Reg Rumney reports on the potential of the electric vehicle
MENTION “electric car”to your average motorist and you will be greeted with scepticism. They are probably thinking of the homely, battery-powered vans that once used to deliver milk to the sleepy suburbs. Or the ill-fated three-wheeler that made inventor Sir Clive Sinclair a laughing stock.
The converted Honda Civic imported by Eskom as a prototype vehicle could not be more
With a fairly powerful 100kW motor, it looks, feels, and drives like a normal petrol-powered car. However, you can’t help but notice the substantial tunnel running down the middle of the vehicle. This contains the 28 12V lead- acid batteries that provide the DC electricity that converted to AC power, drives the quiet electric motor.
Quiet — but not silent. As it accelerates smoothly towards its top speed of 136km an hour the car emits a high-pitched whine reminiscent of a Datsun Pulsar. The car accelerates from 0 to 100km/h in under nine seconds and the acceleration, unlike in a petrol car, is achieved without gear change.
“It is almost linear,”says Eskom’s Dave Kombol of the car’s acceleration, as he shows what the car can do with a full passenger load of four people. Kombol reckons it has more torque (ability to accelerate) than its petrol-driven equivalent
So the car is not under-powered, as one would expect. If a second gear were used top speed could be increased to over 200km an hour — and the car’s range would be much lower.
The range is only around 120km before recharging, and that is using “regeneration”, in other words using the inertial (momentum) force of the car to recharge the batteries. When the regeneration switch is on, the car slows as the driver takes his foot off the acceleration pedal, just as if he had changed to a lower gear. Otherwise the car coasts to a stop under the force of gravity.
Without regeneration the range is halved. How far you can go on a single recharging of the batteries, which normally takes around six hours a time, also depends on how you drive. High-speed, aggressive driving decreases
Applications in South Africa, where long distances are commonplace are limited, though electric vehicles (EVs) are being considered, for instance, for taxis at the Durban
On the other hand, according to Carel Snyman, who heads Eskom’s electric vehicle programme, South African motor manufacturers, with their relatively short production runs, are ideally placed to take the lead in electric car
Cost is another problem, until mass production brings economies of scale.
The Eskom prototype, imported from Canada, costs R200 000.
Against this running costs are miserly, around 2,5c to four cents/km. It costs between five rand and six rand to recharge the car. So if a tank of petrol costs R95, the equivalent cost for recharging the converted Civic would be around R24, almost a fourth of a petrol- powered equivalent. Also, the batteries and the motor should outlast a petrol engine with careful driving.
So the electric car scores on money and doesn’t do badly on power. What’s the catch?
EVs, as they are known in the US, were more numerous than vehicles driven by the internal combustion engine in the early days of
What put paid to them was the efficiency of petrol in storing energy, and refinements of the internal combustion engine to make it less polluting and more efficient.
EVs were little more than drawing board dreams until pollution concerns in the US and Europe led to environmental demands for the reduction of damaging exhaust emissions.
In any case, the move towards mass production of affordable electric vehicles has been given impetus by California’s tough pollution
The California Air Resources Board has decided that beginning in 1998 two percent of all vehicles sold in California will have to have zero emission of noxious gases. That means that around 25 000 vehicles sold in 1998 will have to be electric vehicles.
Traditional automobile manufacturers have introduced a range of prototypes. Also, Calstart, which describes itself as an advanced transport consortium, has recently unveiled a purpose-built, personal electric car designed to cost under $10 000, or the equivalent of R36 000 or so. The two-passenger commuter car conforms, says Calstart, to US safety standards and has a range of 96 to 128 km. The thermoplastic body may put some South African motorists off, but the Norwegian car is designed to be a second vehicle for nipping around town.
At the same time, The Guardian reports that EVs in French cities already number several thousand and are expected, thanks to a new government subsidy, to reach 100 000 in five years’ time.
French car manufacturers are at the forefront of electric car production, with Renault being the first to construct battery-driven vehicles on the same production lines as its other
While electric cars are no longer museum pieces or sci-fi fantasies, the problems of energy storage still remain, putting the EV tantalisingly out of reach of the ordinary driver. But hopes are now pinned on the development of a range of new batteries, such as the Zebra battery, an Anglo American initiative, or zinc-air batteries, which are not recharged but replenished by putting in fresh anodes.
When these are a commercial reality, the last hurdle will have fallen.
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