Tesla Announces Specs for the Tesla Semi

For years, the most common critique of the Tesla Semi was not about range or its center-seat cockpit, but a logistics concern: electric trucks are heavy.

Many skeptics and legacy manufacturers argued that to reach a 500-mile range, a Class 8 electric truck would need a battery so large that it would significantly reduce payload, making it less economical than diesel alternatives.

With an update to the Tesla Semi website, Tesla states it has addressed both range and weight. Final production specifications, including curb weight, are now published ahead of the first major customer delivery expected later this year.

Tesla Semi Specs

The table below lists the official specifications for the Standard Range and Long Range variants.

* - ePTO is the Electric Power Take Off, which can run trailer functions like refrigeration.

The Magic Numbers

In trucking, every additional pound of curb weight reduces payload by the same amount. A traditional diesel day cab typically weighs between 15,000 and 18,000 pounds. Many expected a comparable electric truck to struggle to stay under 30,000 pounds. Tesla’s final production figures are notably lower: the Standard Range model, with ~325 mi of loaded range at 82,000 lbs gross combination weight (GCW), has a curb weight of less than 20,000 lbs. The Long Range model, delivering ~500 mi of loaded range at 82,000 lbs GCW, lists a curb weight of 23,000 lbs.

Accounting for the additional 2,000 lb allowance granted to ZEV Class-8 trucks in the US and Canada, the payload gap versus a diesel rig effectively disappears. The latest battery packs achieve high energy density at low weight, surpassing prior industry expectations.

Comparing the Semi to a Model 3

Tesla cites energy consumption of 1.7 kWh/mi while loaded at 82,000 GCW. For context, a Model 3 is about 20x lighter (4,000 lbs) and uses roughly 0.25 kWh/mi, or about 1/7th of the Semi’s energy use.

Earlier prototypes and competitor figures often hovered around 2.0 kWh per mile for the Semi. Hitting 1.7 kWh/mi at full load reduces the battery capacity needed to achieve 500 miles. Smaller batteries cut weight, which increases potential cargo.

Powertrain & Charging

The updated specifications indicate up to 800 kW of drive power, which translates to over 1,000 horsepower with EV-style instantaneous torque. This enables maintaining highway speeds even on steep grades, a situation where heavily loaded diesel trucks can slow to about 30 mph.

An ePTO (Electric Power Take Off) rated up to 25 kW can power trailer equipment such as refrigerated units directly from the main battery, removing the need for separate diesel generators and reducing complexity and emissions.

Both trims support a peak charging rate of 1.2 MW (1,200kW). For comparison, the Cybertruck charges at 500kW. Being able to recover 60% of range in roughly 30 minutes aligns with a driver’s rest break, minimizing downtime and giving the Semi an effective daily range comparable to a diesel semi.

Designed for Autonomy

Both variants are designed for autonomy. Tesla Semis have been seen with LiDAR test equipment, suggesting an eventual introduction of FSD for the Semi, although it has not been a priority.

Looking ahead, Unsupervised FSD could move cargo between points across North America. In the near term, broader customer deliveries are anticipated later this year.