Electric Ka

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here are a number of specialist engineering companies who, for a princely sum of money, can convert most road going cars to be electrically driven. This involves ripping out the engine and transmission and replacing them with an electric motor and associated ancillary systems, and of course one or more battery packs.

Performance

Although the concept of an electric powered vehicle may conjure up the image of a milk float doddering along at 20 mph, this isn’t what these conversions are about. Most of them offer comparable acceleration up to the national speed limit, or at the very least up to around 40 mph.

Electric motors offer instantaneous torque, so (subject to the transmission) there is usually quite a bit of acceleration available.

Range

Electric vehicles cannot really have a definition of fuel consumption aside from range or endurance. The range of an electric converted vehicle depends on the capacity of the batteries - and this depends on their size and type. Lead acid batteries are the cheapest, and typically the heaviest, whereas Lithium Ion batteries are less dense and can therefore carry significantly more power for a given mass.

Unfortunately, the range of most of these vehicles is under one hundred miles (under optimum conditions) - this means at a modest cruise with no time spent in stop / go traffic. Although our commute to and from work will be forty miles each way, so in theory we’d be able to go to and from work on a single charge, I would really need the means of topping the battery up whilst we’re at the office because in winter, when we need headlights, we may not make it home. This is not to mention any trips somewhat further then work.

Other Compromises

In addition the compromises discussed above, there are some other complications associated with the operation. One, the batteries need to be stored somewhere in the car. This either means under the bonnet, or in the boot. Neither space is especially large - some companies prefer to put batteries elsewhere since this spreads the weight of the electrical system.

As far as weight goes, high capacity batteries are rather heavy and this adds to the car. Some systems weigh around 200 kg, which is course is to the detriment of range and performance.

Unfortunately, none of the electric conversions currently offer air conditioning.

One other compromise involves the amount of cooling that these systems require. Electric motors can get very hot in operation!

Conclusion

I love the idea of an electric vehicle for commuting purposes, however the technology is either too compromised, or too expensive, at this juncture.

One compromise is in the form of the hybrid vehicle, that is, a car that has both an internal combustion engine and electric motors.