A second diesel engine
A small extra engine bolted to the truck. It still burns diesel to make heat and electricity.
- Still burns diesel
- Audible mechanical noise
- Requires periodic maintenance
- No regulatory compliance benefit
- No CO₂ reduction
Us vs Them
Same job.
Different numbers.
To keep the cab warm or cool overnight, truckers usually do one of three things: run a small second diesel engine, install a generic battery box, or fit a Cabin Comfort. We did the math — here’s the honest comparison.
Diesel saved / year / truck
2,921 gal
CO₂ avoided / year
65,526 lb
Monthly fuel savings
$750–$1k
Engine connection required
None
Three approaches, three outcomes
Diesel-burning box vs. generic battery box vs.
Cabin Comfort.
A generic battery system
Runs off batteries, but the batteries are charged from the truck’s alternator — so the engine still has to run periodically.
- Some fuel savings
- Periodic battery maintenance
- Requires engine/alternator connection
- Limited remote diagnostics
- Comfort varies by model
A dedicated battery climate unit
Self-contained battery + climate system. Charges itself while you drive. The diesel engine never has to run just to keep you comfortable.
- Saves 1 gal/hr · $750–$1k/mo
- Silent operation
- Maintenance-free
- No engine / alternator connection
- Remote monitoring app
- Helps meet idle-time regulations
Detailed comparison
The full
side-by-side.
| Spec | Diesel-burning unit | Generic battery unit | Cabin Comfort |
|---|---|---|---|
| Fuel savings vs. idling | ~ 0 gal | Partial | 2,921 gal / yr |
| CO₂ reduction | None | Partial | 65,526 lb / yr |
| Noise level | Audible (small engine) | Low | Silent |
| Maintenance | Oil, filters, belts | Battery service | Maintenance-free |
| Install time | Days · certified shop | Most: 1+ day | ~ 2 hours |
| Engine / alternator connection | Required | Required | Not required |
| Driver comfort | OK · noise issue | Varies | Home-like comfort |
| Remote monitoring | No | Varies by model | Proprietary app |
| Idle-rule compliance (CA 5-min) | No benefit | Partial | Yes |
| US federal rules (DOT, EPA, FMCSA, NHTSA) | No support | No support | Supports compliance |
| Field-tested | — | — | 6 years extreme conditions |
Ready to switch sides?