Are electric cars any more energy efficient than conventional ones?

Asked by: John Awbery, Reading

About 90 per cent of the power that goes into an electric motor is converted into torque to turn the car's wheels. In a petrol car, the efficiency is only about 25 per cent. And, unlike electric cars, petrol motors continue using up energy even when idling.

However, when you take into account energy costs in generating the power used to charge an electric vehicle's batteries, the efficiency is pretty much the same as in petrol cars.

Read more:

• How environmentally friendly are electric cars?
• If every petrol or diesel car in the UK was replaced with an electric car, how many charging points would we need?

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