XL Fleet announced the market’s first plug-in hybrid electric (PHEV) Chevy Silverado 2500/3500 HD and GM 3500/4500 Chassis at the virtual 2021 Work Truck Show on March 8. The announcement adds further details to the company's November announcement of its intent to develop PHEVs for certain GM vehicles.

The battery packs are mounted completely underneath the chassis, a new configuration in line with XL’s next-gen battery pack, said Eric Foellmer, director of marketing for XL Fleet. The system, which weighs approximately 750 lbs., will be available for fleets by the summer of 2021.

Foellmer noted in the press conference that the plug-in system will result in a 50% mpg improvement and a 33% reduction in CO2 emissions compared to the traditionally fueled model.

The battery pack is larger than the one offered in the hybrid model and can be plugged in via the rear bumper plug port in the rear of the vehicle. Charging is compatible with any J1772 plug. Level 1 (wall outlet) would charge overnight; Level 2 takes roughly four hours for a full charge.

The system will be available on the 6.6L engine with the 4x4 driveline, on the 149-inch wheelbases or up, and it's available on double or crew cab options in any bed size. Fleets can opt for a bed delete for a completely configurable truck.

XL's plug-in hybrid-electric drive technology is now also available for GM 3500 and 4500 chassis configurations on 6.6L engines across all wheelbase types.

In the press conference, Foellmer also discussed XL Fleet's previously announced partnership with Curbtender, a provider of refuse trucks.

XL Fleet, which became publicly traded this year, will be co-developing an all-electric version of some of its most popular vehicles, as well as hybrid and plug-in hybrid versions. “It’s a great opportunity to electrify an industry with some of the most heavily polluting vehicles today,” Foellmer added.

Foellmer also shared the previously announced XL Grid division that will be rolled out over the next several months, allowing the deployment of large volumes of charging infrastructure.