Beginning in June Peterbilt will make its ComfortClass environmental control system available on 63-in. sleeper models. Presently, it’s an option only on 70-in. Unibilt sleepers.

Introduced last year, the system uses a combination of batteries, a diesel-fired heater, and thermal storage to provide a temperature-controlled environment for parked drivers without idling the engine. It also offers 110-volt electrical service to run computers, microwaves, and other electronic devices in the sleeper. It can use shore power when plug-in services are available.

While the vehicle is in operation, a 185-amp alternator charges the power pack (four dedicated, advanced-glass-mat, deep-cycle batteries) and starting batteries. At the same time, the electric AC compressor charges the thermal storage unit mounted behind the sleeper.

Peterbilt claims the ComfortClass system can maintain comfortable temperatures inside the cab for up to 10 hours with ambient temperatures as high as 95 degrees. It has the potential to reduce annual fuel consumption by approximately 8%, the company says, resulting in a reduction of operating expenses by as much as $5000 a year, per vehicle.