| Customary electro-technology |
The drive ia an asynchronous three-phase motor with a max. torque of 190 nm and 66 kW performance. The 'tank', a 280 kg lithium-ion battery, allows a range of 150-200 kms, but only if you're not in a big hurry.
Compared to the same vehicle with a combustion engine, the acceleration and performance are somewhat lower. They would be even lower, if the roof and bonnet were not especially light-weight, and the rear axle
and brakes were not made of aluminium. Thus, it is only approx. 100 kg heavier. It does not have a gearbox. The electric power-steering and the
electric heating form a
|Fast and furious prototype|
At the moment (2008), the most realistic project comes from the Tesla Motor Company in California. The sports car has a top speed of 200km/h and can reach 100 km/h in just under 4 seconds. The operational range
is stated at 360 km, which, in this sports car is definitely not possible. Then, unfortunately, it must be hooked up to a charging point for 16 hours.
|More than 350 kms at a constant 100 km/h|
By far the most expensive components in the car are the, almost 7.000 lithium-ion-accumulators, they are the same size as those sold in the shops and according to the manufacturers, after about 160.000 kms they
must be replaced, for one tenth of the purchasing price of €150.000. If we assume a total of 56 kW, that makes, at 3,7 V, a still substantial 2,2 A per accumulator. The vehicle is developed and produced by Lotus,
which promises a particularly lightweight construction. If we assume a consumption of approx. 15 kW per 100 kms, then even the operational range of 350 kms can be explained.
|Named after a genius, with a lot of engine power |
The company and the car are named after Nikola Tesla who initially studied with Edison and later, became his most prominent adversary. He was, among other things, an advocate for alternating current (AC), which in
turn, applies to the car, which has just such an asynchronous motor with 185 kW (248 HP), making the claimed performance plausible.
|Is an electro-vehicle possibly still reasonable?|
The momentary exchange rate of the US-Dollar would help the Tesla Roadster to achieve, at least, the same desirability status in Europe. The price being asked is $92.000 - $98.000, which means, just below or just
above €70.000. One can expect even higher savings with the running costs. In the USA, $0.02 per kilometer is estimated. If only the batteries hold out. Here, one is assuming 500 charging cycles, which would
correspond to 160.000 kms. Of course, only under the premise, that one does not use the available performance all the time.
|Lithium-ion batteries are critical during charging|
When charging, no malfunctions may occur, since lithium-ion accumulators are critical about (dis-)charging. Will they be able to cope with a relatively quick charging in approx. 3,5 hours? They are also inflammable,
this is avoided in the roadster, through a cooling circuit and by pooling them into units of approx, 100. One can suspect that the operational range will not be achieved, because the batteries can't be fully charged or
fully run down. Therefore, there is also the guarantee that, after 160.000 kms, they will still take on, at least, 80% of the charge.
|Can an electro-vehicle be environmentally friendly nowadays? |
No, because obviously there is not sufficient renewable energy available for motoring. Using customary energy to charge the battery, the balance in electric cars is no better than that in cars with combustion engines.
Indeed, one can, and one must do the developing now, to be ready for the time when sufficient renewable energy is there. Apart from that, the huge toll fees in big city-centers (e.g. London) will not apply to these
|The electric drive is an integral part of the near future.|
Nowadays, one can already say, that cars with additional-, or solely with electric motors, will probably be the vehicles for the masses in the near future. This particularly, because the development of the hydrgen market
with it's gigantic infrastructure costs, is not yet foreseeable. Also the method of storage can not be predicted. There are already inventions, where the energy can be trasferred to the vehicle by induction, through cables
under the road surface. Indeed, the storage in the car is more probable. The recharging takes place during the night through a computer, according to the most favourable rate. Especially intelligent systems can then
gamble and resell parts of the charge during alternating tarifs. The stock exchange in the outlet-plug, indeed not really beneficial for the battery.
|Competition for the lithium-ion battery|
It is becoming clear, that for cars which run exclusively on self-generated current, there will be battery types that differ from those used in cars which recharge from an outlet (plug-in). In this case, Toyota recommends
lithium-ion batteries for purely electrc cars, and nickle-metal-hydride for full-hybrid cars with the plug-in possibility. The latter have had many years of practical testing, with uncountable charge-discharge processes
and have been improved accordingly. One point is however, valid for both types: Fast and powerful cars with batteries, will not have a large operational range, this can only be achieved in lighter, compact cars.
|Single-axle city-vehicle with a top speed of 60 km/h|
Electric 'stand-up'-scooters have been around for some time now. However, that they are being offered as an accessory in (electric) cars is something new. The inner-city tax is taking it's toll. In this category, is the
glass-roofed, single-axle vehicle, which functions like a 'Segway' and will probably be approved (also) for use on the roads. It is however, designed for two seated people and will be, the same as it's role-model,
controlled by the shifting of weight. Let's hope that the coordination functions. At the moment, the elegant appearance is somewhat damped by supporting wheels at the front and rear. 09/09