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Prius Prime: Mobility Meets Technology

by Ron CoganMay 3, 2017
Toyota’s 2017 Prius Prime aims to fill the needs of drivers who love the efficiency of the ubiquitous Prius but want the added benefit of a plug. As is the case with most hybrids, all-electric drive in the conventional Prius hybrid is limited to very short stretches with light pressure on the accelerator, otherwise it’s […]

2017-prius-prime-front-1Toyota’s 2017 Prius Prime aims to fill the needs of drivers who love the efficiency of the ubiquitous Prius but want the added benefit of a plug. As is the case with most hybrids, all-electric drive in the conventional Prius hybrid is limited to very short stretches with light pressure on the accelerator, otherwise it’s running on gasoline-electric hybrid power. The Prius Prime changes this with truly usable battery electric range before resorting back to hybrid propulsion.

Prime is a significant advance for Toyota as the company seeks to establish the highest conceivable standard for a plug-in hybrid, all packaged in edgy sci-fi styling. Think Blade Runner and you’re not far off, but in a clean Zen environment. Three distinct models of the Prius Prime are offered to fit varying tastes, including the Prime Plus at $27,100, the Prime Premium at $28,800, and the Prime Advanced at $33,100.


All Prime models share their silhouette with the Prius Hatchback but with unique front and rear end treatments. Prime is also 6.5 inches longer and just a bit lower and wider than the standard Prius model. To achieve increased front and rear head room, engineers lowered placement of the gasoline engine, electric motor, and seats. An additional benefit Toyota designers targeted was slippery aerodynamics, which they achieved with a coefficient of drag of just 0.25 – lower than most sports cars. Less wind resistance is an important element in achieving Prime’s exceptional fuel efficiency of 54 combined mpg as a hybrid and 133 MPGe when running on battery power. With an estimated driving range of 640 miles, Prime will outrun most anything for distance. EPA estimates an all-electric range of up to 25 miles.

We spent time behind the wheel of a fully-equipped Prime Advanced model on twisty mountain roads and highways to get a feel for Toyota’s new plug-in hybrid. Our test drive included stretches of high speed curves with little traffic, where we found the Prime Advanced doing quite well with good mid-range power while passing on two-lane roads. We’ve driven a friend’s first-generation 2016 Prius Plug-in Hybrid regularly over the past year and found it very efficient, but mundane and cumbersome on our own mountain road. A few fast turns into our drive instilled much more confidence in Toyota’s latest plug-in hybrid as we continued increasing our speed in turns.

2017-prius-prime-tire-detail-1The Prime’s major improvement in handling stems from a much more grounded feeling in turns, a nod to the Prime’s use of independent McPherson strut front suspension and double-wishbone rear suspension, with stabilizer bars front and rear. This is what some of the better-handling sports car utilize for their superior driving characteristics. Another significant change to enhance handling was moving the car’s 287 pound lithium-ion battery to the rear, with the weight transfer making a big difference in balanced handling. The only thing that holds you back from driving faster is the squeal of tires that are primarily designed for fuel economy.

Prime uses all-season P195/65/R15 tires mounted on 6.5J X 15 inch 5-spoke aluminum wheels. There are no optional wheel or tire choices and no spare. For tire repairs there is a repair kit and three years of 24-hour roadside assistance at no charge. Prime’s basic warranty is 36 month/36,000 miles with an additional 60 months covering the powertrain, with no mileage limitations. Hybrid-related components including the HV battery and modules are covered for 8 years/100,000 miles.

2017-prius-prime-engine-1Toyota’s Hybrid Synergy Drive powers all Prius Prime models using a dual motor drive. This dual motor capability did not come with the addition of a second drive motor, but rather repurposing the drivetrain’s motor-generator (MG1) for additional use. In this configuration, a one-way clutch engages both MG1 and the car’s primary electric drive motor (MG2) for motive force, the first time MG1 has been used in this way. During deceleration, regenerative braking recaptures electrical energy through MG1 and stores this energy in the battery for later use. Energy is supplied to the motors via an 8.8 kWh lithium-ion battery pack. The gasoline engine used in this hybrid powertrain is a 1.8 liter, 95 horsepower Atkinson-cycle four- cylinder. Combined, the engine and motors deliver 121 net system horsepower.

For some, the best new feature will be changes in charging requirements. While the Prime’s 8.8kWh battery delivers over double the energy of the previous Prius Plug-In’s battery pack, no special wall charger is needed. Just plug it into a standard 120-volt household outlet and in less than 5 1/2 hours you’ll have a full charge. Toyota recommends a dedicated 15A GF1 outlet for this. Faster charging in under two hours is achieved using a public charger or a 240-volt home charger, if desired.  Prius Prime apps can manage charging, locate charge stations, set climate control, and handle numerous other functions that take advantage of the Prius Prime’s connected capabilities.

2017-prius-prime-plugged-in-1Different operating modes can be selected. EV Auto Mode will automatically rely on electric capability in urban driving and during short trips. Under certain driving conditions such as negotiating steep hills, Prime’s gas engine will kick in to provide additional power. Selecting Hybrid Mode uses the gas engine for primary drive force with supplemental power from the electric motor. Power is transmitted via a planetary-type continuously variable transmission.

The most distinctive styling elements of Prime are its quad LED headlights that give this car its futurist look. These automatically adjust brightness to its environment and oncoming cars. Without a doubt, a Prime will always be readily identifiable at night given its full-width LED rear light panel that follows the shape of the double-wave rear window and spoiler. In fact, the first time you see a Prime on the road at night an immediate impression might be that of a new Lamborghini…the taillights have that kind of styling impact.

2017-prius-prime-rear-detail-1Contributing to the Prius Prime’s overall light weight of 3,375 pounds is a rear hatch made from carbon fiber. This superior strength material is usually only found on exotic or race cars due to its expense. In this application it is used for lightweighting purposes and to make opening and closing the hatch effortless. Rear visibility is enhanced by a full-width glass panel and standard backup camera.

All Prime models feature a four-seat layout with a center console front and rear, with 60/40 folding rear seats. The front console has a handy wireless charging pad for Q-i compatible devices. Auxiliary 12-volt power outlets are provided up front and in the rear, with a USB 2.0 port for iPod connectivity and control standard. The shiny white plastic used for the console has a Star Wars trooper look to it and may be too bright for some tastes. A 4.2-inch gauge panel mounted above the dash is considerably easier to read in daylight than that of the previous model. A heads-up display is available.

2017-prius-prime-cabinThe most obvious interior feature is Prime’s optional 11.6-inch tablet-like HD multimedia screen that’s mounted vertically in Premium and Advanced models. A standard Entune multimedia system provides audio, navigation, and an App Suite. Suffice to say if it’s on the market, Prime has bundled it...unless you want to play CDs. Apparently there is no place for CDs in the future. Audiophiles will be particularly pleased with the Prime Advanced model since it includes JBL audio with 10 speakers and delivers an exceptional concert hall experience.

For those who find parking a challenge there’s the Advanced model’s included Intelligent Clearance Sonar (ICS) with Intelligent Parking Assist (IPA). Once selected, the system’s sonar sizes up an available parking space and reverses the car into the space. Perpendicular spaces are also negotiated, plus it will also steer you out of a parallel spot.

2017-prius-prime-display-1The Prime's Safety Sense P list of standard safety features is as impressive as it is extensive. Prime bundles a Pre-Collision System with Pedestrian Detection and Automatic Braking, Lane Departure Alert and Steering Assist, Full-Speed Dynamic Radar Cruise Control with full stop technology, and Auto High Beams. The Advanced model adds Blind Spot Monitor and Rear Cross Traffic Alert. Also, there are eight airbags for additional driver and passenger safety.

Toyota is out to raise the standard by which plug-in hybrids are measured. They have done so with the Prius Prime by adding leading edge technology systems coupled to a powertrain that is a marvel of efficiency. Factoring in a price reduction in the thousands from the earlier generation Prius plug-in and an expanded 25 mile battery-only driving range, this Toyota model certainly holds appeal for Toyota Prius fans and new converts to a plug-in hybrid society.