ERIC DYMOCK on an Audi hybrid that successfully combines electric and conventional engine power.
GENERAL MOTORS claims to have designed an electric car that can keep up with urban traffic, and last week Audi revealed a hybrid, which does shopping trips on electricity but uses a conventional engine on the motorway. Yet electricity remains a means of transmitting power, not a source of power, and the electric car has not come far since 1899, when Frenchman Camille Jenatzy set the record for the flying kilometre with one at 65.79 mph.
It had to have its batteries charged before it could do the return kilometre, and 90 years of development has not seen much progress in terms of speed, range, or the weight and space needed to carry electricity to run a car. Even with modern sodium-sulphur or nickel-cadmium technology, a four-ton battery the size of a 550 gallon petrol tank would be needed to provide a 500 mile range and 100 mph performance.
California first identified cars as the cause of the photo-chemical smog of Los Angeles in the 1950s, and passed clean-air legislation that has since been adopted around the world. Car manufacturers had to develop exhaust emission control equipment to meet the demand, and now California is taking an initiative aimed at phasing out petrol engines altogether.
The state’s latest call, for 1.7m electric cars by the year 2000 and seven cars in 10 to be electrically powered by 2010, may be the best hope for the development of a relatively pollution-free vehicle with something better than the performance of the average milk-float.
The expectation is that history will repeat itself and, faced with the prospect of not selling cars in California, an inventive industry may come up with something. It seems more likely at this stage that manufacturers will look for markets elsewhere, having decided that electric cars and buses are a modern alchemist’s dream which no amount of money is going to
realise.
Still, mindful of the need to be seen to be doing something, Roger Smith, chairman of General Motors, talks of the Impact, which reaches 60 mph as quickly as a Jaguar XJ6, and has a top speed of 100 mph. It has a range of 124 miles, but what Smith did not say was what speed it was travelling at when it achieved that range, nor how often it had to be recharged after sprinting to 100 mph.
As Jenatzy and generations of milkmen have discovered, electric vehicles can go a long way slowly, or a short way quickly, but not both.
Audi’s answer may not meet all of California’s requirements, but it is more likely to succeed than Smith’s. Closing off town centres to noisy, smelly petrol or diesel vehicles would be a reasonable way of making streets habitable again. The Audi hybrid represents a practical response, which could go on sale almost at once.
The company took an Avant quattro, the four-wheel drive estate car, and installed an electric motor to drive the rear wheels, leaving the combustion engine (petrol or diesel) to drive the front ones. The advantage is that drive to the rear wheels is already in place, and the electric motor can be installed neatly in the transmission tunnel driving the back wheels through an electrically-operated clutch.
The nickel-cadmium batteries go into the space normally occupied by the spare wheel and last up to ten years. They provide sufficient power to drive the car at 30 mph and accelerate to 20 mph in eight seconds - perfectly adequate for town driving, operating range at town speeds is about 20 miles.
On the motorway, the combustion engine takes 45 minutes to recharge the batteries. The extra weight of the installation (60 kg for the motor 181 kg for the batteries) is catered for by uprated springs and dampers, and tyres of the sort Audi offers for load-carrying estate cars.
Changing from one drive to the other is accomplished by the turn of a switch. A small extra electric motor is required to drive the hydraulic systems, power steering the like, and there is a petrol-fed water heater. Audi expects the extra cost to be around Dm 25,000 (£9,260).
Audi is seeking reaction from local authorities, delivery services and residents in noise and pollution-controlled streets before deciding its next step. 2015 Concept (below)
