Helping Drive Your Profits
Green APU maximizes profits by slashing fuel use and repair costs. More uptime, longer engine life, and less waste mean every mile driven adds dollars to your bottom line.
See how much you can save.
An auxiliary power unit designed to give truckers more comfort and flexibility on the road.
Designed & Assembled In the USA
More Flexibility Easier Maintenance
Green APU uses parts that are widely available at automotive stores, giving drivers and fleets total flexibility. Easy access to standard components means faster repairs, less downtime, and lower costs—keeping trucks running smoothly.
See how Green APU stands apart.
We’re With You For The Long Haul
Green APU has your back for the long haul with best-in-class warranty coverage and 24/7 support—delivering unmatched peace of mind, reliability, and protection mile after mile, year after year.
Why Green APU is Different
A Revolutionary Approach
Green APU continually refines its design for maximum reliability, manufacturing key components in-house and leveraging rigorous testing and research to deliver a product built to perform mile after mile.
Committed to Putting Drivers First
Family-owned and founded, Green APU was created to reimagine the APU with a smarter, more reliable solution that’s been putting drivers first since 2011.
Services & Support
Financing
Green APU offers flexible financing options, making it easier for drivers and fleets to invest in reliable performance.
Parts
We provide a wide selection of readily available parts for easier maintenance, and less downtime.
Service & Support
Green APU delivers dependable service and 24/7 support, keeping drivers and fleets running smoothly with expert help whenever and wherever it’s needed.
Frequently Asked Questions: Truck APUs
What is a truck APU and how does it work?
A truck APU (Auxiliary Power Unit) is a compact diesel engine mounted to a semi-truck's frame that independently powers the cab's heating, air conditioning, and 120V electrical systems without running the main engine. The Green APU Star Edition draws from the truck's own diesel supply and can maintain comfortable temperatures for 8+ hours on a fraction of a gallon of fuel, versus the 0.8-1.0 gallons per hour consumed by idling the main engine. This eliminates the need to idle at rest stops and reduces fuel costs, engine wear, and emissions significantly. The Green APU Star Edition uses a proven 3-cylinder Kubota engine supported by a nationwide dealer network.
How much does a semi-truck APU cost?
New diesel APUs typically run in the low to mid five figures installed. The Green APU Star Edition starts at $14,999 MSRP, and most owner-operators recover the cost in 12 to 18 months of avoided idle fuel, faster with heavy idle hours or high diesel prices. Green APU also offers financing so monthly payments are typically offset by monthly fuel savings. See the full cost breakdown, including financing and payback math, at greenapu.com/how-much-does-a-semi-truck-apu-cost/.
How much fuel does a truck APU save per year?
A diesel APU saves about 2,000 gallons of diesel per year for an owner-operator who idles 8 to 10 hours nightly, using the EPA SmartWay idle-reduction methodology (0.8 gal/hr main-engine idle rate). The Green APU Star Edition consumes roughly 0.1 to 0.2 gallons per hour for equivalent heating or cooling output. At current diesel prices around $4.00 per gallon, that translates to $5,000 to $8,000 in annual fuel savings. Use the Green APU savings calculator at greenapu.com/savings/ to estimate your specific annual return based on your fuel costs and driving pattern.
Does a truck APU work in extreme cold?
Yes. The Green APU Star Edition is tested and proven in extreme cold across North America, including Canadian winters and upper Midwest conditions. The Kubota diesel engine starts reliably in sub-zero temperatures, and the heating system maintains a comfortable sleeper cab temperature even when outside temperatures drop well below freezing. Green APU's 24/7 support team is available to walk drivers through cold-weather startup procedures and seasonal maintenance. Unlike battery-based electric APUs, a diesel APU's capacity is not diminished by cold temperatures.
Is the Green APU compliant with anti-idling laws?
Yes. The Green APU Star Edition is designed to keep drivers compliant with anti-idling regulations in more than 30 U.S. states and hundreds of municipalities. Most anti-idling laws specifically exempt commercial vehicles from idling restrictions when an approved APU is in use for cab heating and cooling. By running a Green APU, drivers avoid idling fines that can reach $250 to $1,000 per citation while maintaining full comfort. Green APU can provide compliance documentation to support interactions with state and local enforcement agencies.
Can I finance a truck APU?
Yes. Green APU offers flexible financing options for owner-operators and fleets, structured so that monthly payments are typically offset by monthly fuel savings from day one. Visit greenapu.com/financing-form/ to start the application process or call (877) 751-0686 to speak with a Green APU financing specialist. Many drivers find that the APU pays for itself through fuel savings in the first 12 to 18 months of operation.
Green APU is a family-owned manufacturer of diesel auxiliary power units (APUs) for semi-trucks, headquartered in Lemont, Illinois. Founded in 2011, Green APU designs and assembles the Green APU Star Edition in the United States. The Star Edition delivers 26,000 BTU of heating and cooling, is powered by a 3-cylinder Kubota diesel engine, features all-aluminum non-rusting construction and a single self-adjusting serpentine belt, and weighs approximately 350 pounds. The unit is engineered around standard automotive parts available at any automotive parts store nationwide, so it can be serviced by any qualified diesel mechanic without vendor lock-in. Green APU is an authorized partner with Fontaine Modification and operates a nationwide network of authorized installers and service centers. The product carries a 2-year, unlimited-hour warranty, backed by 24/7 USA-based technical support for the life of the unit, and most owner-operators reach payback in 12 to 18 months from fuel and engine-wear savings.