Looks like a limo, but I suppose if David Cameron has one, it must be green…
We’re not sure how much Tory-boy’s ‘celebrity’ endorsement is worth, but the Lexus GS450h is probably the most technically advanced ‘green’ car currently available as a standard-production model. It’s a big executive saloon with a premium badge and is priced accordingly, from £38,068. But that high price allows Lexus to include one of the most sophisticated powertrains offered in any car, at any price. Lexus doesn’t make much profit on these. The GS450h will hit 60mph in just 5.9 seconds (BMW 550i: 5.6 seconds) yet return a claimed 35.8mpg and emit just 186g/km of CO2 when most of its rivals are off the company car-tax dial.
But it’s just a posh Prius, right? What’s so special about it?
Yes, it’s a hybrid. But even without the help of the electric motor, the 3.5-litre petrol V6 (with 292bhp and unique twin direct-injection ports in each cylinder) has the lowest NOx and hydrocarbon emissions of any internal combustion engine. Fed by a 288V nickel metal-hydride battery pack behind the rear seats, the electric motor has its own two-speed gearbox and gives 197bhp and an instant 203lb ft of torque. Like the Prius, it can propel the car silently and unaided at low speeds and light throttle openings. Working together, the petrol and electric motors make 341bhp. Sadly, you can’t just add the two power outputs together.
Faster and greener? Sounds like a no-brainer, if you can afford it.
Not quite. Hybrids do very well on the government’s artificial urban fuel consumption test, over 30mpg in the case of the GS, but we’d be amazed if you managed that in real traffic. This skews the overall consumption figure and the official CO2 figure. If you’re a company car tax payer or drive into central London you’re unlikely to care what the real figures are. The GS450h is congestion charge exempt simply by being a hybrid, and the official CO2 stat means it is taxed at 21 percent. Most of its rivals get hit for the maximum 35 percent. So for some, it’s a financial no-brainer. For the rest of us, real-world driving will prove the GS450h to be less thirsty, and therefore less polluting than its conventional rivals, but not by the margin the official figures suggest.
So it’s not all that green. But it is really fast, right?
Again, the figures don’t tell the full story. Yes, it’s very rapid for a near two-tonne car, and the electric motor contributes its slug of torque instantly, giving the acceleration a real kick-in-the-backside quality. But the CVT 'box means there’s no rising engine note to excite you – just a faint, constant and very Lexus-like whirring. Same goes for the chassis. It’s competent and grippy, but with little of the involvement and poise of some of its rivals. The ride is quiet but occasionally choppy. The variable-ratio steering never feels odd but never feels really connected either.
Please tell me that the Lexus quality lives up to billing, at least…
Oh yes. The GS450h is magnificently made. The cabin, like the exterior, might not be particularly thrilling to look at but it is constructed with a precision to shame its rivals and the ergonomics are pretty much beyond reproach. The touch-screen controlling most of the cabin functions is the star turn, making a very complex car very easy to use and making you wonder why Audi and BMW persist with i-Drive style rotary controllers. And of course it displays graphs and charts tracking your consumption and the workings of the hybrid system, just like the Prius. Boot space is the biggest issue because the batteries occupy so much of it. You’ll need to think long and hard about whether you can live with just 280 litres (5-series: 520 litres) before you order the hybrid.
There are lots of reasons to choose a GS450h: the financial benefits, the pace, the cabin, the slightly anoraky pleasure to be had from its in-your-face technology, or the desire to be a little greener. Just don’t expect to be thrilled by the dynamics, seduced by the looks, or amazed at how infrequently you pull up at the pumps.