Link technology.