What is it?
This is the fourth-generation Toyota Prius, the petrol-electric car that played a huge role in kick-starting the acceptance of hybrids when it first appeared in 1997.
The new Prius is the first model to be based upon the Japanese manufacturer’s new TNGA modular architecture, said to bring advantages in terms of interior space, mechanical packaging and chassis sophistication. In turn, that should mean a car that offers a more involving driving experience than the outgoing model.
However, the emphasis is still on remarkable fuel economy and low CO2 emissions, and in that respect the new Prius has taken a significant step forward. According to Toyota’s own figures, it emits an impressively low 70g/km of CO2 and is capable of 94.1mpg.
At 4540mm, the new car is 60mm longer than the Prius Mk3. It is also 15mm wider and 20mm lower, while retaining the same wheelbase of 2700mm, and has a more slippery shape than of old.
The now more compact powertrain components in the front of the car have been positioned 10mm lower than before. Toyota claims the new platform helps to lower the centre of gravity and that, allied with a 60% increase in body rigidity and revised front and rear suspension, gives the Prius improved handling response and agility.
Not everything is new about this Prius, however: it retains the 1.8-litre petrol engine used by its predecessor – codenamed 2ZR-FXE – although the unit has been significantly overhauled.
Toyota claims to have improved the engine’s maximum thermal efficiency from 38.5% to 40%, which is an impressive figure for a petrol unit. The petrol engine produces 97bhp while the electric motor makes 71bhp.
The electric motors in European versions of the car will continue to be fuelled via a nickel-metal hydride battery pack, albeit a newly developed version compared to that used by the third-generation Prius. Toyota claims the new battery is smaller than the old one, and can recharge via the generator more rapidly, by as much as 28%.
The reduction in size, allied with the packaging possibilities of the new TGNA architecture, mean the battery has been shifted even further under the rear seats, freeing up 56 litres of extra boot space in the boot of the new Prius to give it a total capacity of 502 litres. The rear bench splits 60/40 for more load carrying space. This is also the first Prius to be rated for towing, with an unbraked capacity of 725kg.
What's it like?
The minimalist cabin features fewer buttons and switches than the Mk3 car. The shift to the new TNGA platform has reduced the height of the top lip of the bonnet by 620mm, allowing more light into the cabin and providing better visibility for the driver.
The feeling of spaciousness provided by increases in front and rear head room is emphasised by the thinner frames on the quarter glass ahead of the door mirrors; on the previous car, the elements were obscured by thicker pillars.
The previous car’s distinctive centrally mounted instrument panel is retained, although it is less recessed into the dashboard and has sharper graphics, making it easier to read at a glance than the old design. The main infotainment screen is larger, and the climate controls simplified.
The foot-operated parking brake also remains, freeing up space between the front occupants. The stubby gear lever is familiar, too, albeit mounted higher on the central stack than before.
There is a lot of plastic on show, although the materials used for the main points of contact are of an acceptable quality, and there’s some silver brightwork to lift the ambience. Some ergonomic quirks remain: the switches for the seat heaters are inexplicably hidden behind the floating central stack, a full arm’s stretch away.
Our first test of the car came as part of a strictly speed-controlled convoy run over two laps of the Toyota-owned Fuji Motor Speedway.
Operation of the new Prius is child’s play to anyone familiar with hybrids – and with EVs, for that matter. Press the power button to the right of the steering wheel and the car chimes into life, showing the ‘ready’ prompt on the instrument display.
The battery-powered component of the petrol-electric Hybrid Synergy Drive system propels the car silently away from a standstill, with the petrol engine kicking in quietly and smoothly at higher speeds.
Toyota has also tweaked the power delivery to provide more linear, consistent acceleration, smoothing out the curve by using more of the battery’s power; floor the throttle and you hear less of the engine’s buzzsaw drone that was a trait of the previous car, although it hasn’t been eradicated entirely.
Three drive modes – Eco, Normal and Power – are available at the press of a button, although Normal seems adequate in most occasions. Power mode is said to provide more throttle response, but the difference feels minimal.
Of course, this car’s unique selling point isn’t its performance – and driving a Prius in an over-enthusiastic manner traditionally plays havoc with the fuel economy – but the Toyota is definitely more composed during cornering than before, steering fairly precisely and cornering in a neat, flat manner. The brakes, too, have been improved, providing a more progressive and ‘natural’ feel that was somewhat corrupted by the regenerative braking system on the old car.
The ride of the old car could feel harsh and fidgety over uneven roads; Toyota’s claim of an improvement brought about by the new suspension felt valid on a smooth race track, but we’ll require a more thorough test on UK roads.
Should I buy one?
If you need a hybrid family car that doesn’t need to be introduced to an electric socket on a regular basis and you drive more in urban areas than on motorways, the new Toyota Prius looks likely to be worthy of consideration, especially for company car drivers.
However, a price tag of £23,295 puts the Prius up against a wide range of high-quality, efficient petrol and diesel vehicles from Toyota’s mass-market rivals.
It’s a case of small gains in lots of areas as opposed to a revelatory leap in any one, but given the roaring success of the Prius in many markets, it shouldn’t be a surprise to discover that Toyota hasn’t deviated far from the popular and successful template.
Location Japan; Price from £23,295; Engine 4 cyls, 1797cc, petrol plus electric motors; Power 121bhp; Torque 105lb ft; Kerb weight na; 0-62mph 10.6sec; Top speed 112mph; Fuel economy 94.1mpg (combined); CO2 70g/km, 9%