There’s always something reassuringly comforting when I see a Volvo listed among the cars that I’m scheduled to review, like sliding my weary feet into a pair of my favourite old slippers.

Now I appreciate that might not sound like the most promising start to a review but bear with me and you’ll start to appreciate that, despite how it sounds, the slipper analogy is, in fact, a significant compliment.

The cabin is gloriously well-appointed. You’re surrounded by premium materials. There are no brittle plastics or hard surfaces on show, Instead there’s brushed metal inserts, lots of leather, splashes of wood and an obvious attention to detail.

There is a real sense of peace and calm in the cabin, something that’s apparent the moment you climb aboard, and that relaxed ambience is a theme that flows through the car from front to back and top to bottom and makes the passenger space a genuinely pleasant and welcoming place to be.

The first thing you’ll notice when you climb aboard is the tablet-like touchscreen that dominates the centre console. The next thing you’ll notice is the lack of buttons.

All the systems on board – climate control, Bluetooth, DAB radio and sat nav – are controlled via the tablet-like touchscreen that dominates the centre console. While the portrait orientation might be unusual in a car, it will be reassuringly familiar to the smartphone generation.

I wouldn’t describe the interface as immediately intuitive – I refuse to refer to a user manual unless lives are at stake – but it doesn’t take too long to become acclimatised.

Sensus also gives access to a wide variety of cloud-based applications including internet radio, finding and paying for parking, connected navigation as well as MirrorLink and CarPlay.

Equipment levels, if you haven’t already guessed, are generous. There’s LED headlights, powered tailgate, 10-speaker 300W audio system and adaptive cruise control as well as a host of safety features that includes a Run Off-Road system that detects if you’ve run off the tarmac and prepares the car for a crash and energy absorbent seats that will reduce the impact of a big smash.

There are, of course, systems to prevent you crashing in the first place, such as an autonomous braking system that stops you turning across the path of an oncoming vehicle and lane keeping assistance which monitors the white lines and will gently turn the wheel to keep the car between them.

Head and legroom is excellent in the first two rows but, while the occasional seats in the boot will accommodate adults, you’d have to have a particularly cruel streak to ask anyone whose hips are no longer their own to try and clamber into them. Taller people will also find space for their long limbs limited in the third row while headroom is reduced too.

Even with the rear seats in place, the boot is a very useful 451 litres. Fold the rear seats away and that rises to 1,102 litres. Not enough? Stow the middle row away you’ve got 1,951 litres to play with. The loading lip is low and, with the powered tailgate, all that space is easily accessible.

So far so good then. Volvo’s premium SUV lives up to its billing.

Now, what’s unusual about this particular model is what’s under the bonnet because this, the B5, is only version of the XC90 to run on diesel. It’s also a mild hybrid, which means that it can store some of the energy that would usually be lost under braking and use it to power an electric motor that eases the stress on the engine and, by doing so, improving efficiency and lowering emissions.

The B5 replaces the D5 in the line-up and brings with it a – claimed – 15% increase in efficiency. That equates to – again this is the manufacturer’s figure, not mine – an impressive 44.1mpg. It isn’t all good news, though, because while emissions are pegged at 154 bits of carbon dioxide for every kilometre driven, the B5 still falls into the top benefit-in-kind bracket of 37%.

Being a mild hybrid means that the XC90 can’t drive using electrical power alone. Rather the motor assists the diesel in its efforts. It’s seamless in its operation. The engine picks up smoothly from low revs and effortlessly accelerates to motorway speeds.

The eight-speed automatic gearbox operates discreetly in the background right up until you put your foot down – either from a standing start or on the move – and there’s just a moment’s hesitation before there’s any response. It can be a frustrating experience but, fortunately, if it does become a little more than you can bear there’s a pair of paddles behind the steering wheel so you can take over and swap ratios manually.

Refinement is excellent. Aside from a little grittiness when you’re pulling away the engine never really sounds stressed even when you accelerate hard. There’s a little more road noise than you might expect but there’s very little in the way of wind roar so progress is generally very relaxed.

It’s a big car and the B5 carries an additional 130kg compared to the petrol models but the handling remains tidy enough. There’s very little body lean unless you’re tempted to really throw it into a corner and, really, why would you? The ride can feel a little wallowy over undulations while higher-frequency imperfections make it fidget.

The steering is quite weighty – something I appreciate but others almost certainly will not – and there’s a dead spot around the straight-ahead. That’s a boon for straight-line stability, of course, but it makes it very difficult to place the XC90 if you are trying to hustle it along.

It’s beneath the skin when the most significant differences between the B5 and the model it replaces, the D5, occur. It makes considerable gains in both economy and emissions and fills a niche beneath the T8 plug-in hybrid which, although capable of running on electric power alone, is significantly more expensive.

Volvo XC90 B5 AWD (diesel) Inscription Automatic

Price: £57,335

Engine: 4-cyclinder diesel

Transmission: 8-speed automatic

Max power: 235hp

Max torque: 480Nm @ 1,750 – 2,250rpm

Max speed: 137mph

0-62mph: 7.6sec

Fuel consumption (WLPT) mpg –

Low: 31 - 34

Medium: 39.2 – 45.6

High: 43.5 – 52.3

Extra high: 36.2 – 42.8

Combined: 37.7 – 44.1

Emissions (CO2): 154g/km

For more information visit www.volvo.co.uk