Performance & drive
What it’s like to drive, and how quiet it is
The Volvo T8 plug-in hybrid (PHEV) engine is branded 'Recharge' in the S90 brochure. It has a battery pack powering a 141bhp electric motor that drives the rear wheels and a 299bhp 2.0-litre petrol engine powering the front ones.
Combined, that means near-instant response the minute you put your foot down and plenty of poke after that, with 0-60mph cracked off in just 4.5sec. For comparison, the 530e BMW 5 Series is nowhere near as quick, but the 545e is much closer to the S90 in terms of straight-line performance.
The S90 is lovely and quiet around town in electric-only mode, and a quiet cruiser on the motorway. There's little in the way of wind noise, even on the motorway, and road noise is okay – the standard fit 19in wheels drum up a bit of a roar over coarse surfaces. The Audi A6 and 5 Series are slightly quieter in that respect.
Ride comfort in luxury cars is crucial to many buyers, so it’s disappointing to find that the S90 doesn’t deal with bumps that well. Around town, there’s more fidget than you’d feel in an A6, and large ruts send a thump through the car. R-Design trim comes with a lower suspension set-up that makes the ride a bit harder still.
At the same time, the large S90 isn't as sharp as its rivals when it comes to handling – it's less precise than the 5 Series and the Jaguar XF. It remains fairly upright through tight bends but never feels particularly eager to change direction and the steering doesn't provide much feedback.
R-Design trim provides a slightly tauter driving experience, but ultimately it's not worth the compromise in ride comfort and there is still quite a lot of float on undulating country roads. The fact that all four wheels are driven by either electricity or petrol does give the S90 good traction in trickier driving conditions, but in terms of handling balance, it still feels predominantly front-wheel drive.