Adding an auxiliary power unit, or APU, to your truck can solve a lot of problems for you or your drivers. Once the APU has been installed there is no longer a need to idle for long periods of time or to stay at hotels during overnight trips. The APU provides you with a source of air conditioning, heating, and power for other appliances or electronics like televisions or microwaves. Along with providing this power source they also can end up saving you a significant amount of money when it comes to fuel expense.
When you idle a truck for a long period of time you end up burning between 0.75 to 1.25 gallons of diesel fuel per hour. As you can imagine, that can add up pretty quickly if you are idling for multiple hours per day five days a week every week. If you have a diesel APU installed you will see that fuel consumption shrink to a range of 0.10 to 0.50 gallons per hour. If we take the average number here between both scenarios we get 1.00 gallon per hour used when idling compared to 0.25 gallons per hour when using an APU. That is a seventy-five percent reduction in fuel usage.
All of this is assuming that you are using a diesel APU. There are also electric APUs out there that do not use any fuel. Instead these APUs rely on the stored power of batteries on you truck. This can give you one-hundred percent fuel savings, but there are a few downsides here with using an electric APU. Because electric APUs rely on your batteries they have a set amount of time they can run before the batteries are drained.
Even the most highly rated electric APU systems can only last between ten to eleven hours and that is with ideal conditions. If you are driving through the desert in Phoenix, Arizona in July then your truck’s electric APU will NOT last the full ten hours. The air conditioner will be constantly running in an effort to keep the truck cool. This constant running is going to drain the power faster then expected which will result in an overall shorter run time. The same can be said if you decide to run other appliances or electronics on your electric APU. The more you run the shorter the lifespan will be.
In conclusion folks a diesel APU will use anywhere between 0.10 to 0.50 gallons of diesel fuel per hour. Each APU is different so the exact number is going to depend on what brand and model that you have on your truck. There is also the electric APU option that does not use ANY diesel fuel… but they have set amount of time that they can run until the batteries are drained. You will then need to recharge the system for four to eight hours before you can start it up again.
I hope this article was helpful and able to answer your question,