The ZX5 is a battery-electric, low-floor transit bus, originally released by Phoenix Motorcars (at the time Proterra) in 2020.
Since 2024 it has been manufactured by Phoenix Motorcars at a plant on Whitlee Court in Greenville, South Carolina.
On September 15, 2020, Proterra announced the ZX5 available in lengths as a replacement for the Proterra Catalyst. The Edmonton Transit System in Edmonton, Alberta was the launch customer for the 40-foot ZX5.
The ZX5 is built out of the same fiberglass and balsa wood structure as the Catalyst with minor changes to the roof to allow for a roof-mounted charging rails and battery. The height of the roof is shorter compared to other buses.
The ZX5 is offered with three different battery capacities:
Each of which is offered with either two Parker Hannifin GVM310 electric motors (Duo Power), or a single UQM Technologies HD250 (ProDrive) motor.
DuoPower models use two independent motors, which operate at a claimed 13.9 to 25.1 mpg-e (242 to 134 kWâ h/100 mi), although they depend on battery and body length.
ProDrive models use a single motor, with slightly lower equivalent efficiency, from .
Curb weights range between for the 35-foot models and between for 40-foot models with ProDrive models being approximately heavier than their DuoPower equivalents.
In 2022, Proterra introduced an updated ProDrive 2.0 which pairs the motor with a four-speed transmission from Eaton with electric shifting.
After Proterra's bankruptcy in August 2023, the transit bus manufacturing division was sold to Phoenix Motorcars, under which the ZX5 is now manufactured. The Proterra's branding has been replaced with Phoenix's own on models released after that date.
The ZX5 is charged using the SAE J3105 (OppCharge) overhead charging protocol while stopped on a layover (opportunity charging), or with a plug-in J1772 CCS DC fast charger when parked in a storage yard.
With any battery option, the ZX5 can be fully charged in about 2.9 hours using the OppCharge system, which offers a maximum charging rate of 330 kW. With plug-in charging, the standard ZX5 takes around 2.9 hours to be fully charged, while the ZX5 MAX takes around 4.7 hours to be fully charged at a more limited rate of 132 kW. One CCS charge port is standard at the rear curbside corner and an additional CCS port can be added either at the front curbside or rear streetside corner.