Think of the resounding roar from the rear of a Corvette.
eight precise cylinders, the power of the rhythmic piston rods and cranks of the drive shaft, destined to last for decades.
Eight Poly-V belt pulleys rotating thanks to a single camshaft turned and bored with maniacal precision. Two valves per cylinder, super-sensitive and non-deformable springs. That’s the internal combustion engine. An engine which guarantees a performance of around 300% after a thorough running-in. To explain it simply, €65 of the €100 of petrol you put in your splendid, high-performing, beguiling Corvette goes on heat, tyre wear and noise. Now think of the twittering of a goldfinch. A mellow sound which causes no disturbance even in moments of maximum concentration. Tremulous, relaxing notes.
That’s the electrical engine of the Tesla Roadster.
An engine which has an over-90% performance, not comparable in efficiency to a combustion engine. And it’s no longer just a question of horsepower. All car manufacturers, especially since the advent of the supercharged diesel, now advertise their “couple” values (nothing to do with interpersonal relationships).
The couple of a car is a function of the engine rpm and is simply the speed at which the engine reaches full capacity, hence a measure of the efficiency of everything making up the driving system. Driving fluidity is a consequence of this. And the fluidity of the Tesla Roadster is at the highest levels achieved in the sector. All well and good, we have an efficient engine, but is it also effective? After all I’m buying a two-seater roadster, not the runabout my wife uses to do the shopping. I would like it that when I press down on the accelerator my seat implores me to slow down a little because I’m suffocating it at 2½ g. Does this happen? Incredible. It happens. We have a car with 90% performance and a zero to one hundred acceleration of 3.7 seconds. We are going way above 2½ g, which means that once belts are fastened we can expect thrills. Just so as you understand, we are
three-tenths of a second above the Pagani Zonda C12. Not bad at all. So we not only have a car with exceptional performance and an attractive shape, the carbon bodywork was created in collaboration with Lotus Cars, but this has an utterly deadly acceleration.
It’s electric, though, it works by battery and needs recharging.
But how often? This depends a lot on the use we want to make of the car. The on-board computer allows us to choose from 3 operational modes (Performance, Maximum Range, Standard) and it governs the lithium ion battery recharging system also included in the deal. If you choose the Maximum Range mode you can travel for over 390 km. The battery is charged on the special columns in about 3½ hours, while if it is charged using the home electricity system it takes between 10 and 15 hours. Now we might think these are rather long times. But just think of your cell phone, of how long it takes to recharge, and you’ll understand that leaving the car to recharge for 10 hours overnight is not really so long if we compare it with the number of Km we can then do on it. The long life of the battery is to be attributed not only to its advanced technology, but also to the type of brakes the car has. These are in fact regenerative brakes, with a generator attached to the wheel axes which recovers the heat developed in braking and converts it into kinetic energy, a system wholly similar to the Kinetic Energy Recovery System (K.E.R.S.) of Formula One cars. It is probably thanks to this highly productive technology that the Tesla Roadster won first the Rallye Monte Carlo d’Energies Alternatives, setting up a new world record, only to break it a few months later at the Global Green Challenge in Australia, resetting it at 501 Km with a single recharge. If you are interested, for information and bookings you can directly access the site www.teslaroadster.com, where you can also listen to the comments of some enthusiastic users. I clicked on “buy” straightaway, more out of curiosity than anything, and I got a pleasant surprise. Any flaws? Well, the goldfinch is not included.