Potential owners of the new Lexus LS600h L may spot a serious omission as they thumb through glossy brochures that extol the reasons to buy one of the world’s most technologically comprehensive and luxurious cars: the options list does not include a bath towel. But one may be thrown in as standard equipment when word gets out about the sleeping arrangements in the long-wheelbase Lexus.

Of its four sumptuously upholstered, multifunctional seats, the rear nearside is the one that – in the best tradition of German sunbed-claiming – could have a towel in place.

And for good reason: settle on to the cushion, push a button and the backrest reclines up to 45 degrees to assume semi-bed mode as the front passenger seat moves forward, its headrest lowering.

Simultaneously, an Ottoman-style thigh and foot support rises and a massage system starts its soothing work to a menu including Shiatsu and shoulder and lower-back acupressure. An overhead 9in DVD screen unfolds and, yes, there is a fridge for the champagne, too.

But what about the environmental message? Ah, could that be the car’s 5.0litre, 389bhp V8 petrol engine, 155mph top speed or 0-62mph time of 6.3sec? No, it is all about a little letter in the big Lexus’s name: h for hybrid, a clever piece of petrol-electric motive power allowing 2.5 tonnes of wheeled magniloquence to return a combined fuel consumption better than 30mpg and modest CO2 emissions of 219g/km – which is not to be wheezed at.

That really is the point of the Lexus LS600h L: super luxury and high performance with moral responsibility, and all for a paltry £88,000, with prices from £81,400 for the shorter wheelbase version that has more modest seating arrangements.

Toyota – Lexus’s parent company – is well versed in the hybrid art. The Toyota Prius has demonstrated that many people in Europe buy cars for emotional, “green” conscience reasons rather than as the result of equations based on simple arithmetic and cost-benefit ratios. The hefty Lexus extrapolates this thinking by two sizes and takes it into the boardroom because the LS600h L is very much a chairman’s experience.

There is no denying that, assessed for its superb quality and V12 engine-like capabilities, the all-wheel-drive, aerodynamic, hybrid Lexus is a magnificent achievement, with highly advanced safety systems not to die for. It also has surprisingly good handling to consolidate the cossetting experience of travel that it provides.

Driving, or being driven in, this car is a sound-of-silence experience that shrinks long journeys. It may look as stately as a galleon, but it moves like a powerboat, its two-stage electric motor (producing an almost instant 300Nm of torque) and that big petrol engine working together to provide a huge total of usable energy: 439bhp. Treat it gently, though, and the Lexus moves off with a mere hint of decibels.

The majority of Lexus LS600h Ls will be bought by companies. Lexus says that about 10 per cent of buyers will have previously owned a Bentley and 60 per cent will have had a Mercedes-Benz SClass or BMW 7 Series. The Mercedes and BMW, together with the excellent Audi A8, are arguably its nearest rivals, each available with diesel engines that have relatively modest fuel consumption and emissions figures, without electric motor assistance.

So to achieve exceptional frugality, why does Lexus not produce a diesel-electric hybrid for Europe? It would have to refine vibration, noise and some other issues, but Lexus is doubtless sufficiently clever to achieve that. And the added cost of a diesel engine at Lexus’s heady price levels should not be a problem.

It could just happen – because Lexus is on a hybrid high and plans to stay there as others challenge. That’s one towel it will not be throwing in.

Mondeo victorious

The troubled car giant Ford has been given a welcome boost by the news that the new Mondeo has been named Car of the Year. The Mondeo was voted the best new car by Auto Express. It was also named best family car and best estate car in the magazine’s annual New Car Honours.

Specification

Car Lexus LS600h L
Engine 5.0litre V8 389bhp, 520Nm of torque; electric motor 300Nm of torque; maximum usable combined power 439bhp
Transmission CVT; four-wheel drive
Performance 0-62mph 6.3sec; top speed (limited) 155mph
Combined fuel consumption 30.4mpg
CO2 emissions 219g/km
Price £88,000
On sale October 1
Very posh alternatives Maybach 62 Even better sleeping quarters
Rolls-Royce Phantom Ghastly good taste vies with craftsmanship
Bentley Flying Spur Relatively modest, rapid
Less lavish alternatives Audi A8 4.2 diesel quattro LWB Fine car inside and out
Mercedes-Benz S320 CDi L diesel Luxury, diplomatic corps image
BMW 730Ld SE Good drive, but odd styling