Who says the wealthy can’t be green? Not Lexus, that’s for sure, for this company has launched a range of upmarket hybrid models.

Until recently hybrids – which blend traditional engines with electric motors – have tended to be family cars such as Honda Insight and Toyota Prius.

But Lexus, the luxury wing of Toyota, believe even customers of £50,000 models have a conscience and want to be seen in something ‘green’. That’s why we have the Lexus GS450h. I know, it sounds like a constellation or a brand of laptop, but it is in fact a groundbreaking car.

It’s a rival to BMW 5 Series, Jaguar XF and co in that it’s a premium saloon with sporty pretensions. But it’s powered by a 3.5 litre petrol engine and an electric motor which combine to offer the sort of economy you might get from a family hatchback: 45.6mpg on a combined route, 40.9mpg around town and almost 50mpg on a run.

Excellent. But it also offers proper sporting performance which will whisk you to 60mph in 5.9 seconds and on to 155mph where legal.

So, let’s deal with the technology first. Lexus executives are convinced that the sort of people who buy £50,000 cars (entrepreneurs, successful civil servants, third division footballers and the like) want to be eco-friendly.

This model has a very traditional 288bhp petrol engine and a superbly smooth stepless automatic gearbox, which means it ‘s incredibly smooth.

The clever bit is that it also has a 197bhp electric motor powered by a nickel-metal hydride battery.

The GS 450h is the world’s first front-engine/rear-wheel drive premium performance saloon to be equipped with a petrol engine and electric motor full hybrid system.

The result is incredible. It looks, feels, sounds and handles like a premium performance saloon which stands comparisons with Jaguar, BMW, Audi, Infiniti and co, yet offers very good economy.

This is the fourth generation of the GS range which has become a mainstay of Lexus, first launched as an upmarket brand of Toyota in the same way that Infiniti is a posh Nissan.

It is a striking looking car, far more distinctive than previous GS models. It has a very macho front end which looks like something Batman may drive, and the overall look and build quality is admirable.

Inside, the design is great. I love the seats, probably the most comfortable in any car I’ve driven, and the huge 12.3in colour screen is the biggest and clearest on the road.

Some of the switchgear doesn’t quite cut the mustard, though, but I do like the leather and chrome which makes for a very smart and comfortable motor.

It’s a big car with plenty of space, but oddly it’s a four-seater rather than a five-seater. The middle of the back seats is strangely raised.

You might imagine a £50,000 Lexus to be well-equipped, and you’d not be wrong. Some of the most impressive features included a combination of traction control, stability control and adaptive suspension which made for a remarkably smooth car, yet one which could turn on the power in an instant.

The 12-speaker audio system was stunning and the computer centre which ran the satellite navigation and information on the power output of the engines was simply fantastic.

Another key aspect of what defines a Lexus is quietness, and on smooth European tarmac it’s at least as quiet as anything else you care to mention for less than £60,000.

Hybrid power might not be for everyone, but if it was always as polished and fuss-free as this impressive motor, it would surely be the power of choice.

Lexus GS450h Sport PRICE: £50,995 ENGINE: A 3,456CC V6 engine emitting 286bhp, plus an electric motor with continuously variable transmission (CVT) PERFORMANCE: Top speed 155mph and 0 to 60mph in 5.9 seconds COSTS: urban 40,9mpg; extra-urban 49.6mpg; combined 45.6mpg INSURANCE: Group 42 EMISSIONS: 145g/km WARRANTY: Three years, 60,000 miles