Toyota is filling a gap in the people-carrier market with a seven-seater Prius+ hybrid. Matt Kimberley, PA motoring writer, drives it.

By Toyota's own admission the Prius name is a bigger brand in terms of green credentials even than the company itself, so expanding the Prius range is a sensible thing to do.

Toyota has spotted a gap in the market for a seven-seat, sub-100g/km car, particularly for fleet-buyers like car hire companies, and the Prius+ aims to fill it. The lower of the two trim levels, T4, sits at 96g/km and is expected to take about 70pc of sales ahead of the 101g/km T Spirit.

Even though it works in the same way, the new model doesn't quite use the same Hybrid Synergy Drive system as the five-seat Prius hatchback, because in the latter the under-boot nickel metal hydride (NiMH) battery pack raises the load bay and means a third row of seats is not an option. For the Prius+, the new and impressively compact lithium-ion (Li-Ion) battery has been cleverly sited in the cabin centre console, beneath the arm rest. The boot floor has been lowered and a third row of seats added.

The roof line has been raised while trying to maintain a Prius shape. The middle row of three individual seats (specifically for Europe) move forward and back independently, firstly so that each of the three occupants can get more shoulder room, but also so the available space can be balanced between the two rows of rear seats.

The upshot is that you can get seven six-footers in the Prius+, even if the rearmost passengers won't want to be there for too long. That said, the practicality and intelligent management of space is impressive, and families will find a lot to like.

The five rear seats, which fold flat and create a level load floor, have a brilliant one-hand-one-movement operation, so parents with one arm full of wailing child can still set the seats up just how they need them. The boot lid is a little too heavy to be ideal, but you work around it.

With all the seats up there's 232 litres of space, not a lot but it can hold a reasonable amount of soft baggage. With the third row folded flat there's a much more impressive 784 litres, more than enough for most families. Under the removable boot floor there's a useful extra space for oddments.

If the Prius+ majors on practicality, it does pretty well at in-town driving too. One of the three selectable driving modes uses only electric power as much as possible, keeping urban emissions – and fuel costs – to a minimum. The battery is small compared to that of a plug-in hybrid so its range in electric vehicle (EV) mode is only a few miles at best, but it's surprising how well the Hybrid Synergy Drive makes that power last once rolling.

Things aren't so positive out of town. The excellent ride quality from soft, comfortable suspension means that handling falls way down its list of abilities. Equally, the constantly variable transmission (CVT) automatic gearbox that's gives smooth and quiet running at low speeds can allow the car to feel a little strained when accelerating up to A-road pace. Despite that, the ride is still very good and fuel economy at a motorway cruise is impressive for a 1.8-litre petrol car.

As always for a Prius, the seven-seater is crammed with kit. Barely scratching the surface the T4 model features a rear-view camera – although it's not entirely reliable as a judge of positioning because it's offset to one side of the number plate and gives a slightly false perspective – a panoramic roof, automatic windscreen wipers and a touchscreen infotainment system.

The mid-grey interior trim is designed for an older audience. It's totally unpretentious and will wear without looking worn. It's practical and unassuming – perfectly suited to the Prius+ target demographic, but some will call it bland.

The truth is it isn't a car designed for a mass audience. It's built to satisfy a specific set of needs, and how much your own needs overlap what Toyota's engineers were working to will reflect how good the Prius+ will be for you. People who need a seven-seat multi-purpose vehicle (MPV) with low running costs, oodles of practical touches and unimpeachable reliability will find living with this car a real joy.