Sean O'Grady: Just the beginning of the car's evolution

The name Leaf puts me in mind of a famous quotation of Chairman Mao's: "Let a thousand flowers bloom." This, it is fair to say, is what is happening in the motoring world now. Alternative – and practical – technologies are blossoming, and they are mostly greener than we have ever seen before.

As the Leaf shows, the electric vehicle has come a long way form the milk float; it joins the existing petrol-electric hybrid cars like the Toyota Prius in adding to the choice offered to the driver. There are others too, albeit less successful or further away from the market. Honda, GM and Mercedes have all developed hydrogen fuel cell cars.

Toyota will soon bring us their plug-in Prius, which supplements its onboard charging with electricity from the mains. Saab has led the way in bio-fuels; BMW in using hydrogen as a substitute fuel for petrol. And of course the internal combustion engine just keeps being developed to be green and more efficient. Emissions of the average car are a fraction of what they were a couple of decades ago.

Cars, in other words, have never been greener. And like in the early days of the car, these new technologies will fight it out for supremacy. In the 1890s many thought that the electric car would win out before Karl Benz's idea triumphed; steam power was a viable option. Electric cars might be the choice for city and suburban driving and delivery vans; super-efficient diesels for family cars, SUVs and lorries; hybrids for executive saloons and MPVs; good old petrol for performance machines. One day a single technology may win out as the petrol engine did; meanwhile we should wonder at the evolution of the species.