| Car Clash | Bentley Supersports vs. Tesla Roadster Sport |

The doubters now have their voice; the environmentalists are backing down and the scientists have admitted that perhaps global warming isn't happening after all. Whatever the truth, the car industry has started down a path of producing more economical and cleaner machines and that's no bad thing. Especially if the result is one of the two cars featured here.

Tesla's Roadster Sport and Bentley's Continental Supersports prove that green technology most definitely doesn't have to be boring. Both use different means to achieve their green claims - the Tesla powered by lithium ion batteries and electricity and the Bentley good ol' internal combustion, though fuelled by E85 bio-ethanol - but what's crucial to enthusiasts is that they're fast. Very fast.

In the Metal

Beside the chunky Bentley Tesla's Roadster Sport looks like a toy. It's based on Lotus Elise underpinnings and the dimensions are largely similar. Outwardly you wouldn't know the Tesla is battery powered, it looking just like a sports car should - especially with the optional clear carbon fibre pack highlighting its build material. Through the front slats you can see a radiator and fans, but other than a glimpse at a pair of large orange cables through one of the air intakes on the rear clamshell the Tesla could be just another sports car.

Like its Lotus relative there's the usual challenge getting in and out, but you quickly get used to it. No such problems with the Bentley. Sure, the seats are manually rather than electrically adjusted but getting into the Supersports is a pleasure. Outside, the Supersports wears its intent with blistered wheelarches, huge alloys covering Bentley's massive ceramic brakes and a nose that's slashed and shaped to heave air around and into the engine bay. Inside, those manually adjusted seats - and the loss of the rear ones altogether - hint at the Supersports' attempt at shifting weight. One hundred and ten kg have been removed from the Continental, but at 2,240kg it's still fighting a losing battle with the scales. Still, with 621bhp to shift it the Bentley's bulk isn't really an issue.

What you get for your Money

For the £166,600 the Bentley costs you get the most powerful, fastest accelerating car in the company's range. Sixty miles per hour arrives in just 3.7 seconds (62mph in 3.9 seconds), that conveniently exactly what Tesla quotes for the Roadster Sport model. Despite its lighter, more focussed remit the Bentley is still sumptuously appointed inside, with bank vault build solidity and beautiful hand-crafted detailing. Tesla's optional leather trim does little to lift the Roadster Sport above the feeling that it's an Elise that's been upgraded. That's not to belittle Tesla's attempts, but it's clear that the £101,900 that it costs you is largely diverted towards its innovative drivetrain.

That sizeable chunk of money buys you a lot of batteries. Lithium ion ones to be precise, which are much like those that power your laptop or mobile phone. The only way you'll get either device to go as fast as the Tesla though is to chuck them out of a high-rise window, as the Roadster Sport's electric propulsion gives it quite spectacular performance. What's important now though is that you can have your Tesla Roadster in UK spec, with the steering wheel positioned on the right-hand side of the car.

Driving it

Despite the identical 0-60mph times and the fact that the Tesla weighs a full tonne less, it's the Bentley that feels quicker off the mark, the 621bhp W12 turbocharged engine using its four-wheel drive and automatic transmission to rocket it off the line. The Tesla's initial acceleration feels minutely tardy on the first push of the accelerator, the much vaunted maximum torque at zero revs not materialising in quite the manner you'd expect. After the very slight delay though the force it delivers is quite staggering, the effect heightened by the lack of noise. Unlike most conventional cars, acceleration in the Tesla keeps piling on force; it's likely you'll run out of road and nerve before you get anywhere near its 130mph top speed.

Unsurprisingly the Bentley feels the more conventional of the duo, albeit mightily quick. It combines the usual Continental GT traits of long-legged comfort and serenity with the performance dialled up to eleven. With its tuned suspension and the rear-biased four-wheel drive system the Supersports does add agility and greater balance to the Continental over it its relatives, but it still feels heavy. The steering lacks feel, Bentley adding heft to the wheel without any corresponding increase in communication.

By contrast the Tesla feels light and precise. The steering is heavy at town speeds, but get moving and its Lotus roots are apparent with plentiful feel through the small wheel's rim. The suspension does its best to cope with the cracked, undulating tarmac that passes for roads in the UK, but it's not unusual to find yourself wincing in anticipation of manhole covers and poorly-filled potholes.

It is a sports car though and the compromises are worth it for the performance it brings. It's impossible not to enjoy the seemingly limitless thrust from the 244bhp electric motor and the purity of its drivetrain. Its traction control works seamlessly too, enabling you to be brutal with the accelerator even on wet cobbles without fear. It's hilariously fast, though the best bit about driving it is the simple fact that the lentil-eating green dreamers have to accept it simply because it's plug-in and produces no emissions of its own.

Worth Noting

Both these cars are headlined as green machines. The Tesla understandably thanks to its battery propulsion, the Bentley thanks to E85 bio-ethanol capability. What Tesla has achieved is nothing short of incredible, the small company throwing out all the conventions on performance and range for electric cars and setting an extremely high bar for the as yet to be revealed competition to match. It'll do over 200 miles on a full charge depending on how it's driven. Pleasingly charge was still near full after plenty of miles of extremely uneconomical driving in our hands - and it can be charged in as little as 3.5 hours. Is it green though? That depends entirely upon where you buy your electricity, but plug it into the mains and all you're doing is off-loading the carbon output further up the supply chain.

The Bentley is entirely familiar in its powertrain. There's a mighty big engine up front that runs on conventional petrol. However, it's a 'flexfuel' engine, which means if you can find an outlet you can fill the Bentley's tanks with E85 bio-fuel. E85 is an ethanol mix that's created by using crops, which through some convoluted calculations allows you to claim less CO₂ output overall - as the actual growing of the fuel itself off-sets emissions at the tailpipe.

However you look at this pair of cars, the environmental arguments for both can have huge holes shot in them, but that's not to take away from either manufacturer's achievements.

Summary

Whatever you pour into the Bentley's fuel tank you'll get through it at an alarming rate, the big W12 turbocharged engine chewing through fuel to provide its brilliant performance. Seventeen point three mpg is the official combined consumption figure with unleaded; though figure on an average some 5mpg less in reality. Fill it with E85 and you'll get even worse figures, though you can claim a 70 percent reduction in the 388g/km CO₂ by virtue of some novel plant-derived CO₂ soaking mathematics.

The Tesla's green credentials are more clear-cut, in fact it couldn't be more ahead of the curve. Plug it in and go; the electric Tesla removes fossil fuels from the equation - so long as you don't look too deeply. Regardless, both demonstrate that the green doomsayers need not mean the demise of enjoyable performance motoring. And that's good enough for us.