A Prius with plug-in capability has been notably absent from the current generation of Toyota's popular hybrid. The new Prius Prime is the successor to the previous Prius Plug-in. Toyota offers the Prius Prime in three trim levels: Plus, Premium and Advanced. We tested a 2017 Prius Prime Advanced (MSRP $33,100). Extras such as optional Blizzard Pearl exterior color ($335), illuminated door sills ($299), body side moldings ($209), and floor mats/cargo mat ($224), plus the delivery/handling fee totaled to $35,112. Notable standard equipment includes heated front seats, 11.6" touchscreen, LED headlights and foglights.
All Prius models are powered by a 1.8L all-aluminum Atkinson cycle inline-4 with dual overhead cams and variable valve-timing (VVT-i). Toyota rates power output of 95-bhp @ 5,200 RPM and peak torque of 105 lb.-ft. @ 3,600 RPM. The 53-kW (71-bhp) AC synchronous electric motor adds 120 lb.-ft. of torque and boosts total hybrid system power to 121 bhp. Toyota adopted a larger capacity 8.8 kWh lithium-ion battery to extend maximum EV-only range to 25 miles and an impressive 84 MPH top speed in EV mode. Coupled to the gasoline engine and electric motor is an electronically controlled CVT (continuously variable transmission) that drives the front wheels. Charging the battery takes about 5.5 hrs. using a 120V outlet, or just over 2 hrs. at 240V.
As with most other Prius models, the Prius Prime is rated at 54/50 MPG (city/hwy.) and 124 MPGe. To encourage efficient driving, the trip computer records fuel consumption per trip. We averaged about 45 MPG, mainly due to short trips and subfreezing December temperatures.
Replacing the semi-independent torsion beam rear suspension in the previous Prius, Toyota installed a double wishbone setup with coil springs, dampers and a stabilizer bar. At the front are MacPherson struts and a stabilizer bar. Disc brakes are at all four wheels with an integrated regeneration system that charges the batteries. Steering is a via an electrically-assisted rack-and-pinion system. P195/65R15 all-season tires are mounted on 15-inch diameter alloy wheels with wheel covers.
The Prius continues its tradition of simple, functional interior design. Most surfaces are soft touch plastic. As before, a central instrument cluster shows a digital speedometer along with a multi-function display showing hybrid system status and fuel consumption. A new 11.6" touchscreen controls most infotainment functions, but audio volume and tuning knobs allow quick adjustments without distraction. Toyota relocated the shift lever to the center stack, convenient yet unconventional. Next to the shifter is a button to engage the EV mode that switches the Prius to exclusively electric drive. The steering wheel has duplicate controls for audio, phone and infotainment system, but the roughly textured plastic wheel rim is a disappointment. Analog audio and USB inputs are on the center console. A storage bin is located under the center armrest. Cargo storage capacity is reduced due to the larger battery which raises the load floor.
The front seats provide a balance of comfort and lateral support with manual six-way adjustments for the driver and a basic 4-way adjustability for the passenger. Rear occupants benefit from decent legroom and comfort, but headroom is limited for passengers over 6 ft. tall. An outlet on the center console supplies 12V power for portable electronics.
Toyota has focused the Prius on fuel efficiency above all, but the new Prius now offers a driving experience closer to a typical compact sedan. Ride comfort is significantly over the previous Prius, no doubt due to the independent rear suspension that replaced the torsion beam axle. The electrically-assisted steering is reasonably precise with moderate effort. Steering turn-in response is somewhat delayed, likely because of the low rolling resistance tires. Moderate understeer and significant body roll around curves confirms that the Prius has no sporting intentions. The regenerative braking system engages as necessary to recharge the battery, but sometimes this affects the conventional hydraulic brakes as the Prius decelerates faster than expected.
Driving on the highway, the Prius tracks steadily at 80 MPH. The suspension absorbs frost heaves and potholes and requires minimal steering correction. Wind and tire noise are subdued, and the CVT keeps engine revs low while cruising. At full throttle, the engine drone as the revs rise and hold steady as the CVT selects the optimum RPM for maximum acceleration. For silent running, the Prius EV mode can be engaged for extended driving up to 25 miles, depending on the battery charge.
The Prius Prime extends EV-only driving range, but with the penalty of higher cost and reduced cargo capacity. We think that the less expensive Prius models are probably a better value for most customers. For those seeking the cachet of a pure EV without the range anxiety, the Prius Prime may be the solution.