The detachable electric drive unit fits between a truck’s tractor and trailer, allowing existing diesel vehicles to operate with electric assistance without requiring a full battery-electric replacement.

According to the company, the unit can propel a 36.3-tonne truck for more than 200 miles (322 kilometres) on a full charge while reducing carbon emissions by up to 85%. The company ultimately plans to establish a network of swap stations where drivers can exchange discharged dollies for fully charged units instead of waiting for conventional charging.

The dolly monitors the driver’s inputs and supplements the diesel engine with electric torque during acceleration. During braking, the electric motor switches to regenerative mode and recharges the battery.

“Our technology allows you to compete with diesel at cost, which is not true yet for other electric trucks in the US,” said Revoy CEO Peter Reinhardt.

He added that the company’s business model allows fleets to electrify existing vehicles without investing in entirely new trucks. That targets one of the biggest barriers to heavy-duty electrification in North America: the high purchase price of battery-electric trucks and the slow replacement cycle of these vehicles. Instead of requiring fleet operators to purchase new vehicles, Revoy owns the powered dollies while customers continue operating their existing diesel tractors.