Half-electric Frankenstein. After years of niche obscurity, hybridization is finally in the limelight. The technology has been proven, government tax credits incentive them, and – most critically for commercial success – they have finally been accepted as cool by consumers.

Was the Toyota Prius Prime one of those trendsetters that finally changed the attitude of the buying public? That's an emphatic no. The 2021 Toyota Prius Prime remains a, ah, prime example of unpretentious eco-conscious motoring. It has no handling or performance chops and its styling is to be tolerated rather than enjoyed. But the Prius Prime has the Toyota reputation and the Prius heritage to undergird it, and, for many buyers in this segment, that's merit enough.

Slow but miserly. The Prius Prime's biggest attraction is, of course, its gas-electric powertrain. The conventional bit is a 1.8-liter inline four-cylinder; the fancy stuff consists of dual electric motors and an 8.8-kWh battery pack.

All told, total power output is a rather meager 121 horsepower. But the only race the Prius is out to win is the sprint to 60 mpg. It doesn't quite make it there but gets closer than most vehicles, netting an EPA-rated 55 miles per gallon city and 53 mpg highway when the gas engine is in play, and 133 MPGe combined is possible while exploiting the 25 miles of all-electric range.

The Prius Prime drives like it looks: unpleasant. Slow and uninspired, the pokey plug-in feels quick enough around town but loses all pretense of power at speed. Passing on the highway is an endeavor best avoided. On-ramps and steep grades are likewise a challenge. Heaven help any hypermiler who looks at the efficiency gauge during one of these maneuvers, all of which require drivers to hammer the accelerator.

A continuously variable transmissions does the shifting, and the worst tendencies of this transmission type have largely been ironed out here. On the gearshift, drivers will find a "B" button; pressing it increased the regenerative braking action. The additional regen action is noticeable, and when engaged drivers will feel the car readily slow down as soon as they lift off the throttle. It's a nice way to recoup a bit of energy and save the brake pads from some wear.

Plugged into an ordinary 120-volt outlet, the Prius Prime's lithium-ion battery takes about 5.5 hours to fully recharge. A 240-volt outlet cuts that time down to around 2 hours. Once the battery is fully depleted, the electric motors go on hiatus and the gas engine takes over running the car. Not that you'd notice – the transition between gas and electric propulsion is always seamless.

Toyota Prius Prime

Austere, well-equipped. Like all Prius models, the Prius Prime's cabin feels austere. The acres of black plastic and a basic and uninspired design don't make it a very enjoyable place to spend time in.

The most disconcerting factor initially is the lack of a traditional gauge cluster. In proper Prius tradition, the Prius Prime relocates all pertinent travel and vehicle information information to a digital readout mounted atop the center stack, leaving only an expanse of black plastic ahead of the steering wheel. The placement isn't as odd as it looks, and after a few trips it becomes as second-nature as looking at the radio.

As for the radio, it's embedded in an 11.6-inch touchscreen. That's some generous screen size, but the software that powers it could use some help. It takes a second for inputs to register, resulting in an annoying lag when trying to tap menu icons. It isn't the most intuitive system, either. The good news is that Android Auto compatibility is finally part of the deal. Along with Apple CarPlay, it comes standard on all models.

Keeping with the rest of the interior, the seating isn't luxurious. Cloth upholstery is standard on all trims. Base models get manual seat adjustment; higher trims get eight-way power adjustment. The fronts are comfy enough, though they wouldn't be our first choice of thrones for a road trip. The back seat only has 33.6 inches of leg room, which is too little for our liking. Luckily the big windows and a bubble roof imbue the cabin with an airy, expansive feeling.

Encroaching competition. For a few years, the Prius Prime occupied a niche that was really only rivaled by the Chevrolet Volt; other alt-energy options were all-in on electric power or, if they were hybrid, could only muster a handful of miles on a charge. As with the Volt, the Prius Prime's useful range of gas-free motoring made it an ideal in-town runabout, while the engine remained for the inevitable moments when a road trip was on the calendar.

That then-unoccupied middle ground gave the Prius a unique advantage among consumers still leery of making the leap to all-electric cars. But electric cars and plug-in hybrids have only become more prevalent and more accepted among buyers. With a raft of alternative options on the market, the Prius Prime – along with the rest of the Prius family – doesn't dominate the sales charts like it once did. In a sign of the times, the Prius lost its title as best-selling hybrid to the Toyota RAV4 Hybrid in 2019.

Compared to the Prius Prime, the RAV4 Prime carries more cargo – 50 total cubic feet versus 63 cubic feet – and is significantly faster with 302 total horsepower. Not to mention the RAV4 Prime looks like a typical contemporary crossover, not a creature of the deep. The RAV4's only drawback over the Prius is price: the cheapest RAV4 Prime costs nearly $10,000 more than a base Prius Prime.

A more apt comparison is the Hyundai Ioniq. Since its introduction in 2017, the Ioniq has aimed its sights on the Prius family. Like the Prius, it's a hybridized hatchback that costs around $34,000 fully loaded. Its plug-in hybrid model can go 29 miles to a charge, four miles further than the Prius Prime. The Ioniq's 119 MPGe combined rating in electric mode can't match the Prius Prime's 133 MPGe, however. It remains one of the most efficient cars on the market.

Other competitors that have the Prius Prime pulling at its collar are the Honda Clarity, Ford Escape PHEV, Honda CR-V Hybrid, and Kia Niro PHEV. Many of these didn't exist just a couple of years ago, and more are coming still. Though each of these are unique in their own way, all are affordable plug-ins that marry practicality, usability, and conventional design with Prius-like efficiency.

Final thoughts. The 2021 Toyota Prius Prime, if it wants to remain competitive, will need to up its game. The Toyota reputation won't carry it much farther if the vehicle is objectively inferior to its competition.

Right now, it remains one of the most energy-efficient vehicles you can buy, but many of the aforementioned competitors are nipping at its heels. The odd looks and staid interior don't help matters, either. As miserly as the Prius Prime is, we would give close consideration to some of the other similarly-priced plug-in options now on the market.

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