EVwire brief: Tesla has highlighted the Tesla Semi’s Electric Power Take-Off system, known as ePTO, on its Semi truck as a potentially significant advantage for commercial fleet operators.
The system allows the Semi to directly power refrigerated trailers and auxiliary equipment using electricity from the main battery pack. This eliminates the need for separate diesel-powered generator systems, which are commonly used in traditional trucking.
Tesla employees have highlighted that the feature means the Semi can potentially eliminate emissions not only from the truck's drivetrain itself, but also from the refrigeration systems attached to many freight trailers.
Tesla Semi Program lead Dan Priestley highlighted the feature in a short video:
Several members of the Tesla Semi team also highlighted the feature on LinkedIn:
Context:
Traditional refrigerated trucking units, commonly supplied by companies like Thermo King or Carrier, run independently from the truck and burn diesel fuel continuously to keep cargo cold.
Modern units typically consume between 0.4-1.1 gallons of diesel per hour, though older or poorly maintained equipment can burn significantly more, up to 3 gallons per hour or higher under demanding conditions.
They also tend to be noisy, maintenance-intensive, and increasingly targeted by emissions and anti-idling regulations. Thermo King addressed these regulations with a dedicated series designed for states with strict emissions standards.
Conventional refrigeration units are typically powered by diesel, such as this Thermo King S-Series
Tesla's ePTO system replaces that auxiliary diesel engine with direct electric power from the Semi's battery pack. Tesla notes that the system supports up to 25 kW of continuous output to power attached trailer equipment.
The setup also includes communication systems between the truck and trailer, along with safety mechanisms such as automatic disconnect protection if a trailer remains plugged in while the truck moves away.
The Tesla Semi’s ePTO system includes safety mechanisms, such as automatic disconnect protection
Tesla Semi's ePTO could transform refrigerated trucking economics
The Tesla Semi Long Range variant features a confirmed 822 kWh usable battery pack, as certified by the California Air Resources Board (CARB) in April 2026.
This means that the truck could theoretically provide more than 30 hours of continuous 25 kW output under maximum load conditions.
However, in real-world refrigerated transport, cooling systems cycle on and off rather than operating at maximum power continuously, potentially extending usable operating time further.
The Tesla Semi’s ePTO system could potentially provide 30 hours of continuous 25 kW output
The system could deliver several advantages simultaneously for logistics operators:
Reduced fuel costs by eliminating diesel consumption from trailer refrigeration units
Lower maintenance requirements from removing separate diesel engines
Near-silent operation at loading zones and truck stops
Reduced local emissions from both the truck and refrigeration equipment
Tesla has also hinted that the Semi’s ePTO system can support additional trailer and worksite equipment beyond refrigeration systems.
Source: Christian Reik on LinkedIn
DIG DEEPER into the Tesla industry news with our dedicated TESLAWIRE page. And don’t forget to subscribe to our EV industry newsletter to join 14,000+ EV geeks.
