ONE develops 76bhp and achieves 65.7mpg, the other puts out more than 900bhp at less than 4mpg, but they are both Toyotas and both are associated with Panasonic.

Not only does it have its name on the Toyota F1 car, but now the electronics giant also uses the eco-friendly Prius on its 300-strong fleet.

The firm has taken delivery of two of the cars and another is on order.

The F1 car packs a 3.0-litre V10 petrol engine and reaches peak power at 19,000rpm.

Its smaller brother has a 1.5-litre petrol engine under the bonnet, helped by an electric motor at low speeds, and runs out of puff at 5,000rpm. But it is a lot less nasty to the environment, producing a lowly 104g/km of CO2.

Panasonic’s fleet manager Sue Fuhr said: ‘Obviously it’s good to have an environmentally friendly car, and the congestion charge exemption is a bonus.

‘We were impressed with its performance and think its quietness will be good for drivers’ well-being, particularly in London.’