Revoy's Swappable Electric Dolly Converts Diesel Semis into Hybrids

Key Takeaways

• Revoy’s swappable electric trailer can convert diesel semis into hybrids.
• The 575 kWh plug-in module can cut emissions by 85%.
• It is available to fleet operators with a per-mile subscription model.
• The dolly can be swapped in under five minutes at highway hubs.
• Revoy aims to scale production and have dozens of second-gen units running US shipping routes by late 2027.

How Does the Swappable Electric Dolly Work?

The product is a self-powered unit that connects directly between the tractor’s fifth-wheel hitch and the cargo trailer.

The electric add-on measures 13 feet long and tips the scales at 22,000 lbs, with a 575 kWh lithium-iron-phosphate battery that feeds an electrically driven axle.

When the truck driver hits the throttle, the system reads the load demand and engages the electric motor to shoulder the heavy lifting, keeping the diesel engine from straining.

What are the Benefits in Fuel Economy and Emissions?

With the add-on fitted, a standard semi hauling an 80,000 lbs gross vehicle weight can cover more than 200 to 250 miles on electric power alone.

The company says average fuel economy on the diesel hybrid can climb from 6 to 8 mpg to 20 to 35 mpg, and touch 40 mpg on short-haul runs under 150 miles.

Carbon emissions drop by as much as 85%.

How Does the Swapping Process Work?

Rather than parking a rig for hours to charge the enormous battery, Revoy built the dolly to be swapped.

The company is putting together a network of highway hubs where a truck can trade a drained unit for a fresh one, with the whole exchange wrapping up in under five minutes.

What is the Business Model for the Swappable Electric Dolly?

Instead of selling the hardware outright, Revoy hands the electric dolly to fleet operators as a service with a subscription fee.

The company secured regulatory approval from the National Highway Traffic Safety Administration in 2023, then wrapped a yearlong pilot with freight company Ryder System Inc. in 2024.

What are the Future Plans for Revoy?

Revoy raised $27 million in its latest funding round, pushing total funding to $41 million.

The company is developing a cheaper second-generation dolly that pairs a smaller battery with the same 200-mile EV range.

The plan is to scale production and have dozens of second-gen units running US shipping routes by late 2027.

Frequently Asked Questions

Q: How does the swappable electric dolly work?

The dolly is a self-powered unit that connects between the tractor’s fifth-wheel hitch and the cargo trailer, with a 575 kWh lithium-iron-phosphate battery that feeds an electrically driven axle.

Q: What are the benefits of the swappable electric dolly?

The dolly can cut emissions by 85% and fuel use, and can cover more than 200 to 250 miles on electric power alone.

Q: How does the swapping process work?

The company is putting together a network of highway hubs where a truck can trade a drained unit for a fresh one, with the whole exchange wrapping up in under five minutes.